IEC 60335 -1 
Edition  6.0 2020 -09 
INTERNATIONAL  
STANDARD  
Household and similar electrical appliances – Safety – 
Part 1: General requirements  
IEC 60335 -1:2020 -09(en) 
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 IEC 60335 -1 
Edition  6.0 2020 -09 
INTERNATIONAL  
STANDARD  
 
Household and similar electrical appliances – Safety –  
Part 1: General requirements  
 
 
  
INTERNATIONAL  
ELECTROTECHNICAL  
COMMISSION 
  
ICS 13.120; 97.030   
ISBN 978-2-8322 -8600 -5 
   
  
® Registered trademark of the International Electrotechnical Commission  
® 
 
   Warning! Make sure that you obtained this publication from an authorized distributor.  
 
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 IEC 60335 -1:2020/ISH 1:2021 – 1 –  
© IEC 20 21 
 ICS 13.120; 97.030   INTERNATIONAL ELECTROTECHNICAL COMMISSION  
____________  
 
IEC 60335-1 
Edition 6.0   2020-09 
 
 
HOUSEHOLD AND SIMILAR ELECTRICAL APPLIANCES – SAFETY –  
 
Part 1: General requirements  
  
INTERPRETATION SHEET  1  
  
This interpretation sheet has been prepared by IEC technical committee 61: Safety of 
household and similar electrical appliances.  
The text of this I nterpretation Sheet is based on the following documents:  
Draft  Report on voting  
61/5999/D ISH 61/6009/ RVDISH 
 
Full information on the voting for its  approval can be found in the report on voting indicated in 
the above table.  
 
___________ 
 
INTRODUCTION  
Edition 6 of IEC  60335- 1:2020 defines  and introduces  requirements  for a detachable 
power  supply  part of an appliance.  In the document , 24.2 prohibits  the use of a power  
supply  in a flexible  cord.  
QUESTION:  
Does  Subclause 24.2 prohibit  the use of a detachable  power  supply  part? 
ANSWER  
No, a "detachable power  supply  part" is a defined  term and is not captured  by the term 
"power  supply " as used in Subclause 24.2.  
NOTE  A detachable power  supply  part is captured by the defined term  when  the output  of the power  supply  
part is detachable from  the class III construction part of the appliance at: 
– the power  supply  part,  or 
– the class III construction part of the appliance.  
However,  the supply  cord (if  any)  does  not  have to be detachable from  the detachable power  supply  part.  IEC 6 0335 -1:2020-09/ISH1:2021-11(en)   – 2 – IEC 60335- 1:2020 ©  IEC 20 20        CONTENTS 
FOREWORD .........................................................................................................................  6 
INTRODUCTION ...................................................................................................................  9 
 
1 Scope .......................................................................................................................... 11 
2 Normative references  .................................................................................................. 11 
3 Terms and definitions .................................................................................................. 16 
4 General requirement  ....................................................................................................  28 
5 General conditions for the tests ....................................................................................  28 
6 Classification  ...............................................................................................................  32 
7 Marking and instructions ..............................................................................................  32 
8 Protection against access to live parts .........................................................................  41 
9 Starting of motor -operated appliances  .......................................................................... 43 
10 Power input and current  ...............................................................................................  43 
11 Heating  .......................................................................................................................  45 
12 Charging of metal -ion batter ies ....................................................................................  51 
13 Leakage current and electric strength at operating temperature  ....................................  52 
14 Transient overvoltages  ................................................................................................ 55 
15 Moist ure resistance ..................................................................................................... 55 
16 Leakage current and electric strength ...........................................................................  58 
17 Overload protection of transformers and associated circuits.......................................... 60 
18 Endurance ...................................................................................................................  60 
19 Abnormal operation ..................................................................................................... 60 
20 Stability and mechanical hazards .................................................................................  71 
21 Mechanical strength  ..................................................................................................... 72 
22 Construction ................................................................................................................  74 
23 Internal wiring  ..............................................................................................................  86 
24 Components  ................................................................................................................  88 
25 Supply connection and external flexible cords ..............................................................  93 
26 Terminals for external conductors ..............................................................................  101 
27 Provision for earthing ................................................................................................. 103 
28 Screws and connections  ............................................................................................  105 
29 Clearances, creepage distances and solid insulation .................................................. 107 
30 Resistance to heat and fire ........................................................................................ 116 
31 Resistance to rusting ................................................................................................. 121 
32 Radia tion, toxicity and similar hazards ....................................................................... 121 
 
Annex  A (informative)  Routine tests  .................................................................................. 135 
Annex  B (normative)  Battery -operated appliances, separable batteries and detachable 
batteries for battery -operated appliances  ...........................................................................  137 
Annex  C (normative)  Ageing test on motors  ....................................................................... 158 
Annex  D (normative)  Thermal motor protectors  .................................................................. 159 
Annex  E (normative)  Needle- flame test  ............................................................................. 160 IEC 60335- 1:2020 © IEC 2020 – 3 –         Annex  F (normative)  Capacitors  ........................................................................................ 161 
Annex  G (normative)  Safety isolating transformers  ............................................................  163 
Annex  H (normative)  Switches  ..........................................................................................  164 
Annex I (normative)  Motors having basic insulation that is inadequate for the rated 
voltage of the appliance ....................................................................................................  166 
Annex  J (normative)  Coated printed circuit boards  ............................................................. 168 
Annex  K (informative)  Overvoltage categories  ...................................................................  169 
Annex  L (informative) Guidance for the measurement of clearances and creepage 
distances  ..........................................................................................................................  170 
Annex  M (informative) Pollution degree  ............................................................................. 173 
Annex  N (normative)  Proof tracking test  ............................................................................  174 
Annex  O (informative)  Selection and sequence of the tests of Clause 30 ............................  175 
Annex  P (informative)  Guidance for the application of this standard to appliances  used 
in tropical climates  ............................................................................................................  180 
Annex  Q (informative)  Sequence of tests for the evaluation of electronic circuits  ................  182 
Annex  R (normative)  Software evaluation  .......................................................................... 185 
Annex  S (informative)  Guidance for the application of this standard on measurement of 
power input and current based on the requirements of 10.1 and 10.2 concerning the 
representative period ........................................................................................................  199 
Annex  T (normative)  UV-C radiation effect on non -metallic materials  ................................. 200 
Annex  U (normative)  Appliances intended for remote communication through public  
networks  ...........................................................................................................................  203 
Bibliography  ..................................................................................................................... 207 
Index of defined terms  ......................................................................................................  210 
 
Figure 1 – Circuit diagram for leakage current measurement at operating temperature 
for single -phase connection of class II appl iances  and for parts of class ll construction ...... 122 
Figure 2 – Circuit diagram for leakage current measurement at operating temperatur e 
for single -phase connection of other than class II appliances  or parts of class ll 
construction ......................................................................................................................  123 
Figure 3 – Circuit diagram for  leakage current measurement at operating temperature 
for three- phase with neutral class II appliances and for parts of class ll construction .......... 124 
Figure 4 – Circuit diagram for leakage current measurement at operating temperature 
for three- phase with neutral appliances other than those of class II or parts of class ll 
construction ......................................................................................................................  125 
Figure 5 – Small part  ........................................................................................................  126 
Figure 6 – Example  of an electronic circuit with low -power points  ....................................... 126 
Figure 7 – Test finger nail  ................................................................................................. 127 
Figure 8 – Flexing test apparatus  ......................................................................................  128 
Figure 9 – Constructions of cord anchorages  ..................................................................... 129 
Figure 10 – An example of parts of an earthing termina l ....................................................  130 
Figure 11 – Examples of clearances  .................................................................................. 131 
Figure 12 – Example of the placement of the cylinder  ........................................................ 132 
Figure 13 – Small parts cylinder ........................................................................................ 133 
Figure 14 – Example of a specified operating region of a lithium -ion cell during charging  .... 134 
Figure B.1 – Examples of battery -operated appliance constructions and application of 
normative Annex  B ...........................................................................................................  155  – 4 – IEC 60335- 1:2020 ©  IEC 20 20        Figure B.2 – Examples of correct polarity connection marking representing three 
batteries  ...........................................................................................................................  157 
Figure I.1 – Simulation of faults  .........................................................................................  167 
Figure L.1 – Sequence for the determination of clearances ................................................  170 
Figure L.2 – Sequence for the determination of creepage distances  ...................................  171 
Figure L.3 – Measurement of clearances ...........................................................................  172 
Figure O.1 – Tests for resistance to heat  ...........................................................................  175 
Figure O.2 – Selection and sequence of tests for resistance to fire in hand -held 
appliances  ........................................................................................................................ 176 
Figure O.3 – Selection and sequence of tests for resistance to fire in attended 
appliances  ........................................................................................................................ 176 
Figure O.4 – Selection and sequence of tests for resistance to fire in unattended 
appliances  ........................................................................................................................ 177 
Figure O.5 – Some applications of the term "within a distance of  3 mm" ............................. 179 
Figure Q.1 – Flowchart outlining the sequence of tests for the evaluation of electronic 
circuits  ............................................................................................................................. 183 
Figure S.1 – Flowchart giving guidance on measurement of power input and current 
concerning the representative period  .................................................................................  199 
 
Table 1 – Power input deviation ..........................................................................................  43 
Table 2 – Current deviation ................................................................................................. 44 
Table 3 – Maximum normal temperature rises ..................................................................... 47 
Table 4 – Voltage for electric strength test  .......................................................................... 54 
Table 5 – Characteristics of high- voltage sources  ................................................................ 54 
Table 6 – Impulse test voltage ............................................................................................  55 
Table 7 – Test voltages  ....................................................................................................... 59 
Table 8 – Maximum winding temperature ............................................................................. 63 
Table 9 – Maximum abnormal temperature rise ...................................................................  69 
Table 10 – Dimensions of cables and conduits ....................................................................  94 
Table 11 – Minimum cross -sectional area of conductors  ......................................................  96 
Table 12 – Pull force and torque .........................................................................................  98 
Table 13 – Nominal cross -sectional area of conductors ......................................................  102 
Table 14 – Torque for testing screws and nuts  ...................................................................  106 
Table 15 – Rated impulse voltage ..................................................................................... 108 
Table 16 – Minimum clearances  ........................................................................................ 109 
Table 17 – Minimum creepage distances for basic insulation ............................................. 113 
Table 18 – Minimum creepage distances for functional insulation ....................................... 114 
Table 19 – Minimum thickness for accessible parts of reinforced insulation consisting 
of a single layer  ................................................................................................................  116 
Table A.1 – Test voltages  ................................................................................................. 136 
Table B.1 – Artificial source characteristics  ....................................................................... 139 
Table B.2 – Total area of openings for metal -ion cells  ........................................................ 147 
Table B.3 – Volume of air injected at 2 070 kPa  ................................................................. 147 
Table C.1 – Test conditions  ...............................................................................................  158 
Table R.1 – General fault/error conditions .........................................................................  187 IEC 60335- 1:2020 © IEC 2020 – 5 –         Table R.2 – Specific fault/error conditions  .........................................................................  189 
Table R.3 – Semi -formal methods  ..................................................................................... 195 
Table R. 4 – Software architecture specification ................................................................. 195 
Table R. 5 – Module design specification ............................................................................  196 
Table R. 6 – Design and coding standards  .........................................................................  197 
Table R. 7 – Software safety validation  ..............................................................................  197 
Table T.1 – Minimum property retention limits after UV -C exposure ...................................  201 
Table T.2 – Minimum electric strength for internal wiring after UV -C exposure ....................  202 
Table U.1 – Examples of acceptable measures against unauthorised access and 
transmission fault/error modes ..........................................................................................  205 
 
   – 6 – IEC 60335- 1:2020 ©  IEC 20 20        INTERNATIONAL ELECTROTECHNICAL COMMISSION  
____________ 
 
HOUSEHOLD AND SIMILAR ELECTRICAL APPLIANCES –  
SAFETY –  
 
Part 1: General requirements  
 
FOREWORD 
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising 
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote international 
co-operation on all questions c oncerning standardization in the electrical and electronic fields. To this end and 
in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports, 
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preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with 
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with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for 
Standardization (ISO) in accordance with conditions determined by agreement between the two organizations.  
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international 
consensus of opinion on the relevant subjects since each technical committee has representation from all 
interested IEC National Committees.  
3) IEC Publ ications have the form of recommendations for international use and are accepted by IEC National 
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC 
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any 
misinterpretation by any end user.  
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications 
transparently to the maximum extent possible in their national and regional publications. Any divergence between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter.  
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity 
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any 
services carried out by independent certification bodies.  
6) All users should ensure that they have the latest edition of this publication.  
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and 
members of its technical committees and IEC National Committees for any personal injury, property damage or other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and 
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC Publications.  
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is indispensable for the correct application of this publication.  
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of patent rights. IEC shall not be held responsible for identifying any or all such patent rights.  
International Standard IEC 60335- 1 has been prepared by IEC technical committee  61: Safety 
of household and similar electrical appliances.  
This sixth edition cancels and replaces the fifth edition published in 2010, Amendment 1:2013 
and Amendment 2 :2016. This edition constitutes a technical revision.  
This edition includes the following significant technical changes with respect to the previous 
edition (minor ch anges are not listed ): 
a) updated the text of this standard  to align with the most recent editions of the dated normative 
references;  
b) deleted some notes and converted many other notes , in whole or in part, to normative text;  
c) changed some Annex designations from normative to informative;  
d) introduced information on Guidance documents concerning the application of the safety 
requirements covered by IEC 60335 series and on how to retrieve them ; 
  IEC 60335- 1:2020 © IEC 2020 – 7 –         e) clarified requirements for PELV circuits;  
f) clarificatio n of requirements on measurement of power input and rated current when they 
vary throughout the operating cycle;  
g) replaced normative Annex  S with the informative Annex  S "Guidance for the application of 
this standard on measurement of power input and curren t based on the requirements of 10.1 
and 10.2 concerning the representative period"; 
h) introduced and clarified mechanical strength requirements for appliances with integral pins 
for insertion into socket -outlets;  
i) revised requirements for battery -operated appliances;  
j) introduced requirements for metal -ion batteries  including  a new Clause 12  Charging of 
metal -ion batteries;  
k) introduced the application of test probe 18;  
l) introduced requirements for appliances incorporating appliance outlets and socket -outlets 
accessible to the user;  
m) revised and clarified requirements for appliances incorporating a functional earth;  
n) introduced moisture resistance test requirements for appliances that incorporate an automatic cord reel and that have a second numeral IP rating ; 
o) clarified the appliance test criteria for the moisture resistance for appliances and parts of appliances with integral pins for insertion into socket -outlets;  
p) introduced limits on the output voltage of an accessible safety extra -low voltage ou tlet or 
connector or Universal Serial Bus (USB) under abnormal operation conditions;  
q) introduced requirements to cover optical radiation hazards;  
r) introduced external communication software management items into normative Annex  R; 
s) revised external communicat ion requirements in Table R.1 and Table R.2; 
t) introduced in new normative Annex  U cyber security requirements to avoid  unauthorized 
access and the effects of transmission failures via remote communication through public networks . 
The text of this International Standard is based on the following documents:  
FDIS  Report on voting 
61/6012/FDIS  61/6089/RVD  
 Full information on the voting for the approval of this International Standard can be found in the 
report on voting indicated in the above table.  
The language used for the development of this International Standard is English.  
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.  
A list of all parts of the IEC 60335 series, published under the general title Househo ld and 
similar electrical appliances – Safety , can be found on the IEC website.  
This part is to be used in conjunction with the appropriate part 2 of IEC  60335. The parts 2 
contain clauses to supplement or modify the corresponding clauses in this part to p rovide the 
relevant requirements for each type of appliance. 
This sixth edition of IEC 60335- 1 is only to be used in conjunction with parts 2 that have been 
established on the basis of this edition . 
   – 8 – IEC 60335 -1:2020 ©  IEC 20 20        The following print types are used:  
– requirements: in roman type;  
– test specifications: in italic  type;  
– notes: in small roman type.  
Words in  bold  in the text are defined in Clause 3. When a definition concerns an adjective, the 
adjective and the associated noun are also in bold.  
The committee has decided that th e contents of this document will remain unchanged until the 
stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to 
the specific document . At this date, the document will be  
• reconfirmed,  
• withdrawn,  
• replaced by a revised edition, or  
• amended.  
NOTE  The attention of National Committees is drawn to the fact that equipment manufacturers and testing 
organizations may need a transitional period following publication of a new, amended or revised IEC publication in 
which to make products in accordance with the new requirements and to equip themselves for conducting new or revised tests.  
It is the recommendation of the committee that the content of this publication be adopted for implementation nationally 
not earlier than 12 months or later than 36 months from the date of publication.  
The following differences exist in the countries indicated below.  
– Introduction: The Part 1 standard (UL60335 -1) is only used in combination with a part 2 (UL60335-2- x). National 
differences are specified in these standards (USA).  
– 5.7: The ambient temperature is 25 °C ± 10 °C (Japan).  
– 5.7: The ambient temperature is 27 °C ± 5 °C (India).  
– 6.1: Class 0 appliances and class 0I appliances are not allowed (Australia, European Union, India,  Israel, 
New Zealand, Norway, Singapore, Switzerland, United Kingdom).  
– 7.12.2: The requirements for full disconnection do not apply (Japan).  
– 7.12.8: The maximum inlet water pressure shall be at least 1,0 MPa (Denmark, Norway, Sweden and Finland).  
– 13.2: Th e test circuit and some leakage current limits are different (India).  
– 19.5: The test is also applicable to appliances intended to be permanently connected to fixed wiring (Norway).  
– 22.2: The second paragraph of this subclause dealing with single -phase class I appliances with heating elements 
cannot be complied with because of the supply system (France).  
– 22.2: The second paragraph of this subclause, that deals with single- phase, permanently connected class I 
appliances having heating elements, is not applicable due to the supply system (Norway) . 
– 22.2: Double -pole switches or protective devices are required (Norway).  
– 25.3: A set of supply leads is not permitted (Norway, Denmark, Finland, Netherlands).  
– 25.8: 0,5  mm
2 supply cords are not allowed for class I appliances (Australia and New Zealand).  
 
IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates 
that it contains colours which are considered to be useful for the correct understanding 
of its contents. Users should therefore print this document using a colour printer.  
The contents of the Interpretation Sheet 1 (2021- 11) and the corrigendum 1 (2021- 12) have 
been included in this copy.  
 
  IEC 60335- 1:2020 © IEC 2020 – 9 –         INTRODUCTION  
It has been assumed in the drafting of this International Standard that the execution of its 
provisions is entrusted to appropriately qualified and experienced persons.  
Guidance documents concerning the application of the safety requirements for appliances can be accessed via TC 61 supporting documents on the IEC website –  
www.iec.ch/tc61/sup portingdocuments  
This information is given for the convenience of users of this International Standard and does not constitute a replacement for the normative text in this standard . 
This standard recognizes the internationally accepted level of protection against hazards such as electrical, mechanical, thermal, fire and radiation of appliances when operated as in normal 
use taking into account the manufacturer's instructions. It also covers abnormal situations that 
can be expected in practice and takes into account the way in which electromagnetic 
phenomena can affect the safe operation of appliances.  
This standard takes into account the requirements of IEC 60364 as far as possible so that there 
is compatibility with the wiring rules when the appliance is connected to the supply mains. 
However, national wiring rules may differ.  
If the functions of an appliance are covered by different parts 2 of IEC 60335, the relevant part  2 
is applied to each function separately, as far as is reasonable. If applicable, the influence of one function on the other is taken into account.  
Throughout this publication, when "part 2 " is mentioned, it refers to the relevant part of 
IEC 60335.  
When a part 2 standard does not include additional requirements to cover hazards dealt with in 
Part 1, Part 1 applies.  
NOTE  1 This means that the technical committees responsible for the part 2 standards have determined that it is 
not necessary to specify particular requirements for the appliance in question over and above the general 
requir ements.  
This standard is a product family standard dealing with the safety of appliances and takes 
precedence over horizontal and generic standards covering the same subject.  
NOTE  2 Horizontal publications , basic safety  publication s and group safety publi cations covering a hazard are not 
applicable since they have been taken into consideration when developing the general and particular requirements 
for the IEC  60335 series of standards.  
Individual countries may wish to consider the application of this stan dard , as far as is 
reasonable, to appliances not mentioned in a part 2, and to appliances designed on new 
principles.  In this case , consideration should be given to defining normal operation, specifying 
the classification of the appliance according to Clause  6 and specifying whether the appliance 
is operated attended or unattended. Consideration should also be given to particular categories 
of likely users and to related specific risks such as access to live parts, hot surfaces or hazardous moving parts.
 
An appliance that complies with the text of this standard will not necessarily be considered to comply with the safety principles of this standard  if, when examined and tested, it is found to 
have other features which impair the level of safety covered by these requirements.   – 10 – IEC 60335- 1:2020 ©  IEC 20 20        An appliance employing materials or having forms of construction differing from those detailed 
in the requirements of this standard may be examined and tested according to the intent of the 
requirements and, if found to be substantially equivalent, may be considered to comply with this 
standard . 
NOTE 3 Standards dealing with non- safety aspects of household appliances are: 
– IEC standards published by TC 59 concerning methods of measuring performance;  
– CISPR 11, CISPR 14-1 and relevant IEC 61000- 3 series standards  concerning electromagnetic emissions; 
– CISPR 14 -2 concerning electromagnetic immunity;  
– IEC standards published by TC 111 concerning environmental matters . 
 
  IEC 60335- 1:2020 © IEC 2020 – 11 –          HOUSEHOLD AND SIMILAR ELECTRICAL APPLIANCES –  
SAFETY –  
 
Part 1: General requirements  
 
  
1 Scope  
This International Standard deals with the safety of electrical appliances for household and similar purposes, their rated voltage being not more than 250 V for single -phase appliances 
and 480 V for other appliances  including  direct current ( DC) supplied appliances  and battery -
operated appliances . 
Appliances not intended for normal household use but which nevertheless may be a source of danger to the public, such as appliances intended to be used by laymen in shops, i n light 
industry and on farms, are within the scope of this standard.  
This standard deals with the reasonably foreseeable  hazards presented by appliances that are 
encountered by all persons. However, in general, it does not take into account : 
– persons (incl uding children) whose  
• physical, sensory or mental capabilities; or  
• lack of experience and knowledge 
prevents them from using the appliance safely without supervision or instruction;  
– children playing with the appliance.  
Additional requirements may be necessary for appliances intended to be used in vehicles or on 
board ships or aircraft. In many countries, additional requirements are specified by the national 
health authorities, the national authorities responsible for the protection of labour, the national  
water supply authorities and similar authorities.  
This standard does not apply to : 
– appliances intended exclusively for industrial purposes;  
– appliances intended to be used in locations where special conditions prevail, such as the presence of a corrosive or explosive atmosphere (dust, vapour or gas);  
– audio, video and similar electronic apparatus ( IEC 60065);  
– medical electrical equipment (IEC 60601  series ); 
– hand -held motor -operated electric tools ( IEC 60745  series ); 
– information technology equipmen t (IEC 60950- 1); 
– transportable motor -operated electric tools ( IEC 61029  series ); 
– audio/video, information and communication technology equipment ( IEC 62368- 1); 
– electric motor -operated hand -held tools, transportable tools and lawn and garden machinery 
(IEC 62841 series).  
2 Normative references  
The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any 
amendments) applies.   – 12 – IEC 60335- 1:2020 ©  IEC 20 20        IEC 60034 -1, Rotating electrical machines – Part 1: Rating and performance 
IEC 60061 -1, Lamp caps and holders together with gauges for the control of interchangea bility 
and safety – Part 1: Lamp caps  
IEC 60065:2014, Audio, video and similar electronic apparatus – Safety requirements  
IEC 60068 -2-2, Environmental testing – Part 2 -2: Tests – Test B: Dry heat  
IEC 60068 -2-31, Environmental testing – Part 2 -31: Tests – Test Ec: Rough handling shocks, 
primarily for equipment -type specimens  
IEC 60068 -2-75, Environmental testing – Part 2 -75: Tests – Test Eh: Hammer tests  
IEC 60068 -2-78, Environmental testing – Part 2 -78: Tests – Test Cab: Damp heat, steady state 
IEC TR 60083 , Plugs and socket -outlets for domestic and similar general use standardized in 
member countries of IEC 
IEC 60085:2007, Electrical insulation – Thermal evaluation and designation 
IEC 60112:2003, Method for the determination of the proof and the comparative  tracking indices 
of solid insulating materials   
IEC 60112:2003/AMD1:2009 1 
IEC 60127 (all parts), Miniature fuses  
IEC 60227 (all parts), Polyvinyl chloride insulated cables of rated voltages up to and including 
450/750 V  
IEC 60227 -5:2011, Polyvinyl chloride insulated cables of rated voltages up to and including 
450/750 V – Part 5: Flexible cables (cords ) 
IEC 60238, Edison screw lampholders  
IEC 60245 (all parts), Rubber insulated cables – Rated voltages up to and including 450/750 V  
IEC 60252 -1:2010, AC motor capacitors – Part 1: General – Performance, testing and rating – 
Safety requirements – Guid ance  for installation and operation  
IEC 60252 -1:2010/AMD1:2013 2 
IEC 60309 -2, Plugs, socket -outlets and couplers for industrial purposes – Part 2: Dimensional 
interchangeability requirements for pin and contact -tube accessories  
IEC 60320 (all parts),  Appliance couplers for household and similar general purposes  
IEC 60320 -1, Appliance couplers for household and similar general purpo ses – Part 1: General 
requirements  
IEC 60320 -2-3, Appliance couplers for household and similar general purposes – Part 2 -3: 
Appliance couplers with a degree of protection higher than IPX0  
___________ 
1 There exists a consolidated edition 4.1:2009 that includes edition 4 and its Amendment 1.  
2 There exists a consolidated edition 2.1:2013 that includes edition 2 and its Amendment 1.  IEC 60335- 1:2020 © IEC 2020 – 13 –          IEC 60320 -3, Appliance couplers for household and similar general pu rposes – Part 3: Standard 
sheets and gauges  
IEC 60384 -14:2013, Fixed capacitors for use in electronic equipment – Part 14: Sectional 
specification  – Fixed capacitors for electromagnetic interference suppression and connection 
to the supply mains  
IEC 60384 -14:2013/AMD1:2016 3 
IEC 60417, Graphical symbols for use on equipment  
IEC 60445:201 7, Basic and safety principles for man- machine interface, marking and 
identification – Identification of equipment terminals, conductor terminations and conductors  
IEC 60529:1989, Degrees of protection provided by enclosures (IP Code)  
IEC 60529:1989/AMD1:1999 
IEC 60529:1989/AMD2:2013 4 
IEC 60598 -1:2014,  Luminaires – Part 1: General requirements and tests  
IEC 60598 -1:2014/AMD1:2017 5 
IEC 60603 -11, Connectors for frequencies below 3 MHz for use with printed boards – Part 11: 
Detail specification for concentric connectors (dimensions for free connectors and fixed 
connectors)  
IEC 60664 -1:2007, Insulation coordination for equipment within low -voltage systems – Part 1: 
Principles, requirements and tests  
IEC 60664 -3:2016 , Insulation coordination for equipment within low -voltage systems – Part 3: 
Use of coating, potting or moulding for protection against pollution  
IEC 60664 -4:2005, Insulation coordination for equipment within low -voltage systems – Part 4: 
Consideration of high -frequency voltage stress 
IEC 60691, Thermal -links – Requirements and application guide 
IEC 60695 -2-11:20 14, Fire hazard testing – Part 2 -11: Glowing/hot -wire based test methods – 
Glow -wire flammability test method for end -products  (GWEPT)  
IEC 60695 -2-12, Fire hazard testing – Part 2-12: Glowing/hot -wire based test methods – Glow -
wire flammability index (GWFI) test method for materials  
IEC 60695 -2-13, Fire hazard testing – Part 2 -13: Glowing/hot -wire based test methods – Glow -
wire ignition temperature (GWIT) test method for materials  
IEC 60695 -10-2, Fire hazard testing – Part 10- 2: Abnormal heat – Ball pressure test  
IEC 60695 -11-5:2016, Fire hazard testing  – Part 11 -5: Test flames – Needle- flame test method 
– Apparatus, c onfirmatory test arrangement and guidance  
___________ 
3 There exists a consolidated edition 4.1:2016 that includes edition 4 and its Amendment 1.  
4 There exists a consolidated edition 2.2:2013 that includes edition 2 and its Amendment 1 and Amendment 2.  
5 There exists a consolidated edition 8.1:2017 that includes edition 8 an d its Amendment 1.   – 14 – IEC 60335- 1:2020 ©  IEC 20 20        IEC 60695 -11-10, Fire hazard testing – Part 11 -10: Test flames – 50 W horizontal and vertical 
flame test methods  
IEC 60730 -1:2013,  Automatic electrical controls – Part 1: General requirements  
IEC 60730 -1:2013/AMD1:2015 6 
IEC 60730 -2-8:2018, Automatic electrical controls – Part 2 -8: Particular requirements for 
electrically operated water valves, including mechanical requirements  
IEC 60730 -2-9:2015,  Automatic electrical controls – Part 2 -9: Particular  requirements for 
temperature sensing control s 
IEC 60730 -2-9:2015/AMD1:2018 7 
IEC 60730 -2-10, Automatic electrical controls for household and similar use – Part 2 -10: 
Particular requirements for motor- starting relays  
IEC 60738 -1, Thermistors – Directly heated positive temperature coefficient – Part 1: Generic 
specification  
IEC 60799, Electrical accessories – Cord sets and interconnection cord sets  
IEC 60906 -1, IEC system of plugs and socket -outlets for household and similar purposes –  
Part 1: Plugs and socket -outlets 16 A 250 V a.c.  
IEC 60934, Circuit -breakers for equipment (CBE)  
IEC 60990: 2016 , Methods of measurement of touch current and protective conductor current  
IEC 60999 -1:1999, Connecting devices – Electrical copper conductors – Safety re quirements 
for screw -type and screwless -type clamping units – Part 1: General requirements and particular 
requirements for clamping units for conductors from 0,2 mm2 up to 35 mm2 (included) 
IEC 61000 -4-2, Electromagnetic compatibility (EMC) – Part 4 -2: Tes ting and measurement 
techniques – Electrostatic discharge immunity test  
IEC 61000 -4-3, Electromagnetic compatibility (EMC) – Part 4 -3: Testing and measurement 
techniques – Radiated, radio -frequency, electromagnetic field immunity test  
IEC 61000 -4-4, Electr omagnetic compatibility (EMC) – Part 4 -4: Testing and measurement 
techniques – Electrical fast transient/burst immunity test  
IEC 61000 -4-5, Electromagnetic compatibility (EMC) – Part 4 -5: Testing and measurement 
techniques – Surge immunity test  
IEC 61000 -4-6, Electromagnetic compatibility (EMC) – Part 4 -6: Testing and measurement 
techniques – Immunity to conducted disturbances, induced by radio- frequency fields  
IEC 61000 -4-11:20 20, Electromagnetic compatibility (EMC) – Part 4 -11: Testing and measure -
ment techniques – Voltage dips, short interruptions and voltage variations immunity tests  for 
equipment with input current up to 16 A per phase  
___________ 
6 There exists a consolidated edition 5.1:2015 that includes edition 5 and its Amendment 1.  
7 There exists a consolidated edition 4.1:2018 that includes edition 4 and its Amendment 1.  IEC 60335- 1:2020 © IEC 2020 – 15 –          IEC 61000 -4-13:2002, Electromagnetic compatibility (EMC) – Part 4 -13: Testing and 
measurement techniques – Harmo nics and interharmonics including mains signalling at a.c. 
power port, low frequency immunity tests 
IEC 61000 -4-13:2002/AMD1:2009 
IEC 61000 -4-13:2002/AMD2 :2015 8 
IEC 61000 -4-34:2005 , Electromagnetic compatibility (EMC) – Part 4 -34: Testing and 
measurement techniques – Voltage dips, short interruptions and voltage variations immunity 
tests for equipment with input current more than 16 A per phase 
IEC 61000 -4-34:200 5/AMD1:2009 9 
 
IEC 61032:1997, Protection of persons and equipment by enclosures – Probes for verification 
IEC 61058 -1:2016, Switches for appliances – Part 1: General requirements  
IEC 61058 -1-1:2016, Switches for appliances – Part 1 -1: Requirements for mechanical switches  
IEC 61058 -1-2:2016, Switches for appliances – Part 1 -2: Requirements for electronic switches  
IEC 61180, High -voltage test techniques for low- voltage equipment – Definitions, test and 
procedure requirements, test equipment  
IEC 61210, Connecting devices – Flat quick -connect terminations for electrical copper 
conductors – Safety requirements  
IEC 61558 -1:2017, Safety of transformers, reactors, power supply units and combinations 
thereof – Part 1: General requirements and tests  
IEC 61558 -2-6:2009, Safety of transformers, reactors, power supply units and similar products 
for supply voltages up to 1 100 V – Part 2 -6: Particular requirements and tests for safety 
isolating transformers and power supply units incorporating safety isolating transformers  
IEC 61558 -2-16:2009, Safety of transformers, reactors, power supply units and similar products 
for supply voltages up to 1 100 V – Part 2 -16: Particular requirements and tests for switch mode 
power supply units and transformers for switch mode power supply units   
IEC 61558 -2-16:2009/ AMD1:2013 10 
IEC 61770, Electric appliances connected to the water mains – Avoidance of backsiphonage 
and failure of hose -sets 
IEC 62133 -1:2017, Secondary cells and batteries containing alkaline or other non- acid 
electrolytes – Safety requirements for portable sealed secondary cells, and for batteri es made 
from them, for use in portable applications – Part 1: Nickel systems 
IEC 62133 -2:2017, Secondary cells and batteries containing alkaline or other non- acid 
electrolytes – Safety requirements for portable sealed secondary cells, and for batteries mad e 
from them, for use in portable applications – Part 2: Lithium systems  
IEC 62151, Safety of equipment electrically connected to a telecommunication network  
___________ 
8 There exists a consolidated edition 1.2:2015 that includes edition 1 and its Amendment 1 and Amendment 2.  
9 There exists a consolidated edition 1.1 :2009  that includes edition 1 and its Amendment 1.  
10 There exists a consolidated edition 1.1:2013 that includes edition 1 and its Amendment 1.   – 16 – IEC 60335- 1:2020 ©  IEC 20 20        IEC 62471:2006, Photobiological safety of lamps and lamp systems  
IEC 62477 -1, Safety requirements for power electronic converter systems and equipment –  
Part 1: General  
IEC 62821 (all parts), Electric cables – Halogen- free, low smoke, thermoplastic insulated and 
sheathed cables of rated voltages up to and including 450/750 V  
ISO 178, Plastics – Determination of flexural properties 
ISO 179- 1, Plastics – Determination of Charpy impact properties – Part 1: Non- instrumented 
impact test  
ISO 180, Plastics – Determination of Izod impact strength  
ISO 527 (all parts), Plastics – Determinatio n of tensile properties  
ISO 1463, Metallic and oxide coatings – Measurement of coating thickness – Microscopical 
method  
ISO 2178, Non-magnetic coatings on magnetic substrates – Measurement of coating thickness 
– Magnetic method  
ISO 2768 -1, General tolerances – Part 1: Tolerances for linear and angular dimensions without 
individual tolerance indications  
ISO 4892 -1:2016, Plastics – Methods of exposure to laboratory light sources – Part 1: General 
guidance 
ISO 4892 -2: 2013, Plastics – Methods of exposure to laboratory light sources – Part 2: Xenon-
arc lamps  
ISO 7000, Graphical symbols for use on equipment – Registered symbols  
ISO 8256, Plastics – Determination of tensile- impact strength 
ISO 9772, Cellular plastics – Determination of horizontal bur ning characteristics of small 
specimens subjected to a small flame  
ISO 9773, Plastics – Determination of burning behaviour of thin flexible vertical specimens in 
contact with a small -flame ignition source  
3 Terms and definitions  
For the purposes of this document, the following terms and definitions apply.  
ISO and IEC maintain terminological databases for use in standardization at the following 
addresses:  
• IEC Electropedia: available at http://www.electropedia.org/  
• ISO Online browsing platform: available at http://www.iso.org/obp  
When the terms " voltage" and "current " are used, they are RMS  values, unless otherwise 
specified.  IEC 60335- 1:2020 © IEC 2020 – 17 –          When the term "earthing" is used, it means "protectiv e earthing ", unless otherwise specified.  
3.1 Definitions relating to physical characteristics  
3.1.1   
rated voltage  
voltage assigned to the appliance by the manufacturer  
3.1.2   
rated voltage range  
voltage range assigned to the appliance by the manufacturer, expressed by it s lower and upper 
limits 
3.1.3   
working voltage  
maximum voltage to which the part under consideration is subjected when the appliance is 
supplied at its rated voltage and operating under normal operation , with controls and 
switching devices positioned so as to m aximize the value 
Note 1 to entry:  Working voltage takes into account resonant voltages.  
Note 2 to entry:  When deducing the working voltage, the effect of transient voltages is ignored.  
3.1.4   
rated power input  
power input assigned to the appliance by the manufacturer  
Note 1 to entry:  If no power input is assigned to the appliance, the rated power input  for heating appliances and 
combined appliances  is the power input measured when the appliance is supplied at rated voltage and operated 
under normal operation. 
3.1.5   
rated power input range power input range assigned to the appliance by the manufacturer, expressed by its lower and 
upper limits  
3.1.6   
rated curre nt 
current assigned to the appliance by the manufacturer  
Note 1 to entry: If no current is assigned to the appliance, the rated current is the current measured when the  
appliance is supplied at rated voltage and operated under normal operation . 
3.1.7   
rated frequency frequency assigned to the appliance by the manufacturer  
3.1.8   
rated frequency range 
frequency range assigned to the appliance by the manufacturer, expressed by its lower and 
upper limits  
3.1.9   
normal operation  
conditions under which the appliance is operated in normal use when it is connected to the 
supply mains  
Appliances operated with integral batteries or separable batteries not disconnected from the 
appliance for charging purposes:   – 18 – IEC 60335- 1:2020 ©  IEC 20 20        – the battery  that is fully discharged  is charged with the battery -operated appliance 
performing its intended function, if allowed by the construction of the appliance ; 
– the battery  that is fully discharged  is charged without the battery- operated appliance 
performing its intended function  
Note 1 to entry: Operation of a battery -operate d appliance  to perform its intended function is considered to be 
normal operation. 
3.1.10   
rated impulse voltage  
voltage derived from the rated voltage  and the overvoltage category of the appliance, 
characterizing the specified withstand capability of its insulation against transient over voltages  
3.1.11   
dangerous malfunction  
unintended operation of the appliance that may impair safety  
3.1.12   
outlet load  
load that can be connected to appliance outlets accessible to the user and socket -outlets 
accessible to the user 
Note 1 to entry:  Outlets with a voltage not exceeding SELV  are not considered to be an appliance outlet.  
3.2 Definitions relating to means of connection 
3.2.1   
supply leads  
set of wires intended for connecting the appliance to fixed wiring and accommodated in a 
compartment within or attached to the appliance 
3.2.2   
interconnection cord  
external flexible cord between two part s of an appliance, provided as part of a complete 
appliance for purposes other than connection to the supply mains  
Note 1 to entry: In battery -operated appliances, if the battery  is placed in a separate box, the flexible lead or 
flexible cord connecting the box with the appliance is considered to be an interconnection  cord. 
Note 2 to entry: The output cord from a charging system  or a detachable power supply part  is an 
interconnection cord . 
3.2.3   
supply cord 
flexible cord, for supply purposes, that is fixed to the appliance 3.2.4   
type X attachment 
method of attachment of the supply cord such that it can easily be replaced  
Note 1 to entry:  The supply cord may be specially prepared and only available from the manufacturer or its service 
agent. A specially prepared cord may include a part of the appliance.  
3.2.5   
type Y attachment 
method of attachment of the supply cord  such that any replacement is intended to be made by 
the manufacturer, its service agent or similar qualified person IEC 60335- 1:2020 © IEC 2020 – 19 –          3.2.6   
type Z attachment  
method of attachment of the supply cord  such that it cannot be replaced without breaking or 
destroying the appliance  
3.3 Definitions relating to protection against electric shock  
3.3.1   
basic insulation  
insulation applied to live parts  to provide basic protection against electric shock  
3.3.2   
supplementary insulation 
independent insulation applied in addition to basic insulation , in order to provide protection 
against electric shock in the event of a failure of basic insulation  
3.3.3   
double insulation insulation system comprising both basic insulation  and supplementary insulation  
3.3.4   
reinforced insulation  
single insulation applied to live parts , that provides a degree of protection against electric 
shock equivalent to double insulation under the conditions specified in this standard 
Note 1 to entry:  It is not implied that the insulation is one homogeneous piece. The insulation may comprise several 
layers which cannot be tested singly as supplementary insulation  or basic insulation . 
3.3.5   
functional insulation  
insulation between conductive parts of different potential which is necessary only for the proper functioning of th e appliance 
3.3.6   
protective impedance impedance connected between live parts and accessible conductive parts of class II 
constructions so that the current, in normal use and under likely fault conditions in the 
appliance, is limited to a safe value  
3.3.7   
class 0 appliance 
appliance in which protection against electric shock relies upon basic insulation only, there 
being no means for the connection of conductive accessible parts , if any, to the protective 
conductor in the fixed wiring of the installation, reliance in the event of a failure of the basic 
insulation being placed upon the environment  
Note 1 to entry: Class 0 appliances  have either an enclosure of insulating material which may form a part or the 
whole of the basic insulation , or a metal enclosure which is separated from live parts by an appropriate insulation. 
If an appliance with an enclosure of insulating material has provision for earthing internal parts, it is considered to 
be a class I appliance or class 0I appliance . 
3.3.8   
class 0I appliance 
appliance having at least basic insulation throughout and incorporating an earthing terminal 
but having a supply cord  without earthing conductor an d a plug without earthing contact  
3.3.9   
class I appliance 
appliance in which protection against electric shock does not rely on basic insulation  only but 
which includes an additional safety precaution, in that conductive accessible parts are  – 20 – IEC 60335- 1:2020 ©  IEC 20 20        connected to the pr otective earthing conductor in the fixed wiring of the installation in such a 
way that conductive accessible parts cannot become live in the event of a failure of the basic 
insulation  
Note 1 to entry:  This provision include s a protective earthing conductor in the supply cord . 
3.3.10   
class II appliance  
appliance in which protection against electric shock does not rely on basic insulation  only but 
in which additional safety precautions are provided, such as double insulation  or reinforced 
insulation, there being no provision for protective earthing or reliance upon installation 
conditions  
Note 1 to entry:  Such an appliance may be of one of the following types:  
– an appliance having a durable and substantially continuous enclosure of insulating material which envelops all 
metal parts, with the exception of parts, such as nameplates, screws and rivets, which are isolated from live 
parts  by insulation at least equivalent to reinforced insulation ; such an appliance is called an insulation-
encased class II appliance; 
– an appliance having a substantially continuous metal enclosure, in which double insulation or reinforced 
insulation  is used throughout; such an appliance i s called a metal -encased class II appliance; 
– an appliance which is a combination of an insulation- encased class II appliance and a metal -encased class II 
appliance. 
Note 2 to entry: The enclosure of an insulation- encased class II appliance may form a part or the whole of the 
supplementary insulation  or of the reinforced insulation . 
Note 3 to entry:  Class II appliances may incorporate an earth for functional purposes.  
3.3.11   
class II construction  
part of an appliance for which protection against electric shock relies upon double insulation  
or reinforced insulation 
3.3.12   
class III appliance  
appliance in which protection against electric shock relies on supply at safety extra- low 
voltage and in which volt ages higher than those of safety extra -low voltage  are not generated 
Note 1 to entry:  Basic insulation  may be required in addition to supply at SELV. Refer to 8.1.4 . 
Note 2 to entry:  Class III appliances  may incorporate an earth for functional purposes . 
3.3.13   
class III construction  
part of an appliance for which protection against electric shock relies upon safety extra- low 
voltage and in which voltages higher than those of safety extra -low voltage  are not generated 
Note 1 to entry:  Basic insulation  may be required in addition to supply at SELV. Refer to 8.1.4 . 
3.3.14   
clearance 
shortest distance in air between two conductive parts or between a conductive part and the 
accessible surface  
3.3.15   
creepage distance  
shortest distance along the surface of insulation between two conductive parts or between a conductive part and the accessible surface IEC 60335- 1:2020 © IEC 2020 – 21 –          3.4 Definitions relating to extra -low voltage  
3.4.1   
extra- low voltage  
voltage supplied from a source within the appliance that does not exceed 50 V between 
conductors and between co nductors and earth or functional earth when the appliance is 
supplied at rated voltage 
3.4.2   
safety extra- low voltage  
voltage not exceeding 42 V between conductors and between conductors and earth  or 
functional earth , the no- load voltage not exceeding 50 V 
Note 1 to entry: When safety extra- low voltage is obtained from the supply mains, it is to be through a safety 
isolating transformer  or a convertor with separate windings, the insulation of which complies with double insulation  
or reinforced insulation  requirements.  
Note 2 to entry:  The voltage limits specified are based on the assumption that the safety isolating transformer  is 
supplied at its  rated voltage. 
Note 3 to entry:  Safety extra -low voltage is also known as SELV. 
3.4.3   
safety isolating transformer  
transformer, the input winding of which is electrically separated from the output winding by an 
insulation at least equivalent to double i nsulation  or reinforced insulation , that is intended 
to supply an appliance or circuit at safety extra- low voltage  
3.4.4   
protective extra -low voltage circuit  
earthed circuit operating at extra- low voltage that is separated from other circuits, except 
circuits operating at safety extra -low voltage, by basic insulation  and protective screening, 
double insulation  or reinforced insulation  
Note 1 to entry:  Protective screening is the separation of circuits from live parts by means of an earthed screen.  
Note 2 to entry:  A protective extra- low voltage circuit is also known as a PELV circuit . 
3.5 Definitions relating to types of appliances  
3.5.1   
portable appliance  
appliance that is intended to be moved while in operation or an appliance, other than a fixed 
appliance,  having a mass less than 18 kg 
3.5.2   
hand -held appliance  
portable appliance intended to be held in the hand during normal use  
3.5.3   
stationary appliance  
fixed appliance or an appliance which is not a portable appliance 
3.5.4   
fixed appliance 
appliance that is intended to be used while fastened to a support or while secured in a specific 
location  
3.5.5   
built -in appliance  
fixed appliance intended to be installed in a c abinet, in a prepared recess in a wall or in a 
similar location   – 22 – IEC 60335- 1:2020 ©  IEC 20 20        3.5.6   
heating appliance 
appliance incorporating heating elements but without any motor  
3.5.7   
motor -operated appliance 
appliance incorporating motors but without any heating element  
Note 1 to entry:  Magnetically driven appliances are considered to be motor -operated appliances. 
3.5.8   
combined appliance  
appliance incorporating heating elements and motors  
3.5.9   
battery -operated appliance  
appliance deriving its energy from batteries  enabling the appliance to perform its intended 
function without a supply connection  
Note 1 to entry:  A battery -operated appliance can have a supply connection.  
3.6 Definitions relati ng to parts of an appliance  
3.6.1   
non-detachable part  
part that can only be removed or opened with the aid of a tool  or part that fulfils the test of 
22.11  
3.6.2   
detachable part  
part that can be removed or opened without the aid of a tool, part that is removed or opened in 
accordance with the instructions for use, even if a tool is needed for removal, or part that does 
not fulfil the test of 22.11 
Note 1 to entry:  If for installation purposes a part has to be removed, this part is not considered to be  a detachable 
part  even if the instructions state that it is to be removed.  
Note 2 to entry:  Components that can be removed without the aid of a tool  are considered to be detachable parts. 
Note 3 to entry:  If a part has to be removed solely to discard a battery  before scrapping the appliance, this part is 
not considered to be a detachable part  even if the instructions state that it is to be removed. 
3.6.3   
accessible part 
part or surface that can be touched by means of test probe B of IEC 61032, and if the part or 
surface is metal, any conductive part connected to it  
Note 1 to entry: Accessible non -metallic parts with conductive coatings are  considered to be accessible metal 
parts . 
3.6.4   
live part  
conductor or conductive part intended to be energized in normal use, including a neutral 
conductor but, by convention, not a PEN conductor  
Note 1 to entry:  Parts, accessible or not, complying with 8.1.4 are not considered to be live parts . 
Note 2 to entry: A PEN conductor is a protective earthed neutral conductor combining the functions of both a 
protective conductor and a neutral conductor.  
Note 3 to entry: Parts, whether they are accessible  parts  or not, of battery -operated appliances and batteries  
not exceeding the electrical limits of B.22.3  and B.22.4 , are not considered to be live parts. IEC 60335- 1:2020 © IEC 2020 – 23 –          3.6.5   
tool 
screwdriver, coin or any other object that may be used to operate a screw or similar fixing 
means  
3.6.6   
small part  
part, where each surface lies completely within a circle of 15 mm diameter, or part where some 
of the surface lies outside a 15 mm diameter circle but in such a way that it is not possible to 
fit a circle of 8 mm diameter on any of the surfaces 
Note 1 to entry:  A part that is too small to grip and at the same time to be able to apply the glow -wire tip is shown 
in example A in Figure 5. A part that is large enough to grip but that is too small to be able to apply the glow -wire tip 
is shown in example B in Figure 5. A part that is not a small part  is shown in example C in Figure 5. 
3.6.7   
detachable power supply part  
part of the appliance the output of which is intended to be detachable from the class III construction part of the appliance 
Note 1 to entry: Means of detachment are a flexible cord and connector or an appliance outlet fitted to the 
detachable power supply part . 
3.6.8   
cell 
basic functional unit, consisting of an assembly of elect rodes, electrolyte, container, terminals, 
and usually separators that is a source of electric energy obtained by direct conversion of 
chemical energy  
[SOURCE: IEC 60050- 482:2004, 482- 01-01] 
3.6.9   
battery 
assembly of one or more cells  ready for use as a source of electrical energy, characterised by 
its voltage, size, terminal arrangement, capacity and rate capability 
Note 1 to entry:  A detachable battery and separable battery have an enclosure that is equivalent in properties to 
that of the appliance itself, but integral batteries may have no enclosure or an enclosure less substantial than that 
of the appliance, as they are protected by the enclosure of the appliance.  
3.6.10   
detachable battery 
rechargeable battery in an enclosure separate from the battery- operated appliance , intended 
for use with specific appliances and intended to be removed from the appliance for charging 
purposes  
Note 1 to entry:  A standard automotive battery is not considered a detachable battery. 
Note 2 to entry:  A detachable battery  is not considered a battery  that is replaceable.  
3.6.11   
separable battery  
battery  contained in an enclosure separate from the battery- operated appliance, intended for 
use with specific appliances and connected to the appliance by a cord external to the enclosure of the appliance 
Note 1 to entry:  A standard automotive battery is not considered a separable battery . 
Note 2 to entry:  A separable battery is not considered a battery  that is replaceable.  – 24 – IEC 60335- 1:2020 ©  IEC 20 20        3.6.12   
integral battery  
battery  contained within the battery -operated appliance  and not removed from the appliance 
for charging purposes 
Note 1 to entry:  A battery  that is only to be removed from the battery -operated appliance for disposal or recycling 
is still considered to be an integral battery.  
3.7 Definitions relating to safety components  
3.7.1   
thermostat  
temperature -sensing device, the operating temperature of which ma y be either fixed or 
adjustable and which during normal operation  keeps the temperature of the controlled part 
between certain limits by automatically opening and closing a circuit  
3.7.2   
temperature limiter 
temperature -sensing device, the operating temperature of which may be either fixed or 
adjustable and which during normal operation  operates by opening or closing a circuit when 
the temperature of the controlled part reaches a pre- determined value 
Note 1 to entry: A temperature  limiter  does not make the reverse operation during the normal duty cycle of the 
appliance. It may or may not require manual resetting.  
3.7.3   
thermal cut -out 
device which during abnormal operation limits the temperature of the controlled part by automatically o pening the circuit, or by reducing the current, and is constructed so that its 
setting cannot be altered by the user 
3.7.4   
self-resetting thermal cut -out 
thermal cut -out that automatically restores the current after the relevant part of the appliance 
has cooled down sufficiently  
3.7.5   
non-self-resetting thermal cut -out 
thermal cut -out that requires a manual operation for resetting, or replacement of a part, in 
order to restore  the current  
Note 1 to entry:  Manual operation includes disconnection of the appliance from the supply mains.  
3.7.6   
protective device 
device, the operation of which prevents a hazardous situation under abnormal operation 
conditi ons 
3.7.7   
thermal link  
thermal cut -out which operates only once and requires partial or complete replacement  
3.7.8   
intentionally weak part  
part intended to rupture under conditions of abnormal operation to prevent the occurrence of a condition which could impair com pliance with this standard 
Note 1 to entry: Such a part may be a replaceable component, such as a resistor or a capacitor, or a part of a 
component to be replaced, such as a thermal link that is not an accessible part  incor porated in a motor.  IEC 60335- 1:2020 © IEC 2020 – 25 –          3.8 Definitions relating to miscellaneous matters  
3.8.1   
all-pole disconnection  
disconnection of both supply conductors by a single initiating action or, for multi -phase 
appliances, disconnection of all supply conductors by a single initiating ac tion 
Note 1 to entry:  For multi -phase appliances, the neutral conductor is not considered to be a supply conductor.  
3.8.2   
off position 
stable position of a switching device in which the circuit controlled by the switch is disconnected 
from its supply or, for electronic disconnection, the circuit is de -energized 
Note 1 to entry:  The off position does not imply an all -pole disconnection. 
3.8.3   
visibly glowing heating element  
heating element that is partly or completely visible from the outside of the appliance and has a 
temperature of at least 650 °C when the appliance has been operated under normal operation 
at rated power input  until steady conditions have been established 
3.8.4   
PTC heating elem ent 
element intended for heating consisting mainly of positive temperature coefficient resistors that 
are thermally sensitive and have a rapid non- linear increase in resistance when the temperature 
is raised through a particular range  
3.8.5   
user maintenance 
any maintenance operation stated in the instructions for use, or marked on the appliance, that 
the user is intended to perform  
3.8.6   
room temperature ambient temperature specified in the general conditions for the tests 
Note 1 to entry:  The ambient temperature is specified in 5.7. 
3.9 Definitions relating to electronic circuits  
3.9.1   
electronic component  
part in which conduction is achieved principally by electrons moving through a vacuum, gas or semiconductor  
Note 1 to entry:  Neon indicators are not considered to be electronic components . 
3.9.2   
electronic circuit  
circuit incorporating at least one electronic component  
3.9.3   
protective electronic circuit electronic circuit  that prevents a hazardous situation under abnormal operating conditions  
Note 1 to entry:  Parts of the circuit may also be used for functional purposes.   – 26 – IEC 60335- 1:2020 ©  IEC 20 20        3.10 Definitions relating to battery charging and discharging  
3.10.1   
battery system  
system that includes a battery , charging system  and the battery -operated appliance   
Note 1 to entry: The battery system , including interfaces, may contain more than one battery  and charging 
system.  
3.10.2   
charging system  
circuitry that charges and maintains the state of charge of the battery  
Note 1 to entry:  Parts of the charging system may perform other functions such as charge balancing and may be 
separately enclosed.  
3.10.3   
specified operating region for charging  
region during charging in which a cell operates within its voltage and current range as specified 
by the cell manufacturer 
Note 1 to entry: An example of a specified operating region of a lithium -ion cell during charging is shown in  
Figure 14. 
3.10.4   
upper limit charging voltage  
highest charging voltage in the specified operating region for charging  
3.10.5   
venting 
condition intended by design that occurs when a cell provides a controlled release of excessive 
internal pressure without expulsion of major components of the cell 
3.10.6   
fully charged 
at the maximum state of charge  
Note 1 to entry: For cells and batteries that are rechargeable, t his is the maximum state of charge permitted by 
the charging system . 
Note 2 to entry:  The maximum state of charge for non- rechargeable batteries  and batteries that are rechargeable  
is specified in the artificial source character istics of Table B.1 . 
3.10.7   
fully discharged  
discharged at a steady rate of current to attain, at 5 h of steady discharge (C5 rate), or the 
fastest discharge rate allowed by the cell manufacturer or battery  manufacturer if it is slower 
than the C5 rate, until  
− discharge terminates due to operation of discharge termination circuitry; or  
− the battery  (or cell) reaches a total voltage with an average voltage per cell  equal to the 
end- of-discharge voltage for the cell  chemistry being used, unless a different end of 
discharge voltage is specified by the  cell manufacturer 
Note 1 to entry: Examples of the end- of-discharge voltages for fully discharged  common cell chemistries are 
typically 
– 0,9 V/cell for nickel cadmium;  
– 0,9 V/cell for nickel metal -hydride;  
– 1,75 V/cell for lead- acid; 
– 2,5 V/cell for lithium iron- phosphate;  IEC 60335- 1:2020 © IEC 2020 – 27 –          – 3,0 V/cell for lithium cobalt- oxide.  
3.11 Definitions relating to remote functionality  
3.11.1   
entity  
person, device, appliance, product, or service that interacts with an appliance  
3.11.2   
message 
data which is transmitted from a sender (data source) to one or more receivers (data sink)  
3.11.3   
public  network  
network carrying digital data or analogue signals or both where access to the data and signals is not restricted by the physical space within the household or similar use environment of the 
appliance 
Note 1 to entry:  Determination of confinement to the physical space includes consideration of the network’s range 
of commu nication, configuration, or construction.  
For the purposes of this standard, examples of public networks  include but are not limited to: 
– PAN (personal area network);  
– LAN (local area network) connected devices which may or may not be connected to a gateway,  
– PLC (power line communication);  
– SRD (short range devices);  
– WAN (wide area network);  
For the purposes of this standard, examples  of networks which are not considered as being  public  networks  include  
but are not limited  to: 
– NFC (near field communication);  
– optical communication with line of sight (infra -red rays or visual rays);  
– hardwired configurations constructed of physical media;  
without connection to a public network. 
3.11.4   
remote  communication  
transmission of data between the appliance and an entity  that can be initiated out of sight of 
the appliance, using communication means such as radio wave modulation, sound wave modulation or bus systems  
Note 1 to entry: Examples of transmission of data includes but are not limited to remote monitoring, software 
downloading or control parameter modifications.  
Note 2 to entry:  Transmission of data can be one- way (simplex) or two -way (duplex).  
3.11.5   
remo te operation  
control of an appliance by remote  communication  
Note 1 to entry: Remote communication that results in a change of appliance operation, such as change of 
rotational speed, temperature, spatial movement, start/stop of the intended function, is considered remote operation. 
It is possible to have remote communication that does not lead to remot e operation.  
Note 2 to entry:  A line of sight  infra- red signal  by itself  is not considered one used for remote  operation.  – 28 – IEC 60335- 1:2020 ©  IEC 20 20        4 General requirement  
Appliances shall be constructed so that in normal use, they function safely so as to cause no 
danger to persons or surroundings, even in the event of carelessness that may occur in normal 
use. 
In general, this principle is achieved by fulfilling the relevant requirements specified in this 
standard and compliance is checked by carrying out all the relevant tests.  
5 General conditions for the tests  
Unless otherwise specified, the tests are carried out in accordance with this clause.  
5.1 Tests according to this stan dard are type tests . 
NOTE  Routine tests are described in informative Annex  A. 
5.2 The tests are carried out on a single appliance that shall withstand all the relevant t ests. 
However, the tests of Clauses 12, 20, 22 (except 22.10, 22.11 and 22.18 ) to 26, 28, 30 and 31 
may be carried out on separate appliances. The test of 22.3  is carried out on a new appliance.  
If an intentionally weak part  becomes open circuit during the tests of Clause  19, an additional 
appliance may be needed . 
The testing of components may require the submission of additional samples of these components.  
If the test of normative Annex  C has to be carried out, six samples of the motor are needed.  
If the test of normative Annex  D has to b e carried out, an additional appliance may be used. 
If the tests of normative Annex  G are carried out, four additional transformers are needed.  
If the tests of normat ive Annex  H are carried out, three switches or three additional appliances 
are needed.  
NOTE  Additional samples can be required if the appliance has to be tested under  different conditions, for example 
if it can be supplied with different voltages.  
The cumulative stress resulting from successive tests on electronic circuits  shall be avoided. 
It may be necessary to replace components or to use additional samples. The number of 
additional samples shall be kept to a minimum by an evaluation of the relevant electronic 
circuits.  
If an appliance has to be dismantled in order to ca rry out a test, care shall be taken to ensure 
that it is reassembled as originally supplied. In case of doubt, subsequent tests may be carried out on a separate sample.  
5.3 The tests are carried out in the order of the clauses. However, the test of 22.11  on the 
appliance at room temperature is carried out before the tests of Clause  8. The tests of 
Clause  14, 21.2 and 22.24 are carried out after the tests of Clause  29. The test of 19.14 is 
carried out before the tests of 19.11.  
If it is evident from the construction of the appliance that a particular test is not applicable, the test is not carried out.  IEC 60335- 1:2020 © IEC 2020 – 29 –          5.4 When testing appliances that are also supplied by other energies such as gas, the 
influence of their consumption has to be taken into account.  
5.5 The tests are carried out with the appliance or any movable part of it placed in the most 
unfavourable position t hat may occur in normal use.  
5.6 Appliances provided with controls or switching devices are tested with these controls or 
devices adjusted to their most unfavourable setting, if the setting can be altered by the user.  
If the adjusting means of the control is accessible without the aid of a tool, this subclause 
applies whether the setting can be altered by hand or with the aid of a tool.  If the adjusting 
means is not accessible without the aid of a tool and if the setting is not intended to be altered 
by the user, this subclause does not apply.  
NOTE  Adequate sealing is regarded as preventing alteration of the setting by the user.  
For appliances fitted with a voltage selector switch, the tests are carried out with the switch in 
the position corresponding to the rated voltage value used for the tests.  
5.7 The tests are carried out in a draught -free location at an ambient temperature of 
20 °C ± 5 °C. 
If the temperature attained by any part is limited by a temperature sensitive device or is 
influenced by the temperature at which a change of state occurs, for example when water boils, 
the ambient temperature is maintained at 23 °C ± 2 °C in case of doubt.  
5.8 Test conditions relating to frequency and voltage  
5.8.1  Appliances for alternating current ( AC) only are tested with AC  at rated frequency , 
and those for AC and DC are tested at the more unfavourable supply.  
Appliances for AC that are not marked with rated frequency or are marked with a rated 
frequency range of 50  Hz to 60  Hz are tested with either 50  Hz or 60 Hz, whichever is the 
more unfavourable.  
5.8.2  Appliances having more than one rated voltage are tested on the basis of the most 
unfavourable voltage.  
For motor- operated appliances , and combined appliances , marked with a rated voltage 
range, when it is specified that the supply voltage is equal to the rated voltage  multiplied by a 
factor, the appliance is supplied at  
– the upper limit of the rated voltage range multiplied by this factor, if greater than 1;  
– the lower limit of the rated voltage range  multiplied by this factor, if smaller than 1.  
When a factor is not specif ied, the supply voltage is the most unfavourable within the rated 
voltage range . 
If a heating appliance  has a rated voltage range , the upper limit of the voltage range will 
usually be the most unfavourable voltage within the range. For motor -operated appliances , 
combined appliances  and appliances having more than one rated voltag e or rated voltage 
range, it may be necessary to make some of the tests at the minimum, the mean and the 
maximum values of the rated voltage or the rated voltage range in order to establish the most 
unfavourable voltage.   – 30 – IEC 60335- 1:2020 ©  IEC 20 20        5.8.3  For heating appliances, and combined appliances, marked with a rated power 
input range , when it is specified that the power input is equal to the rated power input  
multiplied by a factor, the appliance is operated at  
– the upper limit of the rated power input range  multiplied by this factor, if greater than 1;  
– the lower limit of the rated power input range  multiplied by this factor, if smaller than 1.  
When a factor is not specified, the power input is the most unfavourable within the rated power 
input range. 
5.8.4  For appliances marked with a rated voltage range  and rated power input  
corresponding to the mean of the rated voltage range, when it is specified that the power input 
is equal to rated power input  multiplied by a factor, the appliance is operated at : 
– the calculated power input corresponding to the upper limit of the rated voltage range  
multiplied by this factor, if greater than 1;  
– the calculated power input corresponding to the lower limit of the rated voltage range 
multiplied by this factor, if smalle r than 1.  
When a factor is not specified, the power input corresponds to the power input at the most 
unfavourable voltage within the rated voltage range . 
5.9 When alternative heating elements or accessories are made available by the appliance 
manufacturer, the appliance is tested with those elements or accessories which give the most 
unfavourable results.  
5.10 The tests are carried out on the appliance as supplied. However, an appliance 
constructed as a single appliance but supplied in a number of units is tested af ter assembly in 
accordance with the instructions provided with the appliance.  
A class III construction  part of the appliance is tested connected to its detachable power 
supply part  taking into account the instructions provided with the appliance.  
Built -in appliances and fixed appliances are installed in accordance with the instructions 
provided with the appliance before testing.  
If batteries  intended for use with the appliance use metal -ion chemistry, the manufacturer or 
responsible agent shall provide the following information for each type of battery 
– end- of-discharge voltage;  
– upper limit charging voltage , for batteries  comprising series connected cells; 
– rated capacity of the battery  (C5 Ah). 
If cells intended for use with the appliance use metal -ion chemistry, the manufacturer or 
responsible agent shall provide the specified operating region for charging for each type of 
cell. 
5.11 Appliances intended to be connected to fixed wiring by means of a flexible cord are tested 
with the appropriate flexible cord connected to the appliance.  
5.12 For heating appliances  and combined appliances , when it is specified that the 
appliance has to  operate at a power input multiplied by a factor, this applies only to heating 
elements without appreciable positive temperature coefficient of resistance.  
For heating elements with appreciable positive temperature coefficient of resistance, other than PTC  heating elements , the supply voltage is determined by supplying the appliance at rated 
voltage until the heating element reaches its operating temperature. The supply voltage is then IEC 60335- 1:2020 © IEC 2020 – 31 –          rapidly increased to the value necessary to give the power input require d for the relevant test, 
this value of the supply voltage being maintained throughout the test.  
NOTE  In general, the temperature coefficient is considered to be appreciable if, at rated voltage, the power input 
of the appliance in cold condition differs by  more than 25 % from the power input at operating temperature. 
5.13 The tests for appliances with PTC heating elements  and for heating appliances  and 
combined appliances  where the heating elements are supplied via a switch mode power 
supply are carried out at a voltage corresponding to the specified power input.  
When a power input greater than the rated power input  is specified, the factor for multiplying 
the voltage is equal to the square root of the factor for multiplying the power input.  
5.14 If class 0I  appliance s or class I appliances  have accessible metal parts that are not 
earthed and are not separated from live parts  by an intermediate metal part that is earthed, 
such parts are checked for compliance with the appropriate requirements specified for class II 
construction . 
If class 0I  appliances or class I appliances  have accessible non -metallic parts , such parts 
are checked for compliance with the appropriate requirements specified for class II 
construction  unless these parts are separated from live parts by an i ntermediate metal part 
that is earthed.  
NOTE  Guidance is given in informative Annex  P for enhanced requirements that can be used to ensure an 
acceptable level of protection against electrical and thermal hazards for particular types of appliances used in an 
installation without a protective earthing conductor in countries that have tropical  climates.  
5.15 If appliances have parts operating at safety extra- low voltage , such parts are checked 
for compliance with the appropriate requirements specified for class III construction . 
5.16 When te sting electronic circuits , the supply is to be free from perturbations from 
external sources that can influence the results of the tests.  
5.17 Battery- operated appliances  and remote controls containing batteries  are tested in 
accordance with  normative Annex  B. 
Battery -operated appliance s having a functional earth connection or a supply connection are 
tested in accordance with the relevant clauses of the main part of this standard and normative  
Annex  B. 
NOTE  A supply connection can include a mains connection.  
Battery -operated appliance s having a supply connection are considered dual supply 
appliances . Dual supply appliances are regarded as battery -operated appliances when 
deriving their energy from batteries . 
Separable batteries and detachable batteries  for battery -operated appliances  are tested in 
accordance with normative Annex  B. 
5.18 To condition batteries  that are rechargeable, the batteries  shall be fully discharged  
and then fully charged in accordance with the appliance manufacturer’s instructions. The 
sequence shall be repeated at least 2  h after the battery  was charged.  
For batteries  where there is a series arrangement of parallel clusters of cells , the cluster shall 
be treated as a single  cell for those tests that require altering the amount of charge on a single  
cell prior to conducting the test.  
5.19 Measurements of cell voltages or battery  voltages shall be made using a single pole 
resistive -capacitive low pass filter with a –3 dB roll off frequency of 5 kHz ± 0,5 kHz. To  – 32 – IEC 60335- 1:2020 ©  IEC 20 20        determine if the upper limit charging voltage  has been exceeded, the peak value of the filtered 
voltage shall be measured with a tolerance of ±1 %. 
When measuring cell voltages or battery  voltages, the peak value of any superimposed ripple 
exceeding 10  % of the average value shall be included. Transi ent voltages are ignored, such 
as a temporary increase of voltage, for example, after the battery is removed from the charging 
system . 
5.20 If linear and angular dimensions are specified without a tolerance, ISO  2768 -1 is 
applicable.  
5.21 Probes are applied with a force not exceeding 1 N. 
5.22 If a component or part of the appliance has both a self -resetting feature and a non-
self-resetting feature  and if the non- self-resetting feature  is not required in order to comply 
with this standard, then appliances incorporating such a component or part shall be tested with 
the non- self-resetting feature rendered inoperative.  
6 Classification  
6.1 Appliances shall be of one of the following classes with respect to protection against 
electric shock:  
class 0, class 0I , class I , class II , class III . 
If an appliance consists of a part of class III construction and a detachable power supply 
part, the complete appliance is classified as a class I appliance  or class II appliance  in 
accordance with the classification applicable to its detachable  power supply part . 
Compliance is checked by inspection and by the relevant tests.  
6.2 Appliances shall have the appropriate degree of protection against harmful ingress of 
water.  
Compliance is checked by inspection and by the r elevant tests.  
NOTE  The degrees of protection against harmful ingress of water are given in IEC  60529 :1989 including 
IEC 60529:1989/AMD1:199 9 and IEC  60529:1989/AMD2:2013 . 
7 Marking and instructions  
7.1 Appliances shall be marked with the: 
– rated voltage or rated voltage range  in volts;  
– symbol for nature of supply, unless the rated frequency  is marked;  
– rated power  input  in watts or rated current  in amperes;  
– name, trade mark or identification mark of the manufacturer or responsible vendor;  
– model or type reference;  
– symbol IEC 60417- 5172 (2003- 02) for class II appliances  only;  
– IP number according to degree of protection against ingress of water, other than IPX0;  
– symbol IEC 60417- 5180 (2003- 02), for class III appliances . This marking is not necessary 
for appliances operated only by batteries  (primary  batteries  or secondary  batteries 
recharged outside of the appliance)  or appliances powered by rechargeable batteries 
recharged in the appliance . IEC 60335- 1:2020 © IEC 2020 – 33 –          NOTE  If the appliance is marked with rated pressure, the units used can be bars but only together with pascals and 
placed in brackets.  
Appliance outlets accessible to the user and socket -outlets accessible to the user : 
– that are incorporated in appliances connected to the supply mains; and  
– that operate at rated voltage  
shall be marked with their outlet load  in watts or amperes.  
Appliances intended to be supplied from a detachable power supply part for the purposes of 
recharging the battery shall be marked with s ymbol ISO 7000 -0790  (2004 -01). They shall also 
be marked with symbol IEC 60417- 6181  (2016- 01) and the model or type reference of the 
detachable power supply part  or with the substance of the following:  
Use only with <model or type reference> supply unit  
Class II appliances  and class III appliances  incorporating a functional earth shall be marked 
with the symbol IEC 60417- 5018 (2011- 07). 
The enclosure of electrically- operated water valves incorporated in external hose- sets for 
connection of an appliance to the water mains shall be marked with symbol 
IEC 60417 -5036  (2002- 10) if their working voltage exceeds extra- low voltage.  
Compliance is checked by inspection.  
7.2 Stationary appliances  for multiple supply shall be marked with the substance of the 
following:  
Warning: Before obtaining access to terminals, all supply circuits must be disconnected 
This warning shall be placed in the vicinity of the terminal cover.  
Compliance is checked by i nspection.  
7.3 Appliances having a range of rated values and which can be operated without adjustment 
throughout the range shall be marked with the lower and upper limits of the range separated by a hyphen.  
NOTE 1  Example: 115 V – 230 V: The appliance is suitable for any value within the marked range (a curling iron 
with a PTC heating element or an appliance incorporating an input switch mode power supply).  
Appliances having different rated values and which have to be adjusted for use at a particular value by the user or installer shall be marked with the different values separated by an oblique 
stroke.  This requirement is also applicable to appliances with provision for connection to both 
single -phase and multi -phase supplies.  
NOTE 2  Example: 115/230 V: The appliance is only suitable for the marked values (an appliance  with a selector 
switch).  
NOTE 3  Example: 230  V /400 V 3N : The appliance is only suitable for the voltage values indicated, 230 V  
being for single -phase, AC operation and 400 V 3N  for three- phase, AC with neutral  operation (an appliance with 
terminals for both supplies).  
Compliance is checked by inspection.  
7.4 If the appliance can be adjusted for different rated voltages or rated frequencies , the 
voltage or the frequency  to which the appli ance is adjusted shall be clearly discernible. If  
frequent changes in voltage setting or frequency setting are not required, this requirement is 
 – 34 – IEC 60335- 1:2020 ©  IEC 20 20        considered to be met if the rated voltage  or rated frequency  to which the appliance is to be 
adjusted can be determined from a wiring diagram fixed to the appliance.  
The wiring diagram may be on the inside of a cover that has to be removed to connect the 
supply conductors. It shall not be on a label loosely attached to the appliance.  
Compliance is checked by insp ection.  
7.5 For appliances marked with more than one rated voltage  or with one or more rated 
voltage ranges, the rated power input or rated current for each of these voltages or ranges 
shall be marked. However, if the difference between the limits of a rated voltage range  does 
not exceed 10 % of the arithmetic mean value of the range, the marking for rated power input  
or rated current may be related t o the arithmetic mean value  of the range.  
The upper and lower limits of the rated power input  or rated current shall be marked on the 
appliance so that the relation between input and voltage is clear.  
Compliance is checked by inspection.  
7.6 When symbols are u sed, they shall be as follows : 
 [symbol IEC 60417- 5031  
(2002- 10)] direct current  
 [symbol IEC 60417- 5032  
(2002- 10)] alternating current  
3  [symbol IEC 60417- 5032- 1 
(2002- 10)] three- phase alternating current  
3N  [symbol IEC 60417- 5032- 2 
(2002- 10)] three- phase alternating current with neutral  
   [symbol IEC 60417- 5016  
(2002- 10)] fuse- link 
NOTE 1 The current rating of the fuse link can be indicated in association with this symbol.  
 
  time-lag miniature fuse -link where X is the 
symbol for the time/current characteristic as given in IEC 60127  
 [symbol IEC 60417- 5019 
(2006- 08)] protective earth  
 [symbol IEC 60417- 5018 
(2011 -07)] functional earthing 
 [symbol IEC 60417- 5172 
(2003- 02)] class II equipment 
 [symbol IEC 60417- 5012 
(2002- 10)] Lamp 
NOTE 2  The rated wattage of the lamp can be indicated in association with this symbol.  
IEC 60335 -1:2020 © IEC 2020 – 35 –         
 [symbol ISO 7000 -0434 A 
(2004 -01)] Caution 
 [symbol ISO 7000 -0790 
(2004 -01)] read operator's manual  
 [symbol IEC 60417 -5021 
(2002 -10)] Equipotentiality  
 [symbol IEC 60417 -5036 
(2002-10)] dangerous voltage  
 [symbol IEC 60417 -5180 
(2003 -02)] Class III appliance 
 [symbol IEC 60417 -6181  
(2016 -01)] detachable power supply part  
The symbol for nature of supply shall be placed next to the marking for rated voltage. 
The symbol for class II appliances  shall be placed so that it will be obvious that it is a part of 
the technical information and is unlikely to be confused with any other marking.  
Units of physical quantities and their symbols shall be those of the international standardized 
system.  
Additi onal symbols are allowed provided that they do not give rise to misunderstanding.  
Symbols specified in IEC  60417 and ISO 7000 may be used.  
Compliance is checked by inspection.  
7.7 Appliances to be connected to more than two supply conductors and appliances for 
multiple supply shall have a connection diagram fixed to them, unless the correct mode of connection is obvious.  
The correct mode of connection for multi -phase appliances is considered to be obvious if the 
terminals for the supply conductors are 
– indicated by arrows pointing towards the terminals ; or 
– m arked in words.  
The connection diagram may be the wiring diagram referred to in 7.4. 
Compliance is check ed by inspection.  
7.8 Except for type Z attachment , terminals used for connection to the supply mains shall 
be indicated as follows:  
– terminals intended exclusively for the neutral conductor shall be indicated by the letter N;  
– protective earthing terminals shall be indicated by symbol IEC 60417 -5019 (2006 -08); 
– functional earthing terminals shall be indicated by symbol IEC 60417 -5018 (2011 -07). 
 – 36 – IEC 60335- 1:2020 ©  IEC 20 20        These indications shall not be placed on screws, removable washers or other parts which can 
be removed when conductors are being connected.  
Compliance is checked by inspection.  
7.9 Unless it  is obviously unnecessary, switches which may give rise to a hazard when 
operated shall be marked or placed so as to indicate clearly which part of the appliance they control. Indications used for this purpose shall, wherever practicable, be comprehensible  
without a knowledge of languages or national standards.  
Compliance is checked by inspection.  
7.10 The different positions of switches on stationary appliances  and the different positions 
of controls on all appliances shall be indicated by figures, letters or o ther visual means. This 
requirement also applies to switches which are part of a control.  
If figures are used for indicating the different positions, the off position  shall be indicated by 
the figure 0 and the position for a higher value, such as output, i nput, speed or cooling effect, 
shall be indicated by a higher figure.  
The figure 0 shall not be used for any other indication unless it is positioned and associated 
with other numbers so that it does not give rise to confusion with the indication of the of f 
position . The figure 0 may be used on a digital programming keyboard.  
Compliance is checked by inspection.  
7.11 Controls intended to be adjusted during installation or in normal use shall be provided 
with an indication for the direction of adjustment.  
NOTE  An indication of + and – is considered to be sufficient. 
Compliance is checked by inspection.  
7.12 Instructions shall be provided in hard copy form with the appliance so that the appliance 
can be used safely.  
Instructions may be marked on the appliance as long as they are visible in normal use.  
NOTE  If the instructions are marked on the appliance they are considered to be provided in hard copy form.  
If it is necessary to take precautions during user maintenance , appropriate details shall be 
given. 
The instructions shall state the substance of the following:  
This appliance is not intended for use by persons (including children) with reduced physical, sensory or mental capabilities, or lack of experience and knowledge, unless they have been 
given s upervision or instruction concerning use of the appliance by a person responsible for 
their safety.  
Children should be supervised to ensure that they do not play with the appliance.  
The instructions for appliances having a part of class III construction  supplied from a 
detachable power supply  part shall state that the appliance is only to be used with the power 
supply unit provided with the appliance.  
The instructions for class III ap pliances shall state that it must only be supplied at safety extra -
low voltage corresponding to the marking on the appliance. This instruction is not necessary IEC 60335- 1:2020 © IEC 2020 – 37 –          for battery -operated appliances  if the battery is a primary battery  or secondary battery 
charged outside of the appliance.  
For appliances intended for use at altitudes exceeding 2  000 m, the maximum altitude of use 
shall be stated.  
The instructions for appliances incorporating a functional earth shall state the substance of the 
following:  
This appliance incorporates an earth connection for functional purposes.  
For appliances intended to be connected to a supply for the purposes of recharging the battery , 
the instructions shall state the substance of the following : 
WARNING: Use only an external  supply with the following specifications: <voltage and 
nature of supply> <power / current of supply>  
For appliances intended to be supplied from a detachable power supply part  for the purposes 
of recharging the battery , the type reference of the detachabl e power supply part shall be 
stated along with the substance of the following:  
WARNING: Only use the supply unit provided with this appliance . 
For appliances intended for use with batteries that use metal -ion chemistries , the instructions 
shall state the normal temperature range for charging the battery . 
If the symbol for detachable power supply part is used, its meaning shall be explained.  
Compliance is checked by inspection.  
7.12.1  If it is necessary to take precautions during installation of the appliance, appropriate 
details shall be given.  
If an appliance is intended to be permanently connected to the water mains and not connected by a hose- set, this shall be stated.  
For appliances marked with different rated voltages or different rated frequenc ies (separated 
by a /), instructions shall be included to indicate to the user or installer what action must be taken to adjust the appliance for operation at the required rated voltage  or rated frequency . 
Compliance is checked by inspection.  
7.12.2  If a stationa ry appliance  is not fitted with a supply cord and a plug, or with other 
means for disconnection from the supply mains having a contact separation in all poles that 
provide full disconnection under overvoltage category III conditions, the instructions shall  state 
that means for disconnection must be incorporated in the fixed wiring in accordance with the 
wiring rules.  
Compliance is checked by inspection.  
7.12.3  If the insulation of the fixed wiring supplying an appliance for permanent connection to 
the supply mains  can come into contact with parts having temperature rise exceeding 50 K 
during the test of Clause 11, the instructions shall state that the fixed wiring insulation m ust be 
protected, for example, by insulating sleeving having an appropriate temperature rating.  
Compliance is checked by inspection and during the test of Clause  11.  – 38 – IEC 60335- 1:2020 ©  IEC 20 20        7.12.4  The instructions for built -in appliances shall include information with regard to the 
following:  
– dimensions of the space to be provided for the appliance;  
– dimensions and position of the means for supporting and fixing the appliance within this 
space;  
– minimum distances between the various parts of the appliance and the surrounding structure;  
– minimum dimensions of ventilating openings and their correct arrangement;  
– connection of the appliance to the supply mains and the interconnection of any separate components;  
– necessity to allow disconnection of the appliance from the supply after installation, unless the appliance incorporates a switch complying with 24.3 . The disconnection may be 
achieved by having the plug accessible or by incorporating a switch in the fixed wiring in accordance with the wiring rules.  
Compliance is checked by inspection.  
7.12.5  For appliances with type X attachment  having a specially prepared cord, the 
instructions shall contain the substance of the following:  
If the supply cord  is damaged, it must be replaced by a special cord or assembly available 
from the manufacturer or its service agent.  
For appliances with type Y attachment, the instructions shall contain the substance of the 
following : 
If the supply cord  is damaged, it must be replaced by the manufacturer, its service agent 
or similarly qualified persons in order to avoid a hazard.  
For appliances with type Z attachment , the instructions  shall contain the substance of the 
following : 
The supply cord cannot be replaced. If the cord is damaged, the appliance should be 
scrapped.  
If a cord set is required to be provided with the appliance according to Subclause 22.58 , the 
instructions shall contain the substance of the following:  
If the cord set is damaged, it must be replaced by a special cord set available from the manufacturer or its service agent.  
Comp liance is checked by inspection.  
7.12.6  If a non- self-resetting thermal cut -out is required in order to comply with this 
standard , then the instructions for appliances incorporating a non-self-resetting thermal cut -
out that is reset by disconnection of the supply mains shall contain the substance of the 
following:  
CAUTION:  In order to avoid a hazard due to inadvertent resetting of the thermal cut -out, 
this appliance must not be supplied through an external switching device, such 
as a timer, or connected to a circuit that is regularly switched on and off by the 
utility.  
Compliance is checked by inspection.  IEC 60335- 1:2020 © IEC 2020 – 39 –          7.12.7  The instructions for fixed appliances shall state how the appliance is to be fixed to its 
support. The method of fixing stated is not to depend on the use of adhesives since they are 
not considered to be a reliable fixing means.  
Compliance is checked by inspection.  
7.12.8  The instructions for appliances connected to the water mains shall state : 
– the maximum inlet water pressure, in pascals;  
– the minimum inlet water pr essure, in pascals, if this is necessary for the correct operation 
of the appliance.  
The instructions for appliances connected to the water mains by  detachable hose -sets  shall 
state that the new hose- sets supplied with the appliance are to be used and that old hose -sets 
should not be reused.  
Compliance is checked by inspection.  
7.12.9  For each language, the instructions specified in 7.12  and from 7.12.1  to 7.12.8 shall 
be in hard copy form and shall  appear together before any other instructions supplied with the 
appliance. Alternatively, these instructions may be supplied with the appliance separately from 
any functional use booklet. They may follow the description of the appliance that identifies par ts, 
or follow the drawings/sketches common to the languages of the instructions.  
In addition, instructions shall also be available in an alternative format such as on a website or 
on request from the us er in a format such as a DVD . 
Compliance is checked by  inspection.  
7.13 Instructions and other text required by this standard shall be written in an official 
language of the country in which the appliance is to be sold.  
Compliance is checked by inspection.  
7.14 The markings required by this standard shall be clearly le gible.  
The signal words WARNING, CAUTION, DANGER if in the Latin alphabet shall be in uppercase 
having a height not less than: 
– 3,5 mm for appliances normally used on the floor;  
– 2,0 mm for portable appliances with a printable surface of less than 10  cm2; and 
– 3,0 mm for other appliances.  
NOTE  A height of 3,5 mm is similar to Arial 14 pt, 3,0 mm is similar to 12 pt Arial and 2,0 mm is similar to 8 pt Arial. 
Other typefaces might differ in the pt value.  
Uppercase letter of the text explaining the signal word shall be no smaller than 1,6  mm, with 
other letters according to the font size of the uppercase letter.  
Countries that do not use the Latin alphabet need to specify the minimum size of the script to 
be used taking into account what is specified for the Latin alphabet.  
Unless contrasting colours are used, moulded in, engraved, or stamped markings shall be either raised above or have a depth below the surface of at least 0,25 mm.  – 40 – IEC 60335- 1:2020 ©  IEC 20 20        The markings required by this standard shall be durable. On containers that are likely to be 
cleaned frequently, the m arkings shall not be by means of paint or enamel, other than vitreous 
enamel . 
Compliance is checked by inspection , by measurement  and by rubbing the marking by hand for 
15 s with a piece of cloth soaked with water and again for 15  s with a piece of cloth soaked with 
petroleum spirit. The petroleum spirit to be used for the test is aliphatic solvent hexane.  
After all the tests of this standard, the marking shall be clearly legible. It shall not be easily 
possible to remo ve marking plates nor shall they show curling.  
7.15 The markings specified in 7.1 to 7.5 shall be on a main part of the appliance.  
Markings on the appliance shall be clearly discernible from the outside of the appliance but if 
necessary after removal of a cover. For portable appliances , it shall be possible to remove or 
open this cov er without the aid of a tool. 
For stationary appliances, at least the name or trademark or identification mark of the 
manufacturer or responsible vendor and the model or type reference shall be visible when the 
appliance is installed as in normal use. Thes e markings may be beneath a detachable cover . 
Other markings may be beneath a cover only if they are near to the terminals. For fixed 
appliances , this requirement applies after the appliance has been installed according to the 
instructions provided with the appliance.  
Indications for switches and controls shall be placed on or near these components. They shall 
not be placed on parts which can be positioned or repositioned in such a way that the marking 
is misleading.  
The symbol IEC 60417 -5018 (2011- 07) shall be placed next to the symbol IEC 60417- 5172 
(2003- 02) or the symbol IEC 60417 -5180 (2003- 02) as appropriate.  
The type reference of the detachable power supply part shall be placed next to symbol 
IEC 60417 -6181  (2016- 01). 
The marking of the outlet load  shall be on the appliance close to the appliance outlet or socket -
outlet.  
Compliance is checked by inspection.  
7.16 If compliance with this standard depends upon the operation of a replaceable thermal 
link or fuse link, the reference number or other means for identifying the link shall be marked 
at such a place that it is clearly visible when the appliance has been dismantled to the extent necessary for replacing the link.  
NOTE  Marking on the link is allowed as long as the marking is legible after the link has functioned.  
This requirement does not apply to links which can only be replaced together with a part of the appliance.  
Compliance is checked by inspection.  IEC 60335- 1:2020 © IEC 2020 – 41 –          8 Protection against access to live parts  
8.1 Appliances shall be construct ed and enclosed so that there is adequate protection 
against accidental contact with live parts.  
Compliance is checked by inspection and by the tests of 8.1.1  to 8.1.3 , as applicable, taking 
into account 8.1.4 and 8.1.5. 
8.1.1  The requirement of 8.1 applies for all positions of the appliance when it is operated as 
in normal use, and after the removal of detachable parts , unless otherwise specified.  
Test probe B and test probe 18 of IEC 61032 are applied with a force not exceeding 1  N, the  
appliance being in every possible position, except that appliances normally used on the floor  
and having a mass exceeding 40  kg are not tilted. Through openings, the test probe is applied  
to any depth that the probe will permit and is rotated or angled bef ore, during and after  insertion 
to any position. If the opening does not allow the entry of the probe, the force on the probe in 
the straight position is increased to 20 N when probe B is used or 10  N when probe  18 is used. 
If the probe then enters the opening, the test is repeated with the probe in the  angled position.  
During the tests with test probe B, all detachable parts  are removed except lamps located 
behind a detachable cover are not removed, provided that the appliance can be isolated from 
the supp ly mains by means of a plug or an all -pole switch. However, during insertion or removal 
of lamps which are located behind a detachable cover , protection against contact with live 
parts of the lamp cap shall be ensured.  
During the tests with test probe 18, the appliance shall be fully assembled as in normal use 
without any parts removed.  
Test probe 18 is not applied to appliances for commercial use unless they are intended to be installed in an area open to the public.  
It shall not be possible to touch live parts  or live parts protected only by lacquer, enamel, 
ordinary paper, cotton, oxide film, beads, or sealing compound except self- hardening resins, 
with the probe.  
8.1.2  Test probe 13 of IEC 61032 is applied with a force not exceeding 1 N through openings 
in class 0 appliances, class II appliances and class II constructions , except for those giving 
access to lamp caps and live parts  in socket -outlets.  
NOTE  Appliance outlets are not considered to be socket- outlets.  
The test probe is also applied through openings in earthed metal enclosures having a non-
conductive coating such as enamel or lacquer.  
It shall not be possible to touch live parts with the test probe.  
8.1.3  Instead of test probe B, test probe 18 and test probe 13, for  appliances other than 
those of class II, test probe 41 of IEC 61032  is applied with a force not exceeding 1 N to live 
parts  of visibly glowing heating elements, all poles of which can be disconnected by a single 
switching action. It is also applied to parts supporting such elements, provided that it is obvious 
from the outside of the appliance, without removing covers and similar parts, that these supporting parts are in contact with the element.  
It shall not be possible to touch these live parts. 
If a single switching action is obtained by a switching device, the switching device shall provide 
full disconnection and the  clearances for full disconnection specified in 20.3.3 of   – 42 – IEC 60335 -1:2020 ©  IEC 20 20        IEC 61058 -1:20 16 shall be obtained from Table 12 of IEC 61058 -1:2016  using the next higher 
step for rated impulse withstand voltage.  
For appliance s provided with a supply cord  and without a switching device in their supply 
circuit, a single switching action may be obtained by the withdrawal of the plug from a socket -
outlet . 
Compliance is checked by inspection and by manual test.  
8.1.4  An accessible part  is not considered to be live if : 
– the part is supplied at safety extra- low voltage , provided that  
• for AC, the peak value of the voltage does not exceed 42,4  V; 
• for DC, the voltage does not exceed 42,4 V; 
or 
– the part is separated from live p arts by protective impedance . 
If protective impedance  is used, the current between the part and the supply source shall not 
exceed 2 mA for DC, its peak value shall not exceed 0,7 mA for AC and  
– for voltages having a peak value over 42,4  V up to and including 450  V, the capacitance 
shall not exceed 0,1 µF; 
– for voltages having a peak value over 450 V up to and including 15  kV, the discharge shall 
not exceed 45  µC; 
– for voltages having a peak value over 15  kV, the energy in the discharge shall not exceed 
350 mJ. 
Compliance is checked by measurement, the appliance being supplied at rated voltage. 
Voltages and currents are measured between the relevant parts and each pole of the supply 
source. Discharges are measured immediately after the interruption of the supply. The quantity 
of electricity and energy in the discharge is measured using a resistor  having a nominal non -
inductive resistance of 2 000  Ω. 
The quantity of electricity is calculated from the sum of all areas recorded on the voltage/time 
graph without taking voltage polarity into account. Details of a suitable circuit for measuring the 
current are given in Figure 4 of IEC 60990:2016. 
8.1.5  Live parts of built -in appliances, fixed appliances and appliances delivered in 
separate units, shall be protected at least by basic insulation  before installation or assembly.  
Compliance is checked by inspection and by applying test probe B of IEC 61032 as specified 
in 8.1.1 . 
8.2 Class II appliances and class II constructions  shall be constructed and enclosed so 
that there is adequate protection against accidental contact with basic insulation  and metal 
parts separate d from live parts  by basic insulation  only.  
It shall only be possible to touch parts which are separated from live parts by double 
insulation or reinforced insulation . 
Compliance is checked by inspection and by applying the test probes specified in 8.1.1  in 
accordance with the conditions specified in 8.1.1 . IEC 60335- 1:2020 © IEC 2020 – 43 –          8.3 For a battery -operated appliance  where the battery  circuit has a functional earth 
connection or a supply connection, it shall only be possible to touch parts within a battery 
compartment  where:  
– in class I appliances , class 0I appliances  and class II appliances , they are separated 
from live parts by double insulation  or reinforced insulation ; 
– in class 0 appliances, they are separated from live parts by basic insulation ; 
– the battery  compartment is of class III construction . However, if the limits in 8.1.4  are 
exceeded , then basic insulation  is required in addition to supply at SELV . 
Compliance is checked by inspection and by applying the test probes specified in 8.1.1 in 
accordance with the conditions specified in 8.1.1 . 
9 Starting of motor -operated appliances 
NOTE  Requirements and tests are specified in part 2 when necessary.  
10 Power input and current  
10.1  If an appliance is marked with rated power input , the power i nput at normal operating 
temperature shall not deviate from the rated power input  by more than the deviation shown in 
Table 1. 
Table 1 – Power i nput deviation  
Type of appliance Rated power input  
W Deviation  
All appliances  ≤25 +20 % 
Heating appliances and 
combined appliances  >25 and ≤ 200 ±10 % 
>200 +5 % or 20 W 
(whichever is the 
greater)  
–10 % 
Motor -operated 
appliances  >25 and ≤ 300 +20 % 
>300 +15 % or 60 W 
(whichever is the 
greater)  
 
The deviation for motor- operated appliances  applies for combined appliances  if the power 
input of the motors is more than 50 % of the rated power input . The permissible deviations 
apply for both limits of the range for appliances marked with a rated voltage range having limits differing by more than 10 % of the arithmetic mean value of the range.  
In case of doubt, the power input of the motors may be measured separately . 
Compliance is checked by measurement when the power input has stabilized with : 
– all circuits which can operate simultaneously being in operation;  
– the appliance being supplied at rated voltage ; 
– the appliance being operated under normal operat ion. 
If the power input varies throughout the operating cycle and its maximum value exceeds twice  
its arithmetic mean value occurring during a representative period, then the power input is the 
maximum value of the power input that is exceeded for more than 10  % of the representative  – 44 – IEC 60335- 1:2020 ©  IEC 20 20        period if this value is greater than the arithmetic mean value. Otherwise the power input is taken 
as the arithmetic mean value.  
NOTE  Guidance on the measurement of power input concerning a representative period is given in informative 
Annex  S. 
The test is carried out at both the upper and lower limits of the ranges for appliances marked 
with one or more rated voltage ranges, unless the marking of the rated power input is related 
to the arithmetic mean value of the relevant voltage range, in which case the test is carried out at a voltage equal to the arithmetic mean value of that range.  
Appliance outlets accessible to the user and socket -outlets accessible to the user  that: 
– are incorporated in appliances connected to the supply mains; and  
– operate at rated voltage 
are not loaded during the test ; however , their contribution to the power input is considered to 
be the marked outlet load  per appliance outlet or socket -outlet.  
10.2  If an appliance is marked with rated current , the current at normal operating temperature 
shall not deviate from the rated current  by more than the deviation shown in Table 2. 
Table 2 – Current deviation 
Type of appliance Rated current  Deviation  
 A  
All appliances  ≤0,2 +20 % 
Heating appliances and   
combined appliances  >0,2 and  ≤ 1,0 ±10 % 
>1,0 +5 % or 0,10  A 
(whichever is the 
greater)  
–10 % 
Motor -operated 
appliances  >0,2 and  ≤ 1,5 +20 % 
>1,5 +15 % or 0,30  A 
(whichever is the 
greater)  
 
The deviation for motor- operated appliances  applies for combined appliances  if the current 
of the motors is more than 50 % of the rated current . The permissible deviations apply for both 
limits of the range for appliances marked with a rated voltage range having limits differing by 
more than 10  % of the arithmetic mean value of the range.  
In case of doubt, the current of the motors may be measured separately . 
Compliance is checked by measurement when the current has stabilized with : 
– all circuits which can operate simultaneously being in operation;  
– the appliance being supplied at rated voltage ; 
– the appliance being operated under normal operation. 
If the current varies throughout the operating cycle and its maximum value exceeds  twice  its 
arithmetic mean value  occurring during a representative period, then the current is the maximum 
value of the current that is exceeded for more than 10 % of the representative period if this 
value is greater than the arithmetic mean value. Otherwise the current is taken as the arithmetic 
mean value.  
NOTE  Guidance on the measurement of current concerning a representative period is given in informative Annex  S. IEC 60335- 1:2020 © IEC 2020 – 45 –          The test is carried out at both the upper and lower limits of the ranges for appliances marked 
with one or more rated voltage ranges , unless the marking of the rated current is related to 
the arithmetic  mean value of the relevant voltage range, in which ca se the test is carried out at 
a voltage equal to the arithmetic mean value of that range.  
Appliance outlets accessible to the user and socket -outlets accessible to the user  that: 
– are incorporated in appliances connected to the supply mains; and  
– operate at rated voltage 
are not loaded during the test ; however , their contribution to the current is considered to be the 
marked outlet load  per appliance outlet or socket -outlet.  
11 Heating  
11.1  Appliances and their surroundings shall not attain excessive temperatures in normal use.  
Compliance is checked by determining the temperature rise of the various parts under the 
conditions specified in 11.2  to 11.7. 
11.2  Hand- held appliances  are held in their normal position of use.  
Appliances with pins for insertion into socket -outlets are plugged into an appropriate wall -
mounted sock et-outlet.  
Built -in appliances are installed in accordance with the instructions.  
Other heating appliances and other combined appliances  are placed in a test corner as 
follows:  
– appliances normally placed on a floor or table in use are placed on the floor as near to the 
walls as possible;  
– appliances normally fixed to a wall are fixed to one of the walls, as near to the other wall 
and floor or ceiling as is likely to occur, taking into account the instructions;  
– appliances normally fixed to a ceiling are fixed to the ceiling as near to the walls as is likely to occur, taking into account in the instructions.  
Other motor -operated appliances  are positioned as follows:  
– appliances normally placed on a floor or table in use are placed on a horizontal support;  
– appliances normally fixed to a wall are fixed to a vertical support;  
– appliances normally fixed to a ceiling are fixed underneath a horizontal support.  
Dull black -painted plywood approximately 20  mm thick is used for the test corner, the supports 
and for t he installation of built -in appliances . 
For appliances provided with an automatic cord reel, one- third of the total length of the cord is 
unreeled. The temperature rise of the cord sheath is determined as near as possible to the hub 
of the reel and also between the two outermost layers of the cord on the reel.  
For cord storage devices, other than automatic cord reels, which are intended to accommodate the supply cord partially while the appliance is in operation, 50  cm of the cord is unwound. The 
temperatur e rise of the stored part of the cord is determined at the most unfavourable place.   – 46 – IEC 60335- 1:2020 ©  IEC 20 20        11.3  Temperature rises, other than those of windings, are determined by means of 
thermocouples having a diameter not exceeding 0,3  mm positioned so that they have minimum 
effect on the temperature of the part under test.  
Thermocouples used for determining the temperature rise of the surface of walls, ceiling and 
floor of the test corner are attached to the back of small blackened disks of copper or brass, 
15 mm in diameter and 1 mm thick. The front of the disk is flush with the surface of the board.  
As far as is possible, the appliance is positioned so that the thermocouples detect the highest temperatures.  
If it is necessary to dismantle the appliance to position thermocouples, v erify that the appliance 
has been correctly reassembled. In case of doubt, remeasure the power input or input current as appropriate.  
The temperature rise of electrical insulation, other than that of windings, is determined on the surface of the insulation  at places where failure could cause : 
– a short circuit;  
– contact between live parts  and accessible metal parts ; 
– bridging of insulation;  
– a reduction of clearances or creepage distances below the values specified in Clause  29. 
NOTE  1 The point of separation of the cores of a multicore cord and the point where insulated wires enter 
lampholders are examples of places where thermocouples are positioned.  
Temperature rises of windings are determined by the resistance method unless the windings are non -uniform or if it is difficult to make the necessary connections, in which case the 
temperature rise is d etermined by means of thermocouples. At the beginning of the test, the 
windings are to be at room temperature . 
The temperature rise of a winding is calculated from the formula:  
Δt = 
11 2
RR R− (k + t1) – (t2 – t1) 
where  
Δt is the temperature rise of the winding;  
R1 is the resistance at the beginning of the test;  
R2 is the resistance at the end of the test;  
k is equal to 
• 225 for aluminium windings and copper/aluminium windings with an aluminium content 
≥ 85 %,  
• 229,75 for copper/aluminium windings with an copper content > 15 % to < 85 %, 
• 234,5 for copper windings and copper/aluminium windings with an copper content  
≥ 85 %;  
t1 is room temperature  at the beginning of the test;  
t2 is room temperature  at the end of the test.  
NOTE 2 T he resistance of windings at the end of the test can be determined by taking resistance measurements 
as soon as possible after switching off and then at short intervals so that a curve of resistance against time can be 
plotted for ascertaining the resistance at the instant of switching off.  IEC 60335- 1:2020 © IEC 2020 – 47 –          11.4  Heating appliances  are operated under normal operation  and at 1,15 times rated 
power input . 
11.5  Motor- operated appliances are operated under normal operation and supplied with 
the most unfavourable voltage between 0,94 times and 1,06 times the rated voltage.  
11.6  Combined appliances  are operated under normal operation and supplied with the most 
unfavourable voltage between 0,94 times and 1,06 times the rated voltage.  
11.7  The appliance is operated for a duration corresponding to the most unfavourable 
conditions of normal use.  
Appliance outlets accessible to the user and socket -outlets accessible to the user are loaded 
with a resistive load that gives the marked outlet load . 
For appliances incorporating integral batteries or separable batteries not disconnected from 
the appliance for charging purposes : 
– the battery that has been fully discharged is charged for 1  h, while the appliance is 
operated continuously performing its intended function , if allowed by the construction of the 
appliance ; 
– the battery  that has been fully discharged is charged, for a duration of 24 h or until it is 
fully charged  whichever is shorter, without the battery- operated appliance  performing its 
intended function.  
NOTE  The duration of the test can consist of more than one cycle of operation.  
11.8  During the test, the temperature rises are monitored continuously and shall not exceed 
the values shown in Table 3. 
If the temperature rise of the motor winding exceeds the value specified in Table 3 or if there is 
doubt with regard to the temperature classification of the insulation of the motor, the tests of 
normative Annex  C are carried out.  
Protective devices shall not operate and sealing compound shall not flow out. However, 
components in protective electronic circuits are allowed to operate provided they are tested 
for the number of cycles of ope ration specified in 24.1.4. 
Table 3 – Maximum normal temperature rises 
Part  Temperature rise  
 K 
Windings a, if the winding insulation according to IEC 60085 is:    
– class 105 (A)  75 (65) 
– class 120 (E)  90 (80) 
– class 130 (B)  95 (85) 
– class 155 (F)  115  
– class 180 (H)  140  
– class 200 (N)  160  
– class 220 (R)  180  
– class 250  210  
Pins of appliance inlets:    
– for very hot conditions  130  
– for hot conditions  95  
– for cold conditions  45   – 48 – IEC 60335- 1:2020 ©  IEC 20 20        Part  Temperature rise  
 K 
Pins of appliances for insertion into socket- outlets , pins of plug connectors inserted into 
appliance outlets accessible to the user and plugs inserted into socket- outlets accessible 
to the user  45  
Terminals, including earthing terminals  and functional earthing terminals , for external 
conductors of stationary appliances, unless they are provided with a supply cord  60  
Ambient of switches, thermostats  and temperature limiters : b   
– without T -marking 30  
– with T -marking  T-25  
Rubber, polychloroprene or polyvinyl chloride insulation of internal and external wiring, 
including supply cords:   
– without temperature rating or with a temperature rating not exceeding 75 °C  50  
– with temperature rating (T)  j where T exceeds 75  °C T-25  
Cord sheaths used as supplementary insulation  35  
Sliding contacts of cord reels  65  
Points where the insulation of wires can come into contact with parts of a terminal block or compartment for fixed wiring, for a stationary appliance  not provided with a supply cord . 50 c  
Rubber, other than synthetic, used for gaskets or other parts, the deterioration of which 
could affect safety:    
– when used as supplementary insulation  or as  reinforced insulation  40  
– in other cases  50  
Lampholders with T -marking  d   
– B15 and B22 marked T1  140  
– B15 and B22 marked T2  185  
– other lampholders  T-25  
Lampholders without T -marking d   
– E14 and B15  110  
– B22, E26 and E27  140  
– other  lampholders and starter holders for fluorescent lamps  55  IEC 60335- 1:2020 © IEC 2020 – 49 –          Part  Temperature rise  
 K 
Material used as insulation, other than that specified for wires and windings : e   
– impregnated or varnished textile, paper or press -board  70  
– laminates bonded with:    
 • melamine- formaldehyde, phenol -formaldehyde or phenol -furfural resins  85 (175)  
 • urea- formaldehyde resin  65 (150)  
– printed circuit boards bonded with epoxy resin  120  
– moulding of:    
 • phenol -formaldehyde with cellulose fillers  85 (175)  
 • phenol -formaldehyde with mineral fillers  100 (200)  
 • melamine- formaldehyde  75 (150)  
 • urea- formaldehyde  65 (150)  
– polyester with glass reinforcement  110  
– silicone rubber  145  
– polytetrafluoroethylene  265  
– pure mica and tightly sintered ceramic material when such materials are used as 
supplementary insulation  or reinforced insulation  400  
– thermoplastic material  f –  
Wood, in general g 65  
– Wooden supports, walls, ceiling and floor of the test corner and wooden cabinet:    
 • stationary appliances liable to be operated continuously for long periods  60  
 • other appliances  65  
Outer surface of capacitors: h   
– with marking of maximum operating temperature (T): i T-25  
– without marking of maximum operating temperature:    
 • small ceramic capacitors for radio and television interference suppression  50  
 • capacitors complying with IEC 60384- 14:2013 including IEC  60384- 14:2013/AMD1:2016  50  
 • other capacitors  20  
External enclosure of motor -operated appliances except handles held in normal use:m   
– of bare metal  48  
– of coated metaln 59  
– of glass and ceramic  65  
– of plastic having a thickness exceeding 0,4  mml 74  
Surfaces of handles, knobs, grips and similar parts which are continuously held in normal 
use (e.g. soldering irons):m   
– of bare metal  30  
– of coated metaln 34  
– of porcelain or vitreous material  40  
– of rubber or of plastic having a thickness exceeding 0,4  mml 50  
– of wood  50   – 50 – IEC 60335- 1:2020 ©  IEC 20 20        Part  Temperature rise  
 K 
Surfaces of handles, knobs, grips and similar partsk which are held for short periods only 
in normal use (e.g. switches):m   
– of bare metal  35  
– of coated metaln 39  
– of porcelain or vitreous material  45  
– of rubber or of plastic having a thickness exceeding 0,4  mml 60  
– of wood  65  
Parts in contact with oil having a flash- point of t °C t-50  
NOTE 1  If other materials than those mentioned in the table are used, they are not to be subjected to 
temperatures in excess of their thermal capabilities as determined by ageing tests.  
NOTE 2  The values in the table are based on an ambient temperature not normally exceeding 25 °C but 
occasionally reaching 35 °C. However, the temperature rise values specified are based on 25 °C. 
NOTE 3  The temperature of the terminals of switches is measured if the switch is tested in accordance with 
normative Annex  H. 
 
a To allow for the fact that the average temperature of windings of universal motors, relays, solenoids and similar 
components is usually above the temperature at the points on the windings where thermocouples are placed, 
the figures without parentheses apply when the resistance method is used and those within parentheses apply 
when thermocouples are used. For windings of vibrator coils and AC motors, the figures without parentheses apply in both cases.  
 The temperature rise limit of windings in transformers and inductors mounted on printed circuit boards is equal to the thermal class of the winding insulation reduced by 25 K provided the largest dimension of the winding 
does not exceed 5 mm in cross section or length.  
 For motors constructed so that the circulation of air between the inside and the outside of the case is prevented but which are not necessarily sufficiently enclosed to be considered airtight, the temperature rise limits may be increased by 5 K. 
 For hermetically sealed motors, the temperature rise limit may be increased by 8 K. 
b T means the maximum ambient temperature in which the component or its switch head can operate.  
 The ambient is the temperature of the air at the hottest point at a distance of 5 mm from the surface of the component concerned. However, if a thermostat or a temperature limiter  is mounted on a heat- conducting 
part, the declared temperature limit of the mounting surface (Ts) is also applicable. Therefore, the temperature rise of the mounting surface has to be measured.  
 T he temperature rise limit does not apply to switches or controls tested in accordance with the conditions 
occurring in the appliance.  
c This limit may be exceeded if the instruction specified in 7.12.3 is supplied . 
d Locations for measuring the temperature rises are specified in Table 12.1  of IEC  60598- 1:2014 including 
IEC 60598- 1:2014/AMD1:2017. 
e The values in parentheses apply to locations where the part is fixed to a hot surface.  
f There is no specific limit for thermoplastic material. However, the temperature rise has to be determined in order that the tests of 30.1 can be carried out.  
g The limit specified concerns the deterioration of wood and it does not take into account deterioration of surface finishes.  
h There is no limit for the temperature rise of capacitors that are short- circuited in 19.11. 
i Temperature marking for capacitors mounted on printed circuit boards may be given in the technical sheet.  
j IEC 60245 Types 53 and 57 supply cords have a T rating of 60 °C; 
 IEC 60245 Type 88 supply cords have a T rating of 70 °C; 
 IEC 60227 Types 52 and 53 supply cords have a T rating of 70 °C; 
 IEC 60227 Types 56 and 57 supply cords have a T rating of 90 °C; 
 IEC 62821 Types 101 and 101f supply co rds have a T rating of 70 °C; 
 IEC 62821 Types 102 and 102f supply cords  have a T rating of 70 °C. IEC 60335- 1:2020 © IEC 2020 – 51 –          k The temperature rise limits of controls actuated by contact or proximity of a finger, with no movement of the 
contact surface also includes all surfaces within 5  mm of such controls, regardless of their shape.  
l The temperature rise limit of plastic also applies for plastic material having a metal finish of thickness less than 0,1 mm.  
m When the thickness of the plastic coating does not exceed 0,4 mm, the temperature rise limits of the coated 
metal or of glass and ceramic material apply.  
n Metal is considered coated when a coating having a minimum thickness of 90 µm made by enamel, powder or 
non- substantially plastic coating is used. 
 
12 Charging of metal -ion batter ies 
Charging a batter y that uses metal -ion chemistry  under normal operation shall not cause any 
cell to exceed its specified operating region for charging . 
Compliance is checked using a battery that has been  fully discharged, by charging the battery, 
with the charging system  indicated in the instructions, at an ambient temperature of 
20 °C ± 5 °C, irrespective of the minimum and maximum ambient temperatures for charging  the 
battery  specified in the instructions.  
If the manufacturer’s specified : 
– minimum ambient temperature for charging the battery is less than 10  °C, the test is 
repeated at the specified minimum ambient temperature  +
−05 °C; 
– maximum ambient tempe rature for charging the battery is greater than 40 °C, the test is 
repeated at the specified maximum ambient temperature   +
−50 °C. 
For all individual  cells , the voltage, the temperature and the charging current are monitored.  
In the case of parallel configurations, analysis may be used to avoid measuring the individual branch currents. The result shall not exceed the specified operating region for charging  (e.g. 
limits of voltage and current dependent on the temperature).  
NOTE 1 The following are example results of such analysis:  
The charging current for each branch of a parallel connection would not need to be monitored, if: 
– the maximum deliverable current of the charging system  did not exceed the maximum charging current of a 
single cell; or  
– for cells with identical specifications, the maximum deliverable current of the charging system  divided by the 
number of branches of parallel connections does not exceed the maximum charging current of a single cell. 
Currents measured during battery  charging shall be the average current over a period of between 1  s and 5  s. 
The location of thermocouples for each cell temperature measurement shall be on the outer 
surface, halfway  along the longest dimension of the cell. 
NOTE 2  A specially prepared battery  can be used for this test.  
For each cell, the specified operating region for charging  specified by the cell manufacturer 
shall not be exceeded at the temperature of the cell (Tcell). 
When the test is carried out at an ambient temperature of 20 °C ± 5 °C 
– Tcell = Tmeas  + (Tamb(max)  – Tamb(test) ), for the maximum recommended ambient temperature 
for charging ; 
– Tcell = Tmeas  – (Tamb(test)  – Tamb(min) ), for the minimum recommended ambient temperature 
for charging .  – 52 – IEC 60335- 1:2020 ©  IEC 20 20        When the test is carried out at the recommended ambient temperature for charging, Tcell = 
Tmeas  
where  
Tmeas   is the  cell surface temperature measured during the test; 
Tcell  is the cell surface temperature specified by the cell manufacturer ; 
Tamb(max)   is the m aximum ambient temperature  for charging specified by the 
manufacturer ; 
Tamb(min)   is the minimum ambient temperature  for charging specified by the 
manufacturer ; 
Tamb(test)   is the ambient temperature of the test room during the test . 
For batteries where the cells are configured in series, the test is repeated with the charge in 
one battery deliberately imbalanced. The imbalance is introduced into a battery  that is fully 
discharged  by charging one cell to approximately 50 % of being fully charged . 
If it can be demonstrated that an imbalance less than 50  % would actually occur in normal 
operation , then this lower imbalance may be used.  
This may be demonstrated by operating the battery  in cycles. Each cycle starts with the battery  
fully discharged  then the battery  is fully charged . The cycling is continued until the battery  
capacity has decreased to 80  % of its rated capacity. The imbalance at this decreased capacity 
is then used.  
Use of a lower imbalance may also be demonstrated through evaluation of those designs that 
employ circuitry intended for maintaining balance between cells  in the battery . Batteries with 
a small number of cells  in series may be shown to exhibit limited imbalance in practice, if 
charging ceases with the battery  prepared with a s maller initial imbalance. 
13 Leakage current and electric strength at operating temperature  
13.1  At operating temperature, the leakage current of the appliance shall not be excessive 
and its electric strength shall be adequate.  
Compliance is checked by the tests of 13.2 and 13.3 . 
The appliance is operated under normal operation for the duration specified in 11.7. 
Heating appliances  are operated at 1,15 times the rated power input . 
Motor- operated appliances and combined appliances  are supplied at 1,06 times rated 
voltage. 
Three- phas e appliances, which according to the instructions for installation are also suitable 
for single -phase supply, are tested as single- phase appliances with the three circuits connected 
in parallel.  
Protective impedance and radio interference filters are disconnected before carrying out the 
tests.  
13.2  The leakage current is measured by means of the circuit described in Figure 4 of 
IEC 60990: 2016 . For class 0I appliances and class I appliances, except parts of class II IEC 60335- 1:2020 © IEC 2020 – 53 –          construction , C may be replaced by a low impedance ammeter responding to the rated 
frequency of the  appliance.  
The leakage current is measured between any pole of the supply and: 
– accessible metal parts intended to be connected to protective earth, for class l appliances 
and class 0l appliances ; 
– metal foil having an area not exceeding 20  cm × 10 cm which is in contact with accessible 
surfaces  of insulating materials  and metal parts not intended to be connected to protective 
earth , for class 0 appliances, class II appliances, class ll constructions and class III 
appliances . 
The metal foil has the largest area possible on the surface under test without exceeding the 
dimensions specified. If its area is smaller than the surface under test, it is moved to test all 
parts of the surface. The heat dissipation of the appliance is not to be affected by the metal foil.  
For single -phase appliances, the measuring circuit is shown in the following figures:  
– if they are class II appliances or parts of class II  construction, Figure 1; 
– if they are neither class II appliances nor parts of  class II  construction , Figure 2. 
The leakage current is measured with the selector switch in each of the positions a and b.  
For three- phase with neutral (3N~) connected appliances, the measuring circuit is shown in the 
following figures:  
– if they are class II appliances or parts of class II construction , Figure 3; 
– if they are neither class II appliances nor parts of class II construction , Figure 4. 
The leakage current is measured with the switches a, b and c in the closed position. The 
measurements are then repeated with each of the switches a, b and c open in turn, the other two switches remaining closed. For three- phase without neutral (3~) connecte d appliances, the 
measuring circuit in Figure 3 or Figure 4 shall be used as applicable, but the neutral is not 
connected  to the appliance . 
After the appliance has been operated for a duration as specified in 11.7 , the leakage current 
shall not exceed the following values:  
– for class II appliances and for parts  0,35  mA peak  
of class II construction  
– for class 0 and class III appliances  0,7 mA peak  
– for class 0I appliances  0,5 mA 
– for portable class I appliances 0,75  mA 
– for stationary class I motor -operated appliances  3,5 mA 
– for stationary class I heating appliances 0,75  mA or 0,75  mA per kW rated 
 power input  of the appliance with a 
 maximum of 5  mA, whichever is 
 higher  
For combined appliances , the total leakage current may be within the limits specified for 
heating appliances or motor -operated appliances , whichever is the greater, but the two limits 
are not added.  
If the appliance incorporates capacitors and is provided with a single- pole swit ch, the 
measurements are repeated with the switch in the off position .  – 54 – IEC 60335- 1:2020 ©  IEC 20 20        If the appliance incorporates a thermal control which operates during the test of Clause  11, the 
leakage current is measured immediately before the control opens the circuit . 
NOTE  The test with the switch in the off position is carried out to verify that capacitors connected behind a single-
pole switch do not cause an excessive leakage current.  
WARNING – In order to avoid an electric shock hazard, the appliance shall be supplied through 
an isolating transformer or it shall be insulated from earth.  
13.3  The appliance is disconnected from the supply and the insulation is immediately 
subjected to a voltage having a frequency of 50 Hz or 60  Hz for 1 min, in accordance with 
IEC 61180.  
The high -voltage source used for the test is to be capable of supplying a short circuit current Is 
between the output terminals after the output voltage has been adjusted to the appropriate test 
voltage. The overload release of the circuit is not to be operated by any current below the tripping current I
r. The values of Is and Ir are given in Table 5 for various high- voltage sources.  
The test voltage is applied between live parts  and accessible parts , non -metallic parts being 
covered with metal foil. For class II constructions  having intermediate metal between live 
parts  and accessible parts , the voltage is applied across the basic insulation  and the 
supplementary insulation . 
During the test , care shall be taken to avoid overstressing the components of electronic 
circuits. 
The values of the test voltages are specified in Table 4. 
Table 4 – Voltage for electric strength test  
Insulation  Test voltage  
V 
Rated voltage a Working voltage (U)  
SELV  ≤150 V >150 V and ≤250 V b >250 V 
Basic insulation  500 1 000  1 000  1,2 U + 700  
Supplementary insulation   1 250  1 750  1,2 U + 1 450  
Reinforced insulation   2 500  3 000  2,4 U + 2 400  
a  For multi -phase appliances, the line to neutral or line to earth voltage is used for rated voltage. The test 
voltage for 480 V multi -phase appliances is that specified for a rated voltage in the range > 150 V and ≤ 
250 V. 
b For appliances having a rated voltage  ≤ 150 V, these test voltages apply to parts having a working 
voltage > 150 V ≤ 250 V. 
 
No breakdown shall occur during the test.  
Glow discharges without a drop in voltage are neglected.  
Table 5 – Characteristics of high -voltage sources  
Test voltage  Minimum current  
mA 
V Is Ir 
 ≤ 4 000  200 100 IEC 60335- 1:2020 © IEC 2020 – 55 –           >  4 000 and ≤ 10 000  80 40 
 >  10 000 and ≤ 20 000  40 20 
NOTE  The currents are calculated on the basis of the short circuit and release 
energies of 800  VA and 400 VA respectively at the upper end of the voltage ranges.  
 
14 Transient overvoltages  
Appliances shall withstand the transient over- voltages to which they may be subjected.  
Compliance is checked by subjecting each clearance  having a value less than those specified 
in Table 16 to an impulse voltage test.  
The impulse test voltage has a no- load wave shape corresponding to the 1,2/50 µ s standard 
impulse specified in IEC 61180. The impulse test voltage is applied three times for each polarity 
with intervals of at least 1 s. 
The impulse test voltage is specified in  Table 6 for rated impulse voltages given in Table 15. 
Table 6 – Impulse test voltage  
Rated impulse voltage  Impulse test voltagea 
V V 
330 357 
500 540 
800 930 
1 500  1 750  
2 500  2 920  
4 000  4 920  
6 000  7 380  
8 000  9 840  
10 000  12 300  
a The impulse test voltages have been calculated using correction factors for 
testing at locations situated at sea level. It is considered that they are appropriate for any location between sea level and 500  m. If tests are carried out at other 
locations, other correction factors shall  
be used as noted in  
Subclause 6.1.2.2.1.3 of IEC 60664-1 :2007. 
 
There shall be no flashover. However, flashover of functional insulation is allowed if the 
appliance complies with Clause  19 when the clearance  is short -circuited.  
15 Moisture resistance  
15.1  The enclosure of the appliance shall provide the degree of protection against moisture in 
accordance with the classification of the appliance.  
Compliance is checked as specified in 15.1.1  taking into account 15.1.2, the appliance not being 
connected to the supply mains.  
The appliance shall then withstand the electric strength test of 16.3 and, after carefully wiping 
the external enclosure to remove any surplus water,  an inspection shall show that there is no  – 56 – IEC 60335- 1:2020 ©  IEC 20 20        trace of water on insulation which could result in a reduction of clearances  or creepage 
distances below the values specified in Clause  29. For appliances and parts of appliances with 
pins for insertion into socket -outlets an inspection shall show that no water has entered the 
enclosure.  
15.1.1  Appliances other than those classified IPX0 are subjected to the tests of 
IEC 60529:1989 including IEC 60529:1989/AMD1:199 9 and IEC 60529:1989/AMD2:2013.  
IPX3 appliances are tested as described in Subclause 14.2.3a). The test as described in 
subclause 14.2.3b) may be used for testing appliances that cannot be placed under the 
oscillating tube.  
IPX4 appliances are tested as described in Subclause 14.2.4a).  The test as described in 
subclause 14.2.4 b) may be used for testing appliances that cannot be placed under the 
oscillating tube;  
IPX7 appliances are tested as described in Subclause 14.2.7. For this test, the appliance is immersed in water containing approximately 1  % NaCl.  
Water valves containing live parts and that are incorporated in external hoses for connection 
of an appliance to the water mains are subjected to the test specified for IPX7 appliances.  
15.1.2  Hand- held appliances are turned continuously through the most unfavourable 
positions during the test.  
Appliances with an automatic cord reel are tested to 15.1.1  with the supply cord  unreeled and 
coiled in close proximity to the appliance under test so that the minimum diameter of the coil is 30 cm. The coil is concentric and in a single layer positioned in such a way that the appliance 
and the supply cord  are subjected to water spray. After the test of 15.1.1  is completed, the 
supply cord shall be reeled into the appliance at free speed. The supply cord shall not be 
dried before reeling.  
If the appliance is a fixed appliance mounted on the wall or ceiling, the cord will be allowed to 
drop to the floor from a height equal to the minimum hei ght specified in the instructions before 
being coiled.  
Built -in appliances are installed in accordance with the instructions.  
Appliances normally used on the floor or table are placed on a horizontal unperforated support having a diameter of twice the oscillating tube radius minus 15  cm. 
Appliances normally fixed to a wall are mounted as in normal use in the centre of a wooden 
board having dimensions which are 15  cm 
± 5 cm in excess of those of the orthogonal 
projection of the appliance on the board. The wooden board is placed at the centre of the 
oscillating tube.  
Appliances and part s of appliances with integral pins for insertion into socket -outlets are held 
by the pins in the most unfavourable position during the test. They are not mounted in a socket -
outlet for the tests. They may be held by the pins using a laboratory clamp or similar device.  
For IPX3 appliances, the base of wall -mounted appliances is placed at the same level as the 
pivot axis of the oscillating tube.  
For IPX4 appliances, the horizontal centre line of the appliance is aligned with the pivot axis of 
the oscillating tube. However, for appliances normally used on the floor or table, the movement is limited to two times 90° from the vertical for a period of 5  min, the support being placed at 
the level of the pivot axis of the oscillating tube.  IEC 60335- 1:2020 © IEC 2020 – 57 –          If the instructions for wall -mounted appliances state that the appliance is to be placed close to 
the floor level and specifies a distance, a board is placed under the appliance at that distance. 
The dimensions of the board are 15 cm more than the horizontal projection of the appliance.  
Appliances normally fixed to a ceiling are mounted underneath a horizontal unperforated 
support that is constructed to prevent water spraying onto its top  surface. The pivot axis of the 
oscillating tube is located at the same level as the underside of the support and aligned centrally with the appliance. The spray is directed upwards. For IPX4 appliances, the movement of the 
tube is limited to two times 90º  from the vertical for a period of 5 min.
 
Appliances with type X attachment, except those having a specially prepared cord, are fitted 
with the lightest permissible type of flexible cord of the smallest cross -sectional area specified 
in Table 13. 
Detachable parts are removed and subjected, if necessary, to the relevant treatment with the 
main part. However, if the instructions state that a part has to be removed for user maintenance 
and a tool is needed, this part is not removed.  
15.2  Appliances subject to spillage of liquid in normal use shall be constructed so that such 
spillage does not affect their electrical insulation.  
Compliance is checked by the followi ng test  using a spillage solution comprising water 
containing approximately 1 % NaCl and 0,6 % rinsing agent . 
Appliances with type X attachment, except those having a specially prepared cord, are fitted 
with the lightest permissible type of flexible cord of the smallest cross -sectional area specified 
in Table 13. 
Appliances incorporating an appliance inlet are tested with or without an appropriate connector in position, whichever is most unfavourable.  
Detachable parts are removed.  
The liquid container of the appliance is completely filled with the solution and a further quantity 
equal to 15  % of the capacity of the container or 0,25 l, whichever is the greater, is poured in 
steadily over a period of 1 min.  
Any commercially available  non-ionic  rinsing agent may be used, but if there is any doubt with 
regards to the test results, the rinsing agent shall have the following properties:  
– viscosity, 17 mPa  s; 
– pH, 2,2 (1 % in water) ; 
– and its composition shall comprise the following substances  
– Plurafac ® LF 221
11  15,0 %  parts by mass  
– Cumene sulfonate (40 % solution)  11,5 %  parts by mass  
– Citric acid (anhydrous) 3,0 % parts by mass  
– Deionized water  70,5 %  parts by mass  
The appliance shall then withstand the electric strength test of  16.3 and inspection shall show 
that there is no trace of water on insulation that could result in a reduction of clearances or 
creepage distances below the values sp ecified in  Clause 29. 
___________ 
11 Plurafac ® LF 221 is the trade name of a product supplied by BASF. This information is given for the convenience 
of users of this document and does not constitute an endorsement by IEC of this product .  – 58 – IEC 60335- 1:2020 ©  IEC 20 20        15.3  Appliances shall be proof against humid conditions that may occur in normal use.  
Compliance is checked by test Cab: Damp heat steady state in IEC 60068 -2-78 under the 
following conditions.  
Appliances that were subjected to the tests of 15.1 or 15.2  are placed in normal ambient 
conditions for 24  h. 
Cable entries, if any, are left open. If knock -outs are provided, one of them is opened.  
Detachable parts are removed and subjected, if necessary, to the humidity test with the main 
part.  
The humidity test is carried out for 48  h in a humidity cabinet containing air with a relative 
humidity of (93 ± 3) %. The temperature of the air is maintained within 2 K of any convenient 
value t between 20 °C and 30  °C. Before being placed  in the humidity cabinet, the appliance is 
brought to a temperature of t4
0+ °C. 
If it is not possible to place the whole appliance in the humidity cabinet, parts containing 
electrical insulation may be tested separately, taking into account the conditions that the electrical insulation is subjected to within the appliance.  
The appliance shall then withstand the tests of Clause  16 in the humidity cabinet or in the room 
in which the appliance was brought to the prescribed temperature after reassembly of those parts that may have been removed.  
16 Leakage current and electric strength  
16.1  The leakage current of the appliance shall not be exc essive and its electric strength shall 
be adequate.  
Compliance is checked by the tests of 16.2 and 16.3 .  
Protective impedance is disconnected from live parts  before carrying out the tests.  
The tests are carried out on the appliance at room temperature and not connected to the supply 
mains.  
16.2  An AC test voltage is applied between live parts  and: 
– accessible metal parts intended to be connected to protective earth, for class l appliances 
and class 0l appliances ; 
– metal foil having an area not exceeding 20 cm × 10 cm which is in contact with accessible 
surfaces  of insulating material and metal parts not intended to be connected to protective 
earth, for class 0 appliances, class II appliances, class ll constructions and class III 
appliances . 
The test voltage is : 
– 1,06 times rated voltage , for single -phase appliances;  
– 1,06 times rated voltage , divided by 3, for three -phase appliances.  
The leakage current is measured within 5  s after the application of the test voltage.  
The leakage current shall not exceed the following values:  IEC 60335- 1:2020 © IEC 2020 – 59 –          – for class II appliances and for parts  0,25  mA 
of class II construction   
– for class 0, class 0I and class III appliances 0,5 mA 
– for portable class I appliances 0,75  mA 
– for stationary class I motor -operated appliances  3,5 mA 
– for stationary class I heating appliances 0,75  mA or 0,75  mA per kW rated 
 power input  of the appliance with a 
 maximum of 5  mA, whichever is 
 higher  
The values specified above are doubled if all controls have an off position in all poles. They 
are also doubled if : 
– the appliance has no control other than a thermal cut -out; or 
– all thermostats, temperature limiters  and energy regulators do not have an off position ; 
or 
– the appliance has radio interference filters. In this case, the leakage current with the filter 
disconnected shall not exceed the limits specified.  
For combined appliances , the total leakage current may be within the limits specified for 
heating appliances or motor -operated appliances , whichever is the greater, but the two limits 
are not added. 
For measuring the leakage current, a low impedance ammeter capable of measuring the true 
RMS  value of current may be used.  
16.3  Immediately after the test of 16.2, the i nsulation is subjected to a voltage having a 
frequency of 50 Hz or 60  Hz for 1 min in accordance with IEC 61180. The values of the test 
voltage for different types of insulation are given in Table 7. 
Accessible parts of insulating material are covered with metal foil.  Care is to be taken that the 
metal foil is placed so that no flashover occurs at the edges of the insulation.  
Table 7 – Test voltages  
Insulation  Test voltage  
V 
Rated voltage a Working voltage (U)  
SELV  ≤150 V  >150 V and ≤250 V b >250 V  
Basic insulation c 500 1 250  1 250  1,2 U + 950  
Supplementary insulation c – 1 250  1 750  1,2 U +  1 450  
Reinforced insulation  – 2 500  3 000  2,4 U +  2 400  
a For multi -phase appliances, the line to neutral or line to earth voltage is used for rated voltage. The test 
voltage for 480 V multi -phase appliances is that specified for a rated voltage in the range > 150 V and  
≤ 250 V. 
b For appliances having a rated voltage ≤150 V, these test voltages apply to parts having a working voltage  > 
150 V and ≤ 250 V. 
c In constructions where basic insulation  and supplementary insulation cannot be tested separately, the 
insulation is subjected to the test voltages specified for reinforced insulation . 
 
A test voltage is applied between accessible metal parts and the supply cord  which is 
wrapped  with metal foil at the point where the supply cord is located in an inlet bushing and 
where, for appliances having a type X attachment , the supply cord is located in a cord guard 
or a cord anchorage with their clamping screws, if any, being tightened to t wo-thirds of the  – 60 – IEC 60335- 1:2020 ©  IEC 20 20        torque specified in Table 14 . The test voltage is 1 250 V for class 0 appliances and class I 
appliances  and 1 750 V for class II applia nces . 
During the test care shall be taken to avoid overstressing  
– the components of electronic circuits; 
– the basic insulation  or the supplementary insulation  when applying the voltage to 
reinforced insulation in class II constructions incorporating both reinforced insulation 
and double insulation. 
NOTE  1 The characteristics of the high- voltage source used for the test are described in Table 5. 
NOTE  2 When testing insulating coatings, the metal foil can be pressed against the insulation by means of a 
sandbag so that the pressure is approximately 5  kPa. The test can be limited to places where the insulation is likely 
to be weak, f or example where there are sharp metal edges under the insulation.  
NOTE  3 If practicable, insulating linings can be tested separately.  
No breakdown shall occur during the test.  
Glow discharges without a drop in voltage are neglected.  
17 Overload protection of transformers and associated circuits  
Appliances incorporating circuits supplied from a transformer shall be constructed so that in the 
event of short circuits which are likely to occur in normal use, excessive temperatures do not 
occur in the transformer or in the circuits associated with the transformer.  
NOTE  Examples are the short- circuiting of bare or inadequately insulated conductors of  accessible circuits  
operating at safety extra- low voltage. 
Compliance is checked by applying the most unfavourable short circuit or overload which is likely to occur in normal use, the appliance being supplied with 1,06 times or 0,94 times rated 
voltage, whichever is the more unfavourable. Basic insulation is not short circuited.  
The temperature rise of the insulation of the conductors of safety extra- low voltage  circuits 
shall not exceed the relevant value specified in Table 3 by more than 15 K. 
The temperature of windings shall not exceed the values specified in Table 8. However, these 
limits do not apply to fail -safe transformers complying with  Subclause 15.5  of IEC 61558 -1:2017 . 
18 Endurance  
NOTE  Requirements and tests can be specified in part 2.  
19 Abnormal operation  
19.1  Appliances shall be constructed so that as a result of abnormal or careless operation, 
the risk of fire, mechanical damage impairing s afety or protection against electric shock is 
obviated as far as is practicable.  
Electronic circuits shall be designed and applied so that a fault condition will not render the 
appliance unsafe with regard to electric shock, fire hazard, mechanical hazard or dangerous 
malfunction . 
Appliances incorporating heating elements are subjected to the tests of 19.2 and 19.3 . In 
addition, such appliances having a control that limits the temperature during the test o f IEC 60335- 1:2020 © IEC 2020 – 61 –          Clause  11 are subjected to the tests of 19.4  and, when applicable, to the  test of 19.5. Appliances 
incorporating PTC heating elements  are subjected to the test of 19.6 . 
Appliances incorporating motors are subjected to the tests of 19.7 to 19.10 , as applicable.  
Appliances incorporating electronic circuits are subjected to the tests of 19.11 and 19.12 , as 
applicable.  
Appliances incorporating contactors or relays are subjected to the test of 19.14. 
Appliances incorporating voltage selector switches are subjected to the test of 19.15. 
Appliances having a mains connection and batteries  that are replaceable are subjected to the 
test of 19.16. 
Appliances incorporating batteries  that are rechargeable and use metal -ion chemistries are 
subjected to the test of 19.17 . 
Unless otherwise specified, the tests are continued until a non-self-resetting thermal cut -out 
operates or until steady conditions are established. If a heating element or an intentionally 
weak part  becomes permanently open- circuited, the relevant test is repeated on a second 
sample. That same part on the second sample shall also become permanently open -circuited 
in the second test, unless a non- self-resetting thermal cut -out operates or steady conditions 
are established.  
NOTE  Fuses, thermal cut -outs , overcurrent protection devices, or similar devices incorporated in the appliance, 
can be used to provide the necessary protection. The protective device in the fixed wiring does not provide the 
necessary protection.  
Unless otherwise specified, only one abnormal  condition is simulated at any one time.  
If more than one of the tests are applicable to the same appliance, these tests are carried out 
consecutively after the appliance has cooled down to room temperature . 
For combined appliances , the tests are carried out with motors and heating elements 
operating simultaneously under normal operation, the appropriate tests being applied one at 
a time to each motor and heating element.  
When it is stated that a control is short -circuited, it may b e rendered inoperative instead.  If the 
control performs more than one function, only that aspect of the control under consideration is rendered inoperative. Other functions of the control may continue to operate normally.  
Unless otherwise specified, compli ance with the tests of this clause is checked as described in 
19.13. 
19.2  Appliances with heating elements are tested under the conditions specified in Clause  11 
but with restricted heat dissipation. The supply voltage, determined prior to the test, is that 
required to provide a power input of 0,85 times rated power input  under normal operation  
when the power input has stabilized. This voltage is maintained throughout the test.  
NOTE  Controls that operate during the test of Clause  11 are allowed to operate.  
19.3  The test of 19.2 is repeated but with a supply voltage, determined prior to the test, equal 
to that required to provide a power input of 1,24 times rated power input  under normal 
operation  when the power input has stabilized. This voltage is maintained throughout the test.  
NOTE  Controls that operate during the test of Clause  11 are allowed to operate.   – 62 – IEC 60335- 1:2020 ©  IEC 20 20        19.4  The appliance is tested under the conditions specified in Clause  11. Any control that 
limits the temperature during the test of Clause  11 is short -circuited.  
If the appli ance incorporates more than one control, they are short -circuited in turn.  
19.5  The test of 19.4  is repeated on class 0I appliances and class I appliances incorporating 
tubular sheathed or embedded heating elements. However, controls are not short -circuited but 
one end of the element is connected to the sheath of the heating element.  
A control that operates during this test and the test of Clause  11 and that incorporates an 
electronic circuit is not considered to be a protective electronic circuit if the appliance 
complies with 19.13 with the electronic control rendered inoperative.  
This test is repeated with the polarity of the supply to the appliance reversed and with the other 
end of the element connected to the sheat h. 
The test is not carried out on appliances : 
– intended to be permanently connected to fixed wiring;  
– where an all-pole disconnection occurs during the test of 19.4 ; or 
– used in a system with polarized plugs intended for connection to polarized socket outlets.  
Appliances with a neutral are tested with the neutral connected to the sheath.  
NOTE  For embedded heating elements, the metal enclosure is considered to be the sheath.  
19.6  Appliances with PTC heating elements  are supplied at rated voltage  until steady 
conditions with regard to power input and temperature are established.  
The working voltage  of the PTC heating element  is increased by 5  % and the appliance is 
operated unt il steady conditions are re- established. The voltage is then increased in similar 
steps until 1,5 times working voltage  is reached, or until the PTC heating element  ruptures, 
whichever occurs first.  
19.7  The appliance is operated under stalled conditions by : 
– locking the rotor of appliances for which the locked rotor torque is smaller than the full load 
torque;  
– locking moving parts of other appliances.  
If an appliance has more than one motor, the test is carried out for each motor separately.  
Appliances incorporating motors and having capacitors in the circuit of an auxiliary winding, are operated with the rotor locked, the capacitors being open- circuited one at a time. The test is 
repeated with the capacitors short -circuited one at  a time, unless they are of class  S2 or S3 of 
IEC 60252 -1:2010 including IEC 60252 -1:2010/AMD1:2013. 
NOTE 1  This test is carried out with the rotor locked since some motors can start thus giving rise to inconsistent 
results.  
For each of the tests, appliances provided with a timer or programmer are supplied at rated voltage for a period equal to the maximum period allowed by the timer or programmer.  If the 
timer or programmer is an electronic type that operates to ensure compliance with the test 
before the m aximum period under the conditions of Clause 11 is reached, it is considered to be 
a protective electronic circuit as well as a control that operates under the conditions of 
Clause  11. 
Other appliances are supplied at rated voltage for a period: IEC 60335- 1:2020 © IEC 2020 – 63 –          – of 30  s for  
• hand -held appliances; 
• appliances that have to be kept switched on by hand or foot ; and 
• appliances that are continuously loaded by hand . 
– of 5 min for other appliances that are operated while attended;  
– until steady conditions are established, for other appliances.  
NOTE 2  Appliances that are tested for 5 min are indicated in the relevant part 2.  
During the test, the temperature of the windings shall not exceed the relevant value specified 
in Table 8. 
Table 8 – Maximum winding temperature  
Type of appliance  Temperature  
°C 
Class  
105 
(A) Class  
120 
(E) Class  
130 
(B) Class  
155 
(F) Class  
180 
(H) Class  
200 
(N) Class  
220 
(R) Class  
250 
Appliances other than those operated 
until steady conditions are established  200 215 225 240 260 280 300 330 
Appliances operated until steady conditions are established          
– if impedance protected  150 165 175 190 210 230 250 280 
– if protected by a protective device          
 • during the first hour, maximum value  200 215 225 240 260 280 300 330 
 • after the first hour, maximum  value  175 190 200 215 235 255 275 305 
 • after the first hour, arithmetic 
average  150 165 175 190 210 230 250 280 
 
19.8  One phase of appliances incorporating multi -phase  motors is disconnected. The 
appliance is then operated under normal operation and supplied at rated voltage for the 
period specified in 19.7 . 
19.9  A running overload test is carried out on appliances incorporating motors that are 
intended to be remotely or automatically controlled or liable to be operated continuously.  
Motor- operated ap pliances  and combined appliances  for which Subclause 30.2.3 is 
applicable and that use overload protective devices relying on electronic circuits  to protect 
the motor windings,  other than those that sense winding temperatures directly, are also 
subjected to the running overload test. 
The appliance is operated under normal operation  and supplied at rated voltage  until steady 
conditions are established. The load is then increased so that the current through the motor 
windings is raised by 10  % and the appliance is operated again until steady conditions are 
established, the supply voltage being maintained at its original value. The load is again increased and the test  is repeated until the protective device operates or the motor stalls.  
During the test, the winding temperature shall not exceed : 
– 140 °C, for class 105 (A) winding insulation;  
– 155 °C, for class 120 (E) winding insulation;  
– 165 °C, for class 130 (B) winding insulation;  
– 180 °C, for class 155 (F) winding insulation;   – 64 – IEC 60335- 1:2020 ©  IEC 20 20        – 200 °C, for class 180 (H) winding insulation;  
– 220 °C, for class 200 (N) winding insulation;  
– 240 °C, for class 220 (R) winding insulation;  
– 270 °C, for class 250 winding insulation.  
NOTE  If the load c annot be increased in appropriate steps, the motor can be removed from the appliance and tested 
separately.  
19.10  Appliances incorporating series motors are operated with the lowest possible load and 
supplied at 1,3 times rated voltage for 1 min.  
During the test, parts shall not be ejected from the appliance.  
19.11  Electronic circuits are checked by evaluation of the fault conditions specified in 19.11.2 
for all circuits or parts of circuits, unless they comply with the conditions specified in 19.11.1 . 
NOTE  1 In general, examination of the appliance and its circuit diagram will reveal the fault conditions which have 
to be simulated, so that testing can be lim ited to those cases that can  be expected to give the most unfavourable 
results.  
Appliances incorporating an electronic circuit  that relies upon a programmable component to 
function correctly are subjected to the test of 19.11.4.8, unless restarting at any point in the 
operating cycle after interruption of operation due to a supply voltage dip will not result in a 
haza rd. The test is carried out after removal of all batteries  and other components intended to 
maintain the programmable component supply voltage during mains supply voltage dips, 
interruptions and variations.  
Appliances having a device with an off position  obtained by electronic disconnection, or a 
device that can place the appliance in a stand- by mode, are subjected to the tests of 19.11.4 . 
NOTE  2 For information on general guidance relating to the sequence of tests for the evaluation of electronic 
circuits , reference can be made to informative Annex  Q. It should be realized that in the Parts 2 there can be 
additional or alternative abnormal operation tests specified; these are not shown in the flow chart. For correct 
application of this standard, the normative text takes precedence over the guidance given in in formative Annex  Q. 
If the safety of the appliance under any of the fault conditions depends on the operation of a 
miniature fuse -link complying with IEC 60127, the test of 19.12 is carried out.  
During and after each test, the temperature of windings shall not exceed the values specified 
in Table 8. However, these limits do not apply to fail -safe transformers complying with 
Subclause 15.5 of IEC 61558 -1:2017. The appliance shall comply with the conditions specified 
in 19.13. Any current flowing through protective impedance  shall not exceed the limits 
specified in 8.1.4. 
NOTE  3 Unless it is necessary to replace components after any of the tests, the electric strength test required by 
19.13 need only be carried out after the final test on the electronic circuit . 
If a conductor of a printed circuit board becomes open -circuited, the appliance is considered to 
have withstood the particular test, provided both of the following  conditions are met:  
– the base material of the printed circuit board withstands the test of normative  Annex  E; 
– any loosened conductor does not reduce clearances or creepage distances  between live 
parts  and accessible metal parts  below the values specified in Clause 29. 
19.11.1  Fault conditions a) to g) specified in 19.11.2  are not applied to circuits or parts of 
circuits when both of the following conditions are met:  
– the electronic circuit  is a low -power circuit as described below;  
– protection against electric shock, fire hazard, mechanical hazard or dangerous 
malfunction  of other parts of the appliance does not rely on the correct functioning of the 
electronic circuit . IEC 60335- 1:2020 © IEC 2020 – 65 –          An example of a low -power circuit is shown in Figure 6 and is determined as follows.  
The appliance is supplied at rated voltage  and a variable resistor, adjusted to its maximum 
resistance, is connected between the point to be investigated and the opposite pole of the 
supply source. The resistance is then d ecreased until the power consumed by the resistor 
reaches a maximum. Points closest to the supply source at which the maximum power delivered 
to this resistor does not exceed 15  W at the end of 5 s are called low -power points. The part of 
the circuit farth er from the supply source than a low- power point is considered to be a low -
power circuit.  
The measurements shall be made from only one pole of the supply source, preferably the one 
that gives the fewest low -power points. The power consumed by the variable resistor shall be 
measured by a wattmeter.  
When determining the low -power points, it is recommended to start with points close to the 
supply source.  
19.11.2  The following fault conditions are considered and, if necessary, applied one at a time, 
consequential fault s being taken into consideration:  
a) short circuit of functional insulation  if clearances or creepage distances  are less than 
the values specified in Clause  29; 
b) open circuit at the terminals of any component;  
c) short circuit of capacitors, unless they comply with IEC 60384 -14:2013 including 
IEC 60384 -14:2013/AMD1:2016 ; 
d) short circuit of any two terminals of an electronic component , other than an integrated 
circuit. This fault condition is not applied between the two circuits of an optocoupler;  
e) failure of triacs in the diode mode;  
f) failure of microprocessors and integrated circuits except components such as thyristors and 
triacs . All possible output signals are considered for faults occurring within the component. 
If it can be shown that a particular output signal is unlikely to occur, then the relevant fault is not consider ed; 
g) failure of an electronic power switching device in a partial turn -on mode with loss of gate 
(base) control . 
NOTE  1 This mode can be simulated by disconnecting the electronic power switching device gate (base) terminal 
and connecting an external adjustable power supply between the gate (base) terminal and the source (emitter) terminal of the electronic power switching device. The power supply is then varied so as to achieve a current that 
will not damage the electronic power switching device but will give the most onerous conditions of test.  
NOTE  2 Examples of electronic power switching devices are field effect transistors (FET’s and MOSFET’s) and 
bipolar transistors (including IGBT’s).  
Fault condition f) is applied to encapsulated and similar components if the circuit cannot be 
assessed by other methods.  
Positive temperature coefficient resistors are not short -circuited if they are used within the 
manufacturer's specification. However, PTC -S thermistors are short -circuited unless they 
comply with IEC 60738 -1. 
In addition, each low -power circuit is short -circuited by connecting the low- power point to the 
pole of the supply source from which the measurements were made.  
Any cord provided between a battery -operated appliance  that consumes more than 15  W and 
the detachable power supply part  shall be short -circuited at the point along its length likely 
to produce the most adverse effects.   – 66 – IEC 60335- 1:2020 ©  IEC 20 20        For simulation of the fault conditions, the appliance is operated under the conditions specified 
in Clause 11 but supplied at rated voltage . 
When any of the fault conditions are simulated, the duration of the test is : 
– as specified in 11.7 but only for one operating cycle and only if the fault cannot be 
recognized by the user, f or example, a change in temperature;  
– as specified in 19.7, if the fault can be recognized by the user, for example, when the motor 
of a kitchen machine stops;  
– until s teady conditions are established, for circuits continuously connected to the supply 
mains, for example, stand -by circuits.  
In each case, the test is ended if a non- self-resetting interruption of the supply occurs within 
the appliance.  
19.11.3  If the appliance incorporates a protective  electronic circuit  that operates to ensure 
compliance with Clause 19, the appliance is tested as follows:  
A fault as indicated in a) to g) of 19.11.2  shall be incorporate d in the protective electronic 
circuit either before the appliance is started or at any point in time after the appliance is started 
so that the most unfavourable conditions of the test are applied.  
If the appliance is able to operate after the fault in th e protective electronic circuit  is 
incorporated, then the appliance is further tested as follows.  
For appliances for continuous operation the appliance is operated until steady conditions are 
reached. Then the relevant test of Clause 19 is repeated.  
Other appliances are operated for one cycle of operation. Then the relevant test of Clause 19 
is repeated.  
Compliance is checked as specified in 19.13. 
19.11.4  Appliances having a device with an off position obtained by electronic disconnection, 
or a device that can be placed in the stand- by mode, are subjected to the tests of 19.11.4.1 to 
19.11.4.7. The tests are carried out with the appliance supplied at rated voltage, the device 
being set in the off position  or in the stand- by mode.  
Appliances incorporating a protective electronic circuit  are subjected to the tests of 19.11.4.1  
to 19.11.4.7 . The tests are carried out after the protective electronic circuit  has operated 
during t he relevant tests of Clause  19 except 19.2 , 19.6  and 19.11.3. However, the tests for 
electromagnetic phenomena are not applied to protective electronic circuits  that operate 
during the test of 19.7  in appliances that are used while attended.  
The tests are carried out with surge protective devices  disconnected, unless they incorporate 
spark gaps.  
If the appliance has several modes of operation, the tests are carried  out with the appliance 
operating in each mode, if necessary.  
NOTE  Appliances incorporating electronic controls complying with the IEC  60730 series of standards are not 
exempt from the tests.  IEC 60335- 1:2020 © IEC 2020 – 67 –          19.11.4.1  The appliance is subjected to electrostatic discharges in accordance with 
IEC 61000 -4-2, test level 4 being applicable. Ten discharges having a positive polarity and ten 
discharges having a negative polarity are applied at each preselected point.  
19.11.4.2  The appli ance is subjected to radiated fields in accordance with IEC 61000-4- 3. 
The frequency ranges tested shall be: 
– 80 MHz to 1 000  MHz, test level 3 ; 
– 1,4 GHz to 2,0  GHz, test level 3;  
– 2,0 GHz to 2,7  GHz, test level 2.  
The dwell time for each frequency is to be s ufficient to observe a possible malfunction of the 
protective electronic circuit . 
19.11.4.3  The appliance is subjected to fast transient bursts in accordance with IEC 61000-4- 4. 
Test level 3 with a repetition rate of 5 kHz is applicable for signal and control lines. Test level 
4 with a repetition rate of 5 kHz is applicable for the power supply lines. The bursts are applied 
for 2  min with a positive polarity and for 2 min with a negative polarity.  
19.11.4.4  The power supply terminals of the appliance are subjected to voltage surges in 
accordance with IEC 61000-4- 5, five positive impulses and five negative impulses being applied 
at the selected points.  An open circuit test voltage of 2 kV is applicable for the  line-to-line 
coupling mode, a generator having a source impedance of 2  Ω being used. An open circuit test 
voltage of 4 kV is applicable for the line- to-earth coupling mode, a generator having a source 
impedance of 12  Ω being used . 
Earthed heating elements  in class I appliances  are disconnected during this test.  
NOTE  If a feedback system depends on inputs related to a disconnected heating element, an artificial network can 
be needed.  
For appliances having surge arresters incorporating spark gaps, the test i s repeated at a level 
that is 95  % of the flashover voltage.  
19.11.4.5  The appliance is subjected to injected currents in accordance with IEC  61000-4- 6, 
test level 3 being applicable. During the test, all frequencies between 0,15  MHz to 80  MHz are 
covered.  
The dwell  time for each frequency is to be sufficient to observe a possible malfunction of the 
protective electronic circuit . 
19.11.4.6  For appliances having a rated current  not exceeding 16 A, the appliance is 
subjected to the class 3 voltage dips and interruptions in accordance with IEC 61000-4- 11:20 20. 
The values specified in Table 1 and Table 2 of IEC  61000-4- 11:2020 are applied at zero 
crossing of the supply voltage.  
For appliances having  a rated current  exceeding 16  A, the appliance is subjected to the class 
3 voltage dips and interruptions in accordance with IEC  61000-4- 34:2005 including 
IEC 61000 -4-34:2005/AMD1:2009 . The values specified in Table 1 and Table 2 of 
IEC 61000 -4-34:2005 inc luding IEC 61000 -4-34:2005/AMD1:2009 are applied at zero crossing 
of the supply voltage.  
19.11.4.7  The appliance is subjected to mains signals in accordance with 
IEC 61000 -4-13:2002 including IEC 61000-4- 13:2002/AMD1:2009 and  – 68 – IEC 60335- 1:2020 ©  IEC 20 20        IEC 61000 -4-13:2002/AMD2:2015 , Table 11 with test level class 2 using the frequency steps 
according to Table  10. 
19.11.4.8  The appliance is supplied at rated voltage and operated under normal operation. 
After approximately 60  s, the power supply voltage is reduced to a level such that the appliance 
ceases to respond to user inputs or parts controlled by the programmable component cease to 
operate, whichever occurs first. This value of supply voltage is recorded. The appliance is 
supplied at rated voltage and operated under norma l operation. The voltage is then reduced 
to a value of approximately 10 % less than the recorded voltage. It is held at this value for 
approximately 60  s and then increased to rated voltage. The rate of decrease and increase of 
the power supply voltage is to be approximately 10 V/s. 
The appliance shall continue to either operate normally from the same point in its operating 
cycle at which the voltage decrease occurred or a manual operation shall be required to restart it. 
19.12  If safety of the appliance depends upon the operation of a miniature fuse -link complying 
with IEC  60127 during any of the fault conditions specified in 19.11.2 , the test is repeated but 
with the miniature fuse -link replaced by an ammeter. If the current measured : 
– does not exceed 2,1 times the current  rating of the fuse- link, the circuit is not considered to 
be adequately protected and the test is carried out with the fuse -link short -circuited;  
– is at least 2,75 times the current  rating of the fuse -link, the circuit is considered to be 
adequately protected;  
– is between 2,1 times and 2,75 times the current  rating of the fuse- link, the fuse link is short -
circuited and the test is carried out  
• for the relevant period or for 30  min, whichever is the shorter, for quick acting fuse- links; 
• for the relevant period or for 2  min, whichever is the shorter, for time lag fuse -links.  
In case of doubt, the maximum resistance of the f use- link shall be taken into account when 
determining the current.  
NOTE 1 The verification whether the fuse- link acts as a protective device is based on the fusing characteristics 
specified in IEC  60127, which also gives the information necessary to calculate the maximum resistance of the fuse-
link. 
NOTE 2 Other fuses are considered to be intentionally weak parts in accordance with 19.1 . 
19.13  During the tests, the app liance shall not emit flames, molten metal, or poisonous or 
ignitable gas in hazardous amounts and temperature rises shall not exceed the values shown in Table 9. 
After the tests, and when the appliance has cooled to approximately room temperature , 
compliance with Clause  8 shall not be impaired and the appliance shall comply with 20.2 if it 
can still be operated.  IEC 60335- 1:2020 © IEC 2020 – 69 –          Table 9 – Maximum abnormal temperature rise 
Part  Temperature rise  
 K 
Wooden supports, walls, ceiling and floor of the test corner and wooden 
cabinets a 150 
Insulation of the supply cord  a without T marking, or with T marking up to 
75 °C 150 
Insulation of the supply cord  a with T marking above 75 °C T+75  
Supplementary insulation  and reinforced insulation  other than thermoplastic 
materials b 1,5 times the relevant value 
specified in Table 3  
a For motor -operated appliances, these temperature rises are not determined.  
b There is no specific limit for supplementary insulation  and reinforced insulation  of thermoplastic material. 
However, the temperature rise has to be determined so that the test of 30.1 can be carried out.  
 
When the insulation, other than that of class III appliances or class III constructions that do 
not contain live parts , has cooled down to approximately room temperature, it shall withstand 
the electric strength test of 16.3 , the test voltage, however, being as specified in Table 4. 
The humidity treatment of 15.3  is not applied before this electric strength test.  
For appliances which are immersed in or filled with conducting liquid in normal use, the 
appliance is immersed in or filled with water for 24  h before the electric strength test is carried 
out. 
After the operation or interruption of a control, clearances  and creepage distances across the 
functional insulation shall withstand the electric strength test of 16.3, the test voltage, 
however, being twice the working voltage . 
The appliance shall not undergo a dangerous malfunction , and there shall be no failure of 
protective electronic circuits  if the appliance is still operable.  
During and after the tests, the no- load output voltage of an accessible safety extra- low 
voltage outlet or connector or Universal Serial Bus (USB) outlet shall not have increased by 
more than 3  V or 10  % of its no- load output voltage in normal use, whichever is higher , with a 
maximum of 42,4 V for DC and a peak value of 42,4  V for AC . 
Appliances tested with an electronic switch in the off position , or in the stand -by mode, shall : 
– not become operational ; or 
– if they become operational, not result in a dangerous malfunction during or after the tests 
of 19.11.4. 
NOTE  Unintended operation that could  impair safety can result from careless use of appliances, such as: 
– storage of small appliances while connected to the supply;  
– placing flammable material on working surfaces of heating appliances; or  
– placing objects in areas near motorized appliances that are not expected to star t. 
In an appliance containing lids or doors that are controlled by one or more interlocks, one of the interlocks may be released provided that both of the following conditions are fulfilled:  
– the lid or door does not move automatically to an open position when the interlock is 
released;  
– the appliance will not restart after the cycle in which the interlock was released.   – 70 – IEC 60335- 1:2020 ©  IEC 20 20        19.14  Appliances are operated under the conditions of Clause  11. Any contactor or relay 
contact that operates under the conditions of Clause  11 is short -circuited.  
If a relay or contactor with more than one contact is used, all contacts are short -circuited at the 
same time.  
Any relay or contactor which operates only in order to ensure that the appliance is energized 
for normal use and that does not otherwise operate in normal use is not short -circuited.  
If more than one relay or contactor operates in Clause  11, each such relay or contactor is short-
circuited in turn.  
If the appliance has several modes of operation, the tests are carried out with the appliance 
operating in each mode, if necessary.  
19.15  For appliances incorporating a mains voltage selector switch, this switch is set to the 
lowest rated voltage  position and the highest value of rated voltage  is applied.  
19.16  Appliances having mains connection and batteries that are replaceable by the user are 
supplied at rated voltage  and operated under normal operation  but with the batteries 
removed or in any position allowed by the construction.  
NOTE  The intent is to determine that safe operation does not depend upon the presence of a battery  voltage.  
19.17  Battery- operated appliances incorporating a battery  that uses metal -ion chemistry, the 
charging system  and battery  are checked by the following tests.  
The battery system  is operated as specified in the appliance manufacturer’s instructions under 
the abnormal conditions listed below in a) to d). Each test is conducted until the test sample returns to room temperature , for at least 7  h or until twice the normal charge perio d has 
elapsed, whichever is longer.  
a) the state of the battery  is as follows:  
– a series configured battery shall have a deliberate imbalance. The imbalance is 
introduced into a battery  that has been fully discharged by charging one cell  to the 
percentage of b eing fully charged  applied during the test of Clause  12; 
– a single cell or parallel only configuration battery  shall be fully discharged . 
b) If the test of Clause  12 is conducted with an imbalance of less than 50 % due to the function 
of circuit ry intended for maintaining balance between cells in the battery and if a single 
fault of any component within that circuit ry is shown to result in the loss of that function, 
then a series configured battery  shall be fully charged  with a deliberate imbalance. The 
imbalance is introduced into a battery  that has been fully discharged by charging one cell 
to approximately 50  % of being fully charged . 
c) For a battery  with a series configuration, all cells  are at approximately 50  % of being fully 
charged , except for one which is shorted. The battery  is then fully charged . 
d) With a battery  that is fully charged connected to the charging system , a short  circuit  is 
introduced to the charging system  across a component or between adjacent printed circuit 
tracks at a location expected to produce the most unfavourable results to evaluate the effect 
of back -feed from the battery . In addition, for a charging system  with a cord that connects 
to the battery , the short circuit shall be introduced at the point likely to produce the most 
adverse effects. The resistance of the short circuit shall not exceed 10 mΩ. 
No explosion or ignition of the battery  shall occur during or after the test. However, venting  of 
the cells  is permitted provided that they have not vented by any means other than through their 
vents.  IEC 60335- 1:2020 © IEC 2020 – 71 –          The voltage on any cell shall not exceed the upper limit charging voltage  by more than 
150 mV unless the charging system  is permanently disabled from recharging t he battery . 
To determine if recharging is permanently disabled, the battery  shall be discharged to 
approximately 50  % of being fully charged, by using the battery- operated appliance  tested 
(in the case of an integral battery) or by using a new sample of the battery -operated 
appliance  (in the case of a detachable battery and separable battery). An attempt is then 
made to recharge the battery  normally. There shall be no charging current after 10  min or after 
25 % of the nominal capacity has been delivered, whichever occurs first.  
20 Stability and mechanical hazards  
20.1  Appliances, other than fixed appliances and hand- held appliances , intended to be 
used on a surface such as the floor or a table, shall have adequate stability.  
Compliance is checked by the following test, appliances incorporating an appliance inlet being 
fitted with an appropriate connector and flexible cord.  
The appliance, not connected to the supply mains, is placed in any normal position of use on a 
plane inclined at an angle of 10° to the horizontal, the supply cord resting on the inclined plane 
in the most unfavourable position. However, if part of an appliance comes into contact with the 
horizontal supporting surface when the appliance is tilted through an angle of 10°, the appliance is placed on a horizontal support and tilted in the most unfavourable direction through an angle 
of 10°.  
The test on the horizontal support may be necessary for appliances provided with rollers, castors or feet. In this case, castors or wheels may be blocked to prevent the appliance from 
rolling.  
Appliances provided with doors are tested with the doors open or closed, whichever is the more 
unfavourable.  
Appliances intended to be filled with liquid by the user in normal use are tested empty or filled with the most unfavourable quantity of water up to the capacity indicated in the instructions.  
The appliance shall not overturn.  
The test is repeated on appliances with heating elements with the angle of inclination increased 
to 15°. If the appliance overturns in one or more positions, it is subjected to the tests of 
Clause  11 in each of these overturned positions.  
During this test, temperature rises shall not exceed the values shown in Table 9. 
20.2  Moving parts of appliances shall, as far as is compatible with the use and working of the 
appliance, be positioned or enclosed to provide adequate protection against personal injury in 
normal use.  This requirement does not apply to parts of an appliance that necessarily have to 
be exposed to allow the appliance to perform its working function.  
NOTE 1  Examples of parts of appliances necessarily exposed to perform the working function include the needle 
of a sewing machine, rotating brushes of vacuum cleaner and the blade of an electrical knife.  
Protective enclosures, guards and similar parts shall be non- detachable parts  and shall have 
adequate mechanical strength. However, enclosures that can be opened by overriding an interlock by applying the test probe are considered to be detachable parts . 
The unexpected closure of self-resetting  thermal cut -outs  and overcurrent protective 
devices  shall not cause a hazard.   – 72 – IEC 60335- 1:2020 ©  IEC 20 20        NOTE 2  An example of an appliance in which self -resetting  thermal cut -outs  and overcurrent protective devices 
could cause a hazard is an appliance having parts that are necessarily exposed so that it can perform its working 
function. 
Compliance is checked by : 
– inspection;  
– the test of 21.1 ; 
– applying a force not exceeding 5 N by means of a test probe that is similar to test probe B 
of IEC 61032 but having a circular stop face with a diameter of 50 mm, instead of the non-
circular face; and 
– applying test probe 18 of IEC 61032 with a force not exceeding 2,5 N. 
Test probe 18 is not applied to appliances for commercial use unless they are intended to be 
installed in an area open to the public.  
For appliances provided with movable devices such as those intended for varying the tension 
of belts, the test with the test probe is carried out with these devices adjusted to the most 
unfavourable position within their range of adjustment. If necessary, belts are removed.  
It shall not be possible to touch dangerous moving parts with the test probes.  
21 Mechanical strength  
21.1  Appliances shall have adequate mechanical strength and be constructed to withstand 
such rough handling that may be expected in normal use.  
Compliance is checked by applying blows to the appliance in accordance with test Ehb of IEC 60068 -2-75, th e spring hammer test.  
The appliance is rigidly supported and three blows, having an impact energy of 0,5  J, are 
applied to every point of the enclosure that is likely to be weak.  
If necessary, the blows are also applied to handles, levers, knobs and similar parts and to signal lamps and their covers but only if the lamps or covers protrude from the enclosure by more than 
10 mm or if their surface area exceeds 4  cm
2. Lamps within the appliance and their covers are 
only tested if they are likely to be damaged  in normal use.  
When applying the release cone to the guard of a visibly glowing heating element , the 
hammer head passing through the guard shall not strike the heating element.  
For appliances and parts of appliances having pins for insertion into mains socket -outlets, 
compliance is checked by subjecting the part of the appliance incorporating the pins to the test, 
Free fall  repeated, procedure 2, of IEC 60068-2- 31. 
The number of falls is : 
– 100, if the mass of the part does not exceed 250  g; 
– 50, if t he mass of the part exceeds 250  g. 
The height of the falls is 500 mm. 
After the test s, the appliance shall show no damage that could impair compliance with this 
standard and compliance with 8.1, 15.1 and Clause  29 shall not be impaired. In case of doubt, 
supplementary insulation  and reinforced insulation  are subjected to the electric strength 
test of 16.3 . IEC 60335- 1:2020 © IEC 2020 – 73 –          Damage to the finish, small dents that do not reduce clearances or creepage distances below 
the values specified in Clause  29, and small chips that do not adversely affect protection against 
access to live parts  or moisture, are ignored.  
If a decorative cover is protected by an inner cover, fracture of the decorative cover is ignored 
if the inner cover itself withstands the test.  
If there is doubt as to whether a defect has occurred by the application of the preceding blows 
or the previous tests, this defect is neglected and the group of three blows is applied to the 
same place on a new sample which shall then withstand the te st. 
Cracks not visible to the naked eye and surface cracks in fibre -reinforced mouldings and similar 
materials are ignored.  
21.2  Accessible parts of solid insulation shall have sufficient strength to prevent penetration 
by sharp implements.  
Compliance is checked by subjecting the insulation to the following test, unless the thickness 
of supplementary insulation is at least  1 mm and that of reinforced insulation is at least  
2 mm. 
The insulation is raised to the temperature measured during the test of Clause  11. The surface 
of the insulation is then scratched by means of a hardened steel pin, the end of which has the 
form of a cone with an angle of 40°. Its  tip is rounded with a radius of 0,25  mm ± 0,02  mm. The 
pin is held at any angle from 80° to 85° to the horizontal and loaded so that the force exerted along its axis is 10  N 
± 0,5 N. The scratches are made by drawing the pin along the surface of 
the insul ation at a speed of approximately 20 mm/s. Two parallel scratches are made. They are 
spaced sufficiently apart so that they are not affected by each other, their length covering 
approximately 25  % of the length of the insulation. Two similar scratches are made at 90° to 
the first pair without crossing them.  
The test fingernail of Figure 7 is then applied to the scratched surface with a force of 
approximately 10  N. No further damage, such as separation of the material, shall occur. The 
insulation shall then withstand the electric strength test of 16.3. 
The hardened steel pin is then applied perpendicularly with a force of 30  N ± 0,5 N to an 
unscratched part of the surface. The insulation shall then withstand the electric strength test of 
16.3 with the pin still applied and used as one of the electrodes.  
21.3  Appliances with pins for insertion into socket -outlets where the plug part is capable of 
rotation shall be provi ded with a mechanical stop to prevent rotation beyond which stress to 
electrical connections and internal wiring may occur. The mechanical stop shall have adequate mechanical strength and be constructed to withstand such rough handling that may
 be expected 
in normal use.  
Compliance is checked by inspection and by the following test. 
The part relying upon the mechanical stop shall be rotated as intended until the mechanical 
stop prevents further rotation. A torque of 2  Nm is then applied for 1  min in an atte mpt to 
override the mechanical stop. The part relying upon the mechanical stop shall not rotate.  
The test shall be repeated in the opposite direction of rotation.   – 74 – IEC 60335- 1:2020 ©  IEC 20 20        22 Construction  
22.1  If the appliance is marked with the first numeral of the IP system or any of the additional 
letters of the IP system, the relevant requirements of IEC  60529 :1989 including 
IEC 60529:1989/AMD1:199 9 and IEC 60529:1989/AMD2:2013 shall be fulfilled.  
Compliance  is checked by the relevant tests.  
22.2  For stationary appliances , means shall be provided to ensure disconnection from the 
supply mains. Such means shall be one of the following:  
– a supply cord fitted with a plug;  
– a switch providing all-pole disconnection  and complying with 24.3 ; 
– a statement in the instructions that a disconnection incorporated in the fixed wiring is to be 
provided;  
– an appliance inlet.  
Single-pole switches and single- pole protective devices  that disconnect heating elements from 
the supply mains in single- phase, permanently connected class 0I appliances and class I 
appliances  shall be connected to the line conductor.  
Compliance is checked by inspection.  
22.3  Appliances with pins for insertion into socket -outlets shall not impose undue strain on 
these socket -outlets. The means for retaining the pins shall withstand the forces to which the 
pins are likely to be subjected in normal use.  
Compliance is checked by inserting the pins of the appliance into a socket -outlet. The socket -
outlet has a horizontal pivot at a distance of 8 mm behind the engagement face of the socket -
outlet and in the plane of the contact apertures.  
The torque that has  to be applied to maintain the engagement face of the socket -outlet in the 
vertical plane shall not exceed 0,25  Nm. The torque to keep the socket -outlet itself in the vertical 
plane is not included in this value.  
A new sample of the appliance is firmly hel d so that the retention of the pins is not affected. 
The appliance is placed in a heating cabinet for 1 h at a temperature of 70 °C ± 2 °C. The 
appliance is then removed from the heating cabinet and a pull force of 50 N is immediately 
applied for 1  min to each pin along their longitudinal axes.  
When the appliance has cooled down to room temperature , the pins shall not have been 
displaced by more than 1 mm. 
Each pin is then subjected in turn to a torque of 0,4 Nm, which is applied for 1  min in each 
direction . The pins shall not rotate unless rotation does not impair compliance with this standard.  
22.4  Appliances for heating liquids and appliances causing undue vibration shall not be 
provided with pins for insertion into socket -outlets.  
Compliance is checked by inspection.  
22.5  Appliances intended to be connected to the supply mains by means of a plug or pins for 
insertion into socket -outlets  shall be constructed so that in normal use, when pins are touched,  IEC 60335- 1:2020 © IEC 2020 – 75 –          there is no risk of electric shock from charged capacitors that result in a capacitance equal to 
or greater than 0,1 µF across any two pins.  
Compliance is checked by the following test.  
The appliance is supplied at rated voltage . Any switch is then placed in the off position  and 
the appliance is disconnected from the supply mains at the instant of voltage peak. One second 
after disconnection, the voltage between the pins of the plug is measured with an instrument 
having an input impedance of not less than 100  MΩ in parallel w ith an input capacitance not 
exceeding 25  pF. 
The voltage shall not exceed 34 V. 
If compliance relies on the operation of an electronic circuit , the electromagnetic phenomena 
tests of 19.11.4.3 and 19.11.4.4 are applied one at a time to the appliance. The test for 
measuring the voltage between the pins of the plug is then repeated three times and for each 
test, the voltage shall not exceed 34  V. 
22.6  Appliances shall be constructed so that their electrical insulation cannot be affected by 
water that could condense on cold surfaces or by liquid that could leak from containers, hoses, couplings and similar parts of the appliance. The electrical insulation of class II appliances  
and class  II constructions  shall not be affected if a hose ruptures or a seal leaks.  
Compliance is checked by inspection and, in case of doubt, by the following test.  
Drops of coloured water solution are applied by a syringe to parts inside the appliance where leakage of a liquid could occur and affect electrical insulation. The appliance is in operation or 
at rest, whichever is the more unfavourable.  
After this test, inspection shall show that there is no trace of liquid on windings or insulation that could result in a reduction of creepage distances  below the values specified in 29.2 . 
22.7  Appliances containing liquid or gases in normal use or having steam -producing devices 
shall incorporate adequate safeguards against the risk of excessive pressure.  
Compliance is checked by inspection and, if necessary, by an appropriate test.  
22.8  For appliances having compartments to which access can be gained without the aid of a 
tool and that are likely to be cleaned in normal use, the electrical connections shall be arranged 
so that they are not subject to pulling during cleaning.  
Compliance is checked by inspection and by manual test.  
22.9  Appliances shall be constructed so that parts such as insulation, internal wiring, windings, 
commutators and slip rings are not exposed to oil, grease or similar substances, unless the 
substance has adequate insulating properties so that compliance with this standard is not 
impaired.  
Compliance is checked by inspection and by the tests of this standard.  
22.10  It shall not be possible to reset voltage- maintained non- self-resetting thermal cut -outs 
by the operation of an automatic switching device incorporated with in the appliance. This 
requirement is only applicable if a non- self-resetting thermal cut -out is required by this 
standard  and a voltage maintained non-self-resetting thermal cut -out is used to meet it.  
NOTE 1  Voltage- maintained controls are intended to automatically reset if they become de- energized.   – 76 – IEC 60335- 1:2020 ©  IEC 20 20        Non-self-resetting thermal motor protectors shall have a trip -free action unless they are 
voltage maintained.  
NOTE 2  Trip-free is an automatic action that is independent of manipulation or position of the actuating member.  
Reset buttons of non- self-resetting controls  shall be located or protected so that their 
accidental resetting is unlikely to occur if this could result in a hazard.  
NOTE 3  For example, this requirement precludes the location of reset buttons on the back of an appliance, which 
could result in them being reset by pushing the appliance against a wall.  
Compliance is checked by inspection.  
22.11  Non-detachable  parts that protect against access to live parts, moisture or contact with 
moving parts shall be fixed in a reliable manner and withstand the mechanical stress occurring 
during normal use. Snap -in devices used for fixing such parts shall have an obvious locked 
position. The fixing properties of snap- in devices used in parts that are lik ely to be removed 
during installation or servicing shall be reliable.  
Compliance is checked by the following tests.  
Parts that are likely to be removed during installation or servicing are disassembled and 
assembled 10 times before the test is carried out.  
NOTE  Servicing includes replacement of the supply cord , except in appliances with a Type Z attachment . 
The test is carried out at room temperature . However, if compliance may be affected by the 
temperature of the appliance, the test is also carried out im mediately after it has been operated 
under the conditions specified in Clause  11. 
The test is applied to all parts that are likely to be detachable whether or not they are fixed by screws, rivets or similar parts.  
A force is applied without jerks for 10  s in the most unfav ourable direction to parts likely to be 
weak. The force is as follows:  
– push force, 50 N; 
– pull force:  
• if the shape of the part is such that the fingertips cannot easily slip off, 50 N; 
• if the projection of the part that is gripped is less than 10 mm in the direction of removal, 
30 N. 
The push force is applied by test probe 11 of IEC 61032 . 
The pull force is applied by a suitable means, such as a suction cup, so that the test results are 
not affected. While the force is being applied, the test fingernail of Figure 7 is inserted in any 
aperture or joint with a force of 10 N. The fingernail is then slid sideways with a force of 10  N 
but is not twisted or used as a lever.  
If the shape of the part is such that an axial pull is unlikely, the pull force is not applied but the 
test fingernail is inserted in any aperture or joint with a force of 10  N and is then pulled for 10  s 
by means of the loop with a force of 30 N in the direction of removal.  
If the part is likely to be twisted, the following torque is applied at the same time as the pull or push force:  
– 2 Nm, for major dimensions up to 50  mm; 
– 4 Nm, for major dimensions over 50 mm. IEC 60335- 1:2020 © IEC 2020 – 77 –          This torque is also applied when the test fingernail is pulled by means of the loop.  
If the projection of the part which is gripped is less than 10 mm, the torque is reduced by 50 %. 
Parts shall remain in the locked position and not become detached.  
22.12  Handles, knobs, grips, levers and parts providing a similar function shall be fixed in a 
reliable manner so that they will not work loose in normal use if loosening could result in a 
hazard , including a choking hazard . If these parts are used to indicate the position of switches 
or similar components, it shall not be possible to remove or fix them incorrectly if this could 
result in a hazard. The requirement concerning the choking hazard does not apply to appliances 
intended for commercial use.  
Sealing compound and similar materials, other than self -hardening resins, shall not be used to 
prevent loosening.  
Compliance is checked by inspection, by manual test and by trying to remove the part by applying an axial force of : 
– 15 N, if an axial pull is unlikely to be applied in normal use;  
– 30 N, if an axial pull is likely to be applied in normal use.  
The force is applied for 1  min. 
If the part is removed and can be contained within the small parts cylinder in Figure 13, its 
loosening is considered to result in a choking hazard.  
22.13  Appliances shall be constructed so that when handles are gripped in normal use, contact 
is unlikely between the operator's hand and parts having a temperature rise exceeding the value 
specified in Table 3 for handles which are held for short periods only in normal use.  
Compliance is checked by inspection and, if necessary, by determining the temperature rise.  
22.14  Appliances shall have no ragged or sharp edges, other than those necessary for the 
functioning of the appliance, which could create a hazard for the user in normal use or during user mainte nance . 
Pointed ends of self -tapping screws or other fasteners shall be located so that they are unlikely 
to be touched by the user in normal use or during user maintenance . 
Compliance is checked by inspection.  
22.15  Storage hooks and similar devices for flexible  cords shall be smooth and well -rounded.  
Compliance is checked by inspection.  
22.16  Automatic cord reels shall be constructed so that they do not cause : 
– undue abrasion or damage to the sheath of the flexible cord;  
– breakage of conductor strands;  
– undue wear of contacts.  
Compliance is checked by the following test, which is carried out without passing current through the flexible cord.   – 78 – IEC 60335- 1:2020 ©  IEC 20 20        Two- thirds of the length of the cord is unreeled. If the withdrawable length of the cord is less 
than 225  cm, the cord is unreeled so that a length of 75 cm remains on the reel. An additional 
length of 75  cm of the cord is then unreeled and pulled in a direction so that the greatest 
abrasion occurs to the sheath, taking into account the normal position of use of the appliance. 
Where th e cord leaves the appliance, the angle between the axis of the cord during the test and 
the axis of the cord when it is unreeled without substantial resistance is approximately 60°. The 
cord is allowed to be recoiled by the reel.  
If the cord does not recoi l at the angle of 60°, this angle is adjusted to the maximum that will 
allow recoil. 
The test is carried out 6 000 times at a rate of approximately 30 times per minute or at the 
maximum rate allowed by the construction of the cord reel if this is less.  
NOT E T he test can be interrupted to allow the cord to cool.  
After this test, the cord and cord reel are inspected. In case of doubt the cord is subjected to the electric strength test of 16.3, a test voltage of 1 000 V being applied between the conductors 
of the cord connected together and metal foil wrapped around the cord.  
22.17  Spacers intended to prevent the appliance from overheating walls shall be fixed so that 
it is not possible to remove them from the outside of the appliance by hand or by means of a screwdriver or a spanner.  
Compliance is checked by inspection and by manual test.  
22.18  Current -carrying parts and other metal parts, the corrosion of which could result in a 
hazard, shall be resistant to corrosion under normal conditions of use.  
The requirement is not applicable to parts made from stainless steel, plated steel and similar corrosion -resistant alloys.  
Compliance is checked by verifying that after the tests of Clause  19, the relevant parts show 
no sign of corrosion.  
NOTE   Compatibility of the materials of terminals and the effect of heating can influence corrosion.  
22.19  Driving belts shall not be relied upon to provide the required level of insulation unless 
they are constructed to prevent inappropriate replacement.  
Compliance is checked by inspection.  
22.20  Direct contact between live parts and thermal insulation shall be effectively prevented 
unless such material is non- corrosive, non- hygroscopic and non- combustible. 
The requirement is not applicable to glass -wool thermal insulation . 
NOTE  Non-impregnated slag -wool is an example of corrosive thermal insulation.  
Compliance is checked by inspection and, if necessary, by appropriate tests.  
22.21  Wood, cotton, silk, ordinary paper and similar fibrous or hygroscopic material shall not 
be used as insulation, unless impregnated. This requirement does not apply: 
– to magnesium oxide and mineral ceramic fibres used for the electrical insulation of heating 
elements ; 
– insulating material where the interstices between the fibres of the material are substantially filled with a suitable insulant.  IEC 60335- 1:2020 © IEC 2020 – 79 –          Compliance is checked by inspection.  
22.22  Appliances shall not contain asbestos.  
Compliance is checked by inspection.  
22.23  Oils containing polychlorinated biphenyl (PCB) shall not be used in appliances.  
Compliance is checked by inspection.  
22.24  Bare heating elements, other than those in class III appliances  or class III 
constructions that do not contain live parts , shall be supported so that the heating conductor 
is unlikely to come into contact with accessible metal parts  if they rupture.  
Compliance is checked by inspection after cutting the heating conductor in the most 
unfavourable place. No force is applied to the conductor after it has been cut.  
22.25  Appliances shall be constructed so that sagging heating conductors cannot come into 
contact with accessible metal parts . This requirement does not apply : 
– to class III appl iances or parts of  class III constructions that do not contain live parts ; 
– where a core is provided that effectively prevents the heating conductor from sagging; or  
– where supplementary insulation  is provided to prevent the heating conductor from 
contacting  accessible metal parts . 
Compliance is checked by inspection.  
22.26  Appliances having parts of class III construction  shall be constructed so that the 
insulation between parts operating at safety extra- low voltage  and other live parts  complies 
with the requirements for double insulation or reinforced insulation. 
Compliance is checked by the tests specified for double insulation  or reinforced insulation. 
22.27  Parts connected by protective impedance  shall be separated by double insulation  or 
reinforced insulation. 
Compliance is checked by the tests specified for double insulation  or reinforced insulation. 
22.28  For class II appliances  connected in normal use to the gas mains or to the water mains, 
metal pa rts conductively connected to the gas pipes or in contact with the water shall be 
separated from live parts  by double insulation or reinforced insulation. 
Compliance is checked by inspection.  
22.29  Class II appliances  intended to be permanently connected to fixed wiring shall be 
constructed so that the required degree of access to live parts  is maintained after installation.  
NOTE  The protection against access to live parts can be affected, for example, by the installation of metal conduits 
or cables provided with a metal sheath.  
Compliance is checked by inspection.  
22.30  Parts of class II construction  which serve as supplementary insulation or reinforced 
insulation, and which could be omitted during reassembly after servicing, shall be: 
– fixed so that they cannot be removed without being seriously damaged ; or  – 80 – IEC 60335- 1:2020 ©  IEC 20 20        – constructed so that they cannot be replaced in an incorrect position and if they are omitted, 
the appliance is rendered inoperable or manifestly incomplete.  
NOTE  Servicing includes replacement of components such as supply cords  except in appliances having a Type  Z 
attachment  and switches.  
Compliance is checked by inspection and by manual test.  
22.31  Neither clearances  nor creepage distances over supplementary insulation  and 
reinforced insulation shall be reduced below the values specified in Clause  29 as a result of 
wear.  
If a part, such as a wire, screw, nut or spring, becomes loose or falls out of position, neither clearances nor creepage distances between live parts and accessible parts shall be 
reduced below the values specified for supplementary insulation . This requirement does not 
apply if:  
– parts are fixed by means of screws or nuts and locking washers provided that these scr ews 
or nuts are not required to be removed during the replacement of the supply cord  or other 
servicing;  
– short rigid wires remain in position when the terminal screw is loosened;  
– parts are held in place with two independent fixings that are not expected to  become loose 
at the same time;  
– wires connected by soldering are held in place near the terminals independently of the solder;  
– wires connected to terminals have an additional fixing provided near the terminal, so that in the case of stranded conductors, th e fixing clamps both the insulation and conductor.  
With the appliance in its normal position of use, compliance is checked by inspection, by manual 
test and by measurement.  
22.32  Supplementary insulation and reinforced insulation  shall be constructed or protected 
so that the deposition of pollution resulting from wear of parts within the appliance does not reduce clearances  or creepage distances below the values specified in Clause  29. 
Parts of natural or synthetic rubber used as supplementary insulation shall be resistant to 
ageing or be located and dimensioned so that creepage distances are not reduced below the 
values specified in 29.2 , even if cracks occur.  
Ceramic material which is not tightly sintered, similar materials or beads alone shall not be used as supplementary insulation or reinforced insula tion. Ceramic and similar porous material 
in which heating conductors are embedded is considered to be basic insulation and not 
reinforced insulation. This requirement is not applicable to heating conductors in PTC heating 
elements . 
Compliance is checked by inspection and by measurement.  
If the rubber part has to be resistant to ageing, the following test is carried out.  
The part is suspended freely in an oxygen bomb, the effective capacity of the bomb being at 
least 10 times the volume of the part. The bomb is filled with oxygen not less than 97  % pure, 
to a pressure of 2,1 MPa  
± 0,07  MPa and maintained at a temperature of 70 °C ± 1 °C. 
WARNING  – The use of the oxygen bomb presents some danger unless handled with care. 
Precautions shall be taken to avoid the risk of explosion due to sudden oxidation.  
The part is kept in the bomb for 96  h. It is then removed from the bomb and left at room 
temperature  out of direct sunlight for at least 16  h. IEC 60335- 1:2020 © IEC 2020 – 81 –          The part is then examined and shall show no crack visible to the naked eye.  
In case of doubt, the following test is carried out to determine if ceramic material is tightly 
sintered.  
The ceramic material is broken into pieces that are immersed in a solution containing 1 g of 
fuchsine in each 100  g of methylated spir it. The solution is maintained at a pressure not less 
than 15 MPa for a period so that the product of the test duration in hours and the test pressure 
in megapascals is approximately 180.  
The pieces are removed from the solution, rinsed, dried and broken into smaller pieces.  
The freshly broken surfaces are examined and shall not show any trace of dye visible to the naked eye.  
22.33  Conductive liquids that are or may become accessible in normal use and conductive 
liquids that are in contact with unearthed accessib le metal parts  shall not be in direct contact 
with live parts or unearthed metal parts that are separated from  live parts by basic insulation  
only. 
Electrodes shall not be used for heating liquids.  
For class II construction , conductive liquids that are or may become accessible in normal use 
and conductive liquids that are in contact with unearthed accessible metal parts shall not be 
in direct contact with basic insulation  or reinforced insulation  unless the reinforced 
insula tion consists of at least 3 layers.  
For class II construction , conductive liquids which are in contact with live parts  shall not be 
in direct contact with reinforced insulation unless the reinforced insulation  consists of at 
least 3 layers.  
An air layer shall not be used as basic insulation  or supplementary insulation in a double 
insulation system if it is likely to be bridged by leaking liquid.  
Compliance is checked by inspection.  
22.34  Shafts of operating knobs, handles, levers and similar parts shall not be li ve unless the 
shaft is inaccessible when the part is removed.  
Compliance is checked by inspection and by applying the test probe as specified in 8.1  after 
removal of  the part even with the aid of a tool. 
22.35  For other than class III  constructions , handles, levers and knobs that are held or 
actuated in normal use shall not become live in the event of a failure of basic insulation . 
If these handles, levers and knobs are of metal and if their shafts or fixings are likely to become 
live in the event of a failure of basic insulation, they shall be adequately covered by insulating 
material or their accessible parts  shall be separated from their shafts or fixings by 
supplementary insulation . 
For stationary appliances  and cordless appliances , this requirement does not apply to handles, 
levers and knobs, other than those of electrical components, provided that they are reliably connected to an earthing terminal or earthing contact or separated from live parts  by earthed 
metal.  
NOTE  A cordless appliance is an appliance that is connected to the supply only when placed on its associated 
stand.  
Compliance is checked by inspection and if necessa ry by the relevant tests.   – 82 – IEC 60335- 1:2020 ©  IEC 20 20        Insulating material covering  metal handles, levers and knobs shall withstand the electric 
strength test of 16.3  specified for supplementary insulation . 
22.36  For appliances other  than class III  appliances , handles which are continuously held in 
the hand in normal use shall be constructed so that when gripped in normal use, the operator's 
hand is not likely to touch metal parts unless they are separated from live parts by double 
insulation or reinforced ins ulation. 
Compliance is checked by inspection.  
22.37  For class II appliances, capacitors shall not be connected to accessible metal parts  
and their casings, if of metal, shall be separated from accessible metal parts by 
supplementary insulation . 
This requirement does not apply to capacitors complying with the requirements for protective 
impedance  specified in 22.42. 
Compliance is checked by inspection and by the relevant tes ts. 
22.38  Capacitors shall not be connected between the contacts of a thermal cut -out. 
Compliance is checked by inspection.  
22.39  Lampholders shall be used only for the connection of lamps.  
Compliance is checked by inspection.  
22.40  Motor- operated appliances  and combined appliances  which are intended to be moved 
while in operation, or which have accessible moving parts , shall be fitted with a switch to 
control the motor. The actuating member of this switch shall be easily visible and accessible.  
Unless the appliance can operate continuously, automatically or remotely  without giving rise to 
a hazard, a ppliances for remote operation shall be fitted with a switch for stopping the 
operation  of the appliance.  The actuating member of this switch shall be easily visible a nd 
accessible.  
NOTE  Examples of appliances that can operate continuously, automatically or remotely  without giving rise to a 
hazard are fans, storage water heaters, air conditioners, refrigerators  and drives for awnings, windows, doors, gates 
and shutters . 
Compliance is checked by inspection.  
22.41  Appliances shall not incorporate components, other than lamps, containing mercury.  
Compliance is checked by inspection . 
22.42  Protective impedance  shall consist of at least two separate components. If any one of 
the components is short -circuited or open- circuited, the values specified in 8.1.4 shall not be 
exceeded.  
Component impedances shall be unlikely to change significantly during t he lifetime of the 
appliance.  
Compliance is checked by inspection and by measurement and if necessary, for resistors and 
capacitors by the following tests.  IEC 60335- 1:2020 © IEC 2020 – 83 –          Resistors are checked by the test of 14.2 a) in IEC  60065:2014 and capacitors are checked by 
the tests for class Y capacitors in IEC 60384- 14:2013 including IEC 60384 -14:2013/AMD1:2016  
appropriate to the rated voltage  of the appliance.  
22.43  Appliances which can be adjusted for different voltages shall be constructed so t hat 
accidental changing of the setting is unlikely to occur.  
Compliance is checked by manual test.  
22.44  Appliances shall not have an enclosure that is shaped or decorated like a toy.  
NOTE 1  Examples of such enclosures are those representing animals, characters,  persons or scale models.  
The requirement  is not applicable to appliances  where there is a toy shaped like the appliance.  
NOTE 2  An example of a toy shaped like an appliance is a toy refrigerator . 
Compliance is checked by inspection.  
22.45  When air is used as reinforced insulation, the appliance shall be constructed so that 
clearances  cannot be reduced below the values specified in 29.1.3 due to deformation as a 
result of an external force applied to the enclosure.  
Compliance is checked by inspection and by  applying a force of 30  N to accessible surfaces . 
22.46  If programmable protective electronic circuits  are used to ensure compliance with this 
standard, the  software shall contain measures to control the fault/error conditions specified in 
Table  R.1. 
These requirements are not applicable to software used for functional purpose or for compliance 
with Clause  11. 
Compliance is checked by evaluating the software in accordance with the relevant requirements of normative Annex  R. 
If the software is modified, the evaluation and relevant tests are repeated if the modification influen ces the results of the test involving protective  electronic circuits. 
22.47  Appliances intended to be connected to the water mains shall withstand the water 
pressure expected in normal use.  
Compliance is checked by connecting the appliance to a water supply having a static pressure equal to twice the maximum inlet water pressure or 1,2 MPa, whichever is higher, for a period 
of 5 min. 
There shall be no leakage from any part, including any inlet water hose.  
22.48  Appliances intended to be connected to the water mains shall be constructed to prevent 
back -siphonage of non -potable water into the water mains.  
Compliance is checked by the relevant tests of IEC 61770.  
22.49  For remote operation , the duration of operation shall be set before the appliance can 
be started unless the appliance switches off automatically at the end of a cycle or it can operate 
continuously without giving rise to a hazard.  
Compliance is checked by inspection.   – 84 – IEC 60335- 1:2020 ©  IEC 20 20        NOTE  For appliances such as ovens, the duration of operation has to be set before the appliance can be started. 
Washing machines and dishwashers are examples of appliances that switch off automatically at the end of a cycle. 
Fans, storage water heaters, air conditioners and refrigerators are examples of appliances that can operate 
continuously without giving rise to a hazard.  
22.50  Controls incorporated in the appliance, if any, shall take priority over controls actuated 
by remote operation . 
Compliance is checked by inspection and by appropriate tests if necessary.  
22.51  A control on the appliance shall be manually adjusted to the setting for remote operation  
before the appliance can be operated in this mode. There shall be a visual indication on the 
appliance showing that the appliance is adjusted for remote operation . The manual setting and 
the visual indication of the remote mode are not necessary on appliances that can: 
– operate continuously ; or 
– operate automatically ; or  
– be operated remotely ; 
without giving rise to a hazard.  
Compliance is checked by inspection.  
NOTE  Examples of appliances that can operate continuously, automatically or remotely  without giving rise to a 
hazard are fans, storage water heaters, air conditioners, refrigerators  and drives for awnings, windows, doors, gates 
and shutters . 
22.52  Socket -outlets on appliances accessible to the user shall be in accordance  with the 
socket -outlet system used in the country in which the appliance is sold.  
Compliance is checked by inspection.  
22.53  Class II appliances and class III appliances  that incorporate functionally earthed parts 
shall have at least double insulation or reinforced insulation between live parts  and the 
functionally earthed parts.  
Compliance is checked by inspection and test.  
22.54  Button cells  and batteries designated R1 shall not be accessible without the aid of a 
tool unless the cover of their compartment can only be opened after at least two independent 
movements have been applied simultaneously.  
Compliance is checked by inspection and by manual test.  
NOTE  Batteries are specified in IEC 60086 -2. 
22.55  Devices that are operated by the user to stop the intended function of the appliance, if 
any, shall be distinguished from other manual devices by means of shape, or size, or surface 
texture, or position. This requirement concerning position does not preclude use of a push on 
push off switch.  
An indication when the device has been operated shall be given by:  
– tactile feedback from the actuator or tactile feedback from the appliance such as stopping 
of the vibration on the body of the appliance or of a part of it; or  
– reduc tion in heat output; or  
– audible and visible feedback.  IEC 60335- 1:2020 © IEC 2020 – 85 –          The sound of the motor or sound of an actuator switching from on to off is considered as an 
audible feedback. A switch with a stable off -position  different from the on -position is 
considered visual and tactile feedback.  The force feedback from the actuator when operating it 
is considered to be tactile feedback.  
Compliance is checked by inspection and by manual test.  
22.56  Detachable power supply part  shall be provided with the part of class III construction  
of the appliance.  
Compliance is checked by inspection.  
22.57  The properties of non- metallic materials shall not degrade from exposure to UV -C 
radiation generated from UV sources provided for microbiological control within the appliance such that they no longer comply with this standard. This requirement does not apply to glass, 
ceramics or similar materials.  
Compliance is checked by the conditioning and tests of normative Annex  T. 
22.58  Appliances connected to the supply mains by an appliance inlet, shall be provided with 
a cord set or a connector for attachment to a suitable flexible cord.  
The requirement is not applicable to: 
– appliances  connected to the supply mains by an appliance  inlet complying with the standard 
sheets of IEC 60320- 3; 
– single phase appliances having a  rated current exceeding 16  A and that are connected to 
the supply mains by an appliance inlet complying with the standard sheets of IEC 60309- 2; 
– multi -phase appliances  connected to the supply mains by an appliance inlet complying with 
the standard sheets of IEC 60309- 2; 
Compliance is checked by inspection.  
22.59  Protective extra -low voltage circuits shall be separated by at least supplementary 
insulation from circuits operating at safety extra- low voltage. 
NOTE  Supplementary insulation is not required between protective extra- low voltage circuits . 
Compliance is checked by inspection and the tests for supplementary insulation. 
22.60  Functional earthing terminals and functional earthing contacts shall not be connected to 
the neutral terminal.  
Compliance is checked by inspection.  
22.61  Appliance outlets complying with the standard sheets in IEC 60320- 3 accessible to the 
user and socket -outlets accessible to the user : 
– that are incorporated in appliances connected to the supply mains; and 
– that operate at rated voltage  
shall be single -phase with a current rating not exceeding 16  A. 
Appliance outlets accessible to the user, other than those intended to supply accessories 
supplied with the appliance and socket -outlets accessible to the user shall be protected by one 
of the following protective devices , having a current rating not exceeding the current rating of 
the appliance outlet or socket -outlet:   – 86 – IEC 60335- 1:2020 ©  IEC 20 20        – a circuit breaker for equipment complying with IEC 60934;  
– a non -user replaceable fuse- link. 
The protective device  shall be placed behind a non- detachable cover . The actua ting member 
of the circuit breaker may be accessible.  
The current rating of appliance outlets and socket -outlets marked with the outlet load  in watts, 
is obtained from the marked outlet load  divided by the rated voltage. 
Compliance is checked by inspection.  
22.62  Remote communication through public networks shall not impair compliance with this 
standard.  
The requirement is only applicable to:  
a) remote communication that includes the download of software or the transmission  of data 
that includes:  
– measures according to normative Annex  R necessary for compliance with 22.46; or 
– means necessary for compliance with Clauses 8 to 32 of this standard.  
NOTE 1  Examples of such means are constants, algorithms, timers or a downloaded software or parameter set 
which regulates or limits the maximum normal temperature rises in Clause  11. 
NOTE 2  Examples of means which do not affect Clauses 8 to 32 of this standard are the change of speed setting 
of a range hood fan, operation of a drive to open or close a driven part or change of operational setting of an air 
conditioner, such as fan speed, heating and cooling temperatures and louver movement.  
b) remote communication  that includes the download of software  or the transmission  of data, 
that only affects that part of the software that is not covered by the above case a), but where 
compliance with this standard may be impaired due to improper separation or partitioning 
from the software or data in the above case a).  
The requirement is not applicable to appliances : 
– where all measures to comply with this standard are independent of software;  
– using remote communication through public networks for the send- only  transmission of 
data;  or 
– that only provide event driven messages  or push remote monitoring.  
Compliance is checked by inspection of the product, inspection of the technical documentation, 
and by the requirements and tests in normative Annex  U. 
23 Internal wiring  
23.1  Wireways shall be smooth and free from sharp edges.  
Wires shall be protected so that they do not come into contact with burrs, cooling fins or similar edges which may cause damage to their insulation.  
Holes in metal through which insulated wires pass shall have smooth well -rounded surfaces or 
be provided with bushings.  
Wiring shall be effectively prevented from coming into contact with moving parts.  
Compliance is checked by inspection.  IEC 60335- 1:2020 © IEC 2020 – 87 –          23.2  Beads and similar ceramic insulators on live wires shall  be fixed or located so that they 
cannot change their position or rest on sharp edges. If beads are inside flexible metal conduits, 
they shall be contained within an insulating sleeve, unless the conduit cannot move in normal use. 
Compliance is checked by inspection and by manual test.  
23.3  Different parts of an appliance that can move relative to each other in normal use or 
during user maintenance  shall not cause undue stress to electrical connections and internal 
conductors, including those providing earthing continuity. Flexible metallic tubes shall not cause damage to the insulation of the conductors contained within them. Open -coil springs shall not 
be used to protect the wiring. If a coiled spring, the turns of which touch one another, is used 
for this purpose, there shall be an adequate insulating lining, such as the sheath of a flexible 
cord complying with IEC 60227 , IEC 60245 or IEC 62821 , in addition to the insulation of the 
conductors.  
Compliance is checked by inspection and by the following test. 
If flexing occurs in normal use, the appliance is placed in the normal position of use and is 
supplied at rated voltage  and operated under normal operation . 
The movable part is moved backwards and forwards, so that the conductor is flexed through the largest angle allowed by the construction, the rate of flexing being 30 per minute. The number of flexings is : 
– 10 000, for conductors flexed during normal use;  
– 100, for conductors flexed during user maintenance. 
NOTE  A flexing is one movement, either backwards or forwards.  
The appliance shall not be damaged to the extent that compliance with this standard is impaired 
and it shall be fit for further use. In particular, the wiring and its connections shall withstand the electric strength test of 16.3, the test voltage being reduced to 1  000 V and applied between 
live parts  and accessible metal parts  only.  In addition, not more than 10 % of the strands of 
any conductor of the internal wiring between the main part of the appliance and the movable part shall be broken. However, if the wiring supplies circuits that consume no more than 15 W, 
then no more than 30 % of the strands shall be br oken.  
23.4  Bare internal wiring shall be rigid and fixed so that, in normal use, clearances or 
creepage distances cannot be reduced below the values specified in Clause  29. 
Compliance is checked during the tests of 29.1  and 29.2 . 
23.5  A single layer of internal wiring insulation shall not be used to provide reinforced 
insulation. 
For class II construction , the sheath of a cord complying with IEC 60227 or IEC 60245 or 
IEC 62821 may provide supplementary insulation . 
Insulation of s ingle layer internal wiring that is subjected to the supply mains voltage shall 
withstand the electrical stress likely to occur in normal use.  
Compliance is checked by inspection  and as follows.  
The insulation of single layer internal wiring shall be elect rically equivalent to the basic 
insulation  of cords complying with IEC 60227 or IEC 60245  or IEC 62821  or shall  comply with 
the following electric strength test. If the basic insulation  of the conductor does not fulfil one 
of these conditions, the conductor is considered to be bare.   – 88 – IEC 60335- 1:2020 ©  IEC 20 20        A voltage of 2 000 V is applied for 15 min between the conductor and metal foil wrapped around 
the insulation. There shall be no breakdown.  
23.6  When sleeving is used as supplementary insulation on internal wiring, the sleeving 
shall be retained in position by clamping at both ends  or be such that it can only be removed 
by breaking or cutting.  
Compliance is checked by inspection and by manual test.  
23.7  Conductors identified by the colour combination green/yellow shall only be used for 
earthing conductors.  
Compliance is checked by inspection.  
23.8  Aluminium wires shall not be used for internal wiring. 
The requirement does not apply to windings.  
Compliance is c hecked by inspection.  
23.9  Stranded conductors shall not be consolidated by soldering where they are subjected to 
contact pressure, unless the contact pressure is provided by spring terminals.  
The requirement does not apply to the soldered tip of a stranded con ductor.  
Compliance is checked by inspection.  
23.10  The insulation and sheath of internal wiring, incorporated in external hoses for the 
connection of an appliance to the water mains, shall be at least equivalent to that of light 
polyvinyl chloride sheathed flexible cord (code designation 60227 IEC 52).  
Compliance is checked by inspection  and by the tests specified in  Table 6 of IEC 60227 -5:2011 
reference numbers 1 and 2 . 
24 Components  
24.1  Components shall comply with the safety requirements specified in the relevant IEC 
standards as far as they reasonably apply.  
Compliance with the IEC standard for the relevant component does not necessarily ensure compliance with the requirements of this standard.  
Motors are not required to comply with IEC 60034- 1. They are tested as part of the appliance 
according to this standard.
 
Relays shall be tested as part of the appliance according to this standard. They may be 
alternatively tested to IEC  60730-1 :2013 including IEC  60730-1:2013/AMD1:2015, in which 
case they must also meet the additional requirements in IEC 60335- 1. 
Unless otherwise specified, the requirements of Clause  29 of this standard apply between live 
parts  of components and accessible parts  of the appliance.  Unless otherwise specified, 
components may comply with the requirements for clearances  and creepage distances for 
functional insulation as specified in the relevant component standard.  IEC 60335- 1:2020 © IEC 2020 – 89 –          Unless otherwise specified, the requirements  of 30.2 of this standard apply to parts of non-
metallic material in components including parts of non- metallic material supporting current -
carrying connections inside components.  
Components that  have not been previously tested and shown to comply with the IEC standard 
for the relevant component are tested according to the requirements of 30.2  of this standard.  
Components that have been previously tested and shown to comply with the resistance to fire 
requirements in the IEC standard for the relevant component need not be retested provided 
that: 
– the seve rity specified in the component standard is not less than the severity specified in 
30.2 of this standard, and  
– unless the pre- selection alternatives in 30.2 are used, the test report for the component 
states  the values of tE and ti as required by IEC 60695-2- 11:2014 . 
If the above two conditions are not satisfied, the component is tested as part of the appliance.  
NOTE  1 There are two levels of severity specified for appliances for which 30.2.3 is applicable.  
Power electronic converter circuits are not required to comply with IEC 62477- 1. They are 
tested as part of the appliance according to this standard.  
Unless components have been previously tested and found to comply with the relevant 
IEC standard for the number of cycles specified, they are tested in accordance with 24.1.1  
to 24.1.9. For components mentioned in 24.1.1  to 24.1.9, no additional tests specified in the 
relevant IEC  standard for the component are necessary other than those specified in 24.1.1 to 
24.1.9. 
Components that have not been separately tested and found  to comply with the relevant IEC 
standard and components that are not marked or not used in accordance with their marking are 
tested in accordance with the conditions occurring in the appliance, the number of samples 
being that required by the relevant standard.  
NOTE  2 For automatic controls, marking includes documentation and declaration as specified in Clause 7 of 
IEC 60730-1 :2013/AMD1:2015. 
Lampholders and starterholders that have not been previously tested and found to comply with the relevant IEC standard are tested as a part of the appliance and shall additionally comply 
with the gauging and interchangeability requirements of the relevant IEC standard under the conditions occurring in the appliance. Where the relevant IEC standard specifies these gauging 
and interchangeability requirements at elevated temperatures, the temperatures measured 
during the tests of Clause  11 are used.  
Unless they are specifically m entioned in the text of this standard, there are no additional tests 
specified for nationally standardized plugs such as those detailed in IEC  TR 60083 or 
connectors or plug connectors complying with the standard sheets of IEC 60320- 3 or 
connectors complyi ng with the standard sheets of IEC 60309 -2. 
When an IEC standard does not exist for a component, there are no additional tests specified.  
24.1.1  The relevant standard for capacitors likely to be permanently subjected to the supply 
voltage and used for radio interference suppression or for voltage dividing is IEC 60384 -14:2013 including IEC 60384- 14:2013/AMD1:2016.  
Capacitors likely to be permanently subjected to the supply voltage are capacitors incorporated in appliances : 
– for which 30.2.3 is applicable; or   – 90 – IEC 60335- 1:2020 ©  IEC 20 20        – for which 30.2.2 is applicable, unless the capacitor is disconnected from the supply mains 
by an on -off switch. This switch shall provide all -pole disconnection if the capacitor is 
connected to earth.  
If the capacitors have to be tested, they are tested in accordance with normative Annex  F. 
24.1.2  The relevant standard for transformers in associated switch mode power supplies is 
Annex  BB of IEC 61558 -2-16:2009 including IEC 61558-2- 16:2009/AMD1:2013 . Clause 26  of 
IEC 61558 -1:2017  and Annex  H of IEC 61558-1 :2017  are not applicable.  
The relevant standard for safety isolating transformers  is IEC 61558-2-6 :2009 . If they have 
to be tested, they are tested in accordance with normative Annex  G. 
24.1.3  The relevant standard for switches is IEC 61058 -1:2016 . The number of cycles of 
operation declared for 7.4  of IEC 61058 -1:201 6 shall be at least 10 000. If they have to be 
tested, they are te sted in accordance with  normative  Annex  H. 
The number of operating cycles for switches need not be declared for 7.4 if the appliance meets 
the requirements of this standard when they are rendered inoperative. 
If the switch operates a relay or contactor, the complete switching system is subjected to the 
test. 
If the switch only operates a motor starting relay complying with IEC 60730-2- 10 with the 
number of cycles of operation declared for 6.10  and 6.11  of IEC 60730-1 :2013 including 
IEC 60730 -1:2013/AMD1:2015  of at least 10 000 cycles, the complete switching system need 
not be tested.  
24.1.4  The relevant standard for automatic controls is IEC  60730 -1:2013 including 
IEC 60730 -1:2013/AMD1:2015 together with the relevant part 2.  
The number of cycles of operation declared for 6.10  and 6.11 of IEC 60730 -1:2013 including 
IEC 60730 -1:2013/AMD1:2015  shall not be less than the following:  
– thermostats  10 000  
– temperature limiters 1 000 
– self-resetting thermal cut -outs 300 
– voltage -maintained non- self-resetting thermal cut -outs   1 000 
– other non- self-resetting thermal cut -outs 30 
– timers  3 000 
– energy regulators  10 000  
The number of cycles of operation for automatic controls that operate during the test of 
Clause  11 need not be declared for 6.10  and 6.11 of IEC 60730- 1, if the appl iance meets the 
requirements of this standard when they are short -circuited  or rendered inoperative . 
If automatic controls have to be tested, they are also tested in accordance with Subclauses  11.3.5 to 11.3.8 and Clause 17 of IEC 60730 -1:2013 including 
IEC 60730 -1:2013/AMD1:2015  as type 1 controls.  The tests of Clauses 12, 13 and 14 of 
IEC 60730 -1:2013 including  IEC 60730-1 :2013/AMD1:2015  are not carried out before carrying 
out the test of Clause 17 . 
The ambient temperature during the test of Clause 17  of
  IEC 60730 -1:2013 including 
IEC 60730 -1:2013/AMD1:2015 is that occurring during the test of Clause  11 in the appliance, 
as specified in footnote b of Table 3. IEC 60335- 1:2020 © IEC 2020 – 91 –          Thermal motor protectors are tested in combination with their motor under the conditions 
specified in normative Annex  D. 
For water valves containing live parts and that are incorporated in external hoses for 
connection of an appliance to the water mains, the degree of protection provided by enclosures 
against harmful ingress of water declared for Subclause 6.5.2 of IEC 60730 -2-8: 2018  shall be 
IPX7.  
Thermal cut -outs  of the capillary type shall comply with the requirements for type 2.K controls 
in IEC 60730 -2-9:2015 including IEC 60730-2- 9:2015/AMD1:2018 . 
24.1.5  The relevant standard for appliance couplers is IEC 60320- 1. However, for appliances 
classified higher than IPX0, the relevant standard is IEC 60320 -2-3. 
24.1.6  The relevant standard for small lampholders similar to E10 lampholders is IEC 60238, 
the requirements for E10 lampholders being applicable. However, they need not accept a lamp 
with an E10 cap complying with the current edition of standard sheet 7004- 22 of IEC 60061- 1. 
24.1.7  If the remote operation of the appliance is via a telecommunication network, the 
relevan t standard for the telecommunication interface circuitry in the appliance is IEC 62151.  
24.1.8  The relevant standard for thermal links  is IEC 60691. Thermal links  that do not 
comply with IEC  60691 are considered to be an intentionally weak part  for the purposes of 
Clause  19. 
24.1.9  Contactors and relays, other than motor starting relays, are tested as part of the 
appliance. However, they are also tested in accordance with Clause 17 of IEC 60730-1 :2013 
including IEC 60730- 1:2013/AMD1:2015 under the maximum load conditions occurring in the 
appliance for at least the number of cycles of operation in 24.1.4 selected according to the 
contactor or relay function in the appliance.  
24.1.10  Lamps and lamp systems that have not been previously tested and found to comply 
with the exempt group classification of IEC 62471 :2006 general lighting systems (GLS) 
regarding actinic ultraviolet hazard (ES) and near- UV hazard (EUVA) are tested as a part o f the 
appliance and shall comply with the requirements of Clause  32 under the conditions occurring 
in the appliance . 
Unless otherwise specified, the following components are considered to comply with the exempt group classification of IEC 62471 :2006 regarding actinic ultraviolet hazard (E
S) and near -UV 
hazard (EUVA): 
– visible light indicators;  
– infrared sources used for signalling or communication;  
– seven- segment indicators;  
– liquid -crystal displays;  
– organic LED displays (OLED);  
– plasma displays. 
24.1.11  For cord sets required to be provided with the appliance, the relevant standard is 
IEC 60799. Cord sets with cords complying to IEC 62821- 3 are allowed.  
24.2  Appliances shall not be fitted with: 
– switches , automatic controls , power supplies and the like  in flexible cords;  
– devices that cause the protective device  in the fixed wiring to operate in the event of a 
fault in the appliance;   – 92 – IEC 60335- 1:2020 ©  IEC 20 20        – thermal cut -outs  that can be reset by a soldering operation, unless the solder has a melting 
point of at least 230  °C. 
Compliance i s checked by inspection.  
24.3  Switches intended to ensure all -pole disconnection  of stationary appliances, as 
required in 22.2, shall be directly connected to the supply terminals and shall have a contact 
separation in all poles, providing full disconnection under overvoltage category III conditions.  
NOTE 1  Full disco nnection is contact separation of a pole to ensure the equivalent of basic insulation, in 
accordance with IEC 6 1058-1 :2016, between the supply mains and those parts that are intended to be disconnected.  
NOTE 2  Rated impulse voltages for overvoltage categor ies are given in Table 15.  
Compliance is checked by inspection and by measurement.  
24.4  Plugs and socket -outlets for extra- low voltage  circuits, and those used as terminal 
devices for heating elements, shall not be interchangeable with plugs and socket -outlets listed 
in IEC  TR 60083 or IEC  60906- 1 or with connectors, appliance inlets, plug connectors and 
appliance outlets complying with the standard sheets of IEC 60320-3. 
Compliance is checked by inspection.  
24.5  Capacitors in auxiliary windings of motors shall be marked with their voltage rating and 
their rated capacitance and shall be used in accordance with these markings.  
Compliance is checked by inspection and by the appropriate tests. In addition, for capacitors 
connected in series with a motor winding, it is verified that, when the appliance is supplied at 1,1 times rated voltage  and under minimum load, the voltage across the capacitor does not 
exceed 1,1 times its  voltage rating . 
24.6  The working voltage of motors directly connected to the supply mains and having basic 
insulation that is inadequate for the rated voltage  of the appliance, shall not exceed 42 V. In 
addition, they shall comply with the requirements of normative Annex  I. 
Compliance is checked by measurement and by the tests of normative  Annex  I. 
24.7  Detachable hose -sets  for the connection of appliances to the water mains shall comply 
with IEC  61770. They shall be supplied with the appliance.  
Appliances intended to be permanently connected to the water mains shall not be connected 
by a detachable hose -set. 
NOTE  Examples of appliances that are considered not intended to be permanently connected to the water mains 
are household appliances such as  dishwashers, washing machines, tumble dryers, refrigerators, icemakers, steam 
ovens and the like.  
Compliance is checked by inspection.  
24.8  Motor running capacitors in appliances for which 30.2.3 is applicable and that are 
permanently connected in series with a motor winding shall not cause a hazard in the event of a capacitor failure.  
The requirement is considered to be met by one or more of the following conditions:  
– the capacitors are of class of safety protection  S2 or S3  according to IEC  60252-1 :2010 
including IEC 60252- 1:2010/AMD1:2013; 
– the capacitors are housed within a metallic or ceramic enclosure that will prevent the 
emission of flame or molten material resulting from failure of the capacitor;  IEC 60335- 1:2020 © IEC 2020 – 93 –          NOT E The enclosure can have an entry or exit hole for the wiring connecting the capacitor to the motor. 
– the distance of separation of the outer surface of the capacitor to adjacent non- metallic parts 
exceeds 50  mm; 
– adjacent non -metallic parts within 50 mm of the outer surface of the capacitor withstand the 
needle -flame test of normative Annex  E; 
– adjacent non -metallic parts within 50  mm of the outer surface of the capacitor are classified 
as at least V -1 according to IEC 60695 -11-10, provided that the test sample used for the 
classification was no thicker than the relevant part of the appliance.  
For capacitors complying with IEC 60252-1 :2010 including IEC 60252- 1:2010/AMD1:2013, the 
damp heat test severity parameters for 5.14  of IEC 60252 -1:2010 including IEC  60252-
1:2010/AMD1:2013 shall be: 
– temperature 40 °C ± 2 °C at a relative humidity of 93 % ± 3 %; 
– duration 21 days.  
Compliance is checked by inspection, measurement or the appropriate flammability requirement . 
25 Supply connection and external flexible cords  
25.1  Appliances, other than those intended to be permanently connected to fixed wiring, shall 
be provided with one of the following means for connection to the supply mains:  
– supply cord  fitted with a plug , the current rating and voltage rating of the plug being not 
less than the corresponding ratings of its associated appliance ; 
– an appliance inlet having at least the same degree of protection against moisture as required 
for the appliance;  
– pins for insertion into socket -outlets.  
Compliance is checked by inspection.  
25.2  Appliances, other than stationary appliances for multiple supply, shall not be provided 
with more than one means  of connection to the supply mains. Stationary appliances for 
multiple supply may be provided with more than one means of connection provided that the 
relevant circuits are adequately insulated from each other.  
NOTE  1 For example, a multiple supply may be required for appliances supplied with day and night tariffs.  
Compliance is checked by inspection and by the following test. 
A voltage of 1 250 V of substantially sinusoidal waveform and having a frequency of 50 Hz or 
60 Hz is applied for 1  min between each  means of connection to the supply mains.  
NOTE  2 This test can be combined with that of 16.3. 
During this test, no breakdown shall occur.  
25.3  Appliances intended to be permanently connected to fixed wiring shall be provided with  
one of the following means for connection to the supply mains:  
– cord anchorage and a set of terminals allowing the connection of a flexible cord;  
– a fitted supply cord; 
– a set of supply leads  accommodated in a suitable compartment;  
– a set of terminals allowing the connection of cables of fixed wiring having the nominal cross -
sectional areas specified in 26.6 ;  – 94 – IEC 60335- 1:2020 ©  IEC 20 20        – a set of terminals and cable entries,  conduit entries, knock -outs or glands, which allow the 
connection of the appropriate types of cable or conduit.  
Appliances intended to be permanently connected to fixed wiring that are provided with : 
– a set of terminals allowing the connection of cables of  fixed wiring having the nominal cross -
sectional areas specified in 26.6 ; or 
– a set of terminals and cable entries, conduit entries, knock -outs or glands, which allow  the 
connection of the appropriate types of cable or conduit  
shall allow the connection of the supply conductors after the appliance has been fixed to its 
support.  
If a fixed appliance is constructed so that parts can be removed to facilitate easy installation, 
this requirement is considered to be met if it is possible to connect the fixed wiring without 
difficulty after a part of the appliance has been fixed to its support. In this case, removable parts 
are to be constructed for ease of reassembly without risk of incorrect assembly or damage to the wiring or terminals.  
Compliance is checked by inspection and, if necessary, by making the appropriate connections.  
25.4  For appliances intended to be permanently connected to the fixed wiring and having a 
rated current  not exceeding 16  A, cable and conduit entries shall be suitable for cables or 
conduits having a maximum overall dimension shown in Table  10. 
Table 10 – Dimensions of cables and conduits  
Number of conductors 
including earthing 
conductors Maximum overall dimension  
mm 
Cable  Conduit a 
2 13,0  16,0 (23,0)  
3 14,0  16,0 (23,0)  
4 14,5  20,0 (23,0)  
5 15,5  20,0 (29,0)  
a The dimensions in parentheses are for use in USA and Canada.  
 
Conduit entries, cable entries and knock -outs shall be constructed or located so that the 
introduction of the conduit or cable does not reduce clearances or creepage distances  below 
the values specified in Clause 29. 
Compliance is checked by inspection and by measurement.  
25.5  Supply cords  shall be assembled to the appliance by one of the following methods:  
– type X attachment ; 
– type Y attachment ; 
– type Z attachment , if allowed in the relevant part 2.  
Type X attachments , other than those having a specially prepared cord, shall not be used for 
flat twin tinsel cords.  
For multi -phase appliances that are supplied with a supply cord and that are intended to be 
permanent ly connected to the fixed wiring, the  supply cord shall be assembled to the appliance 
by a type Y attachment.  IEC 60335- 1:2020 © IEC 2020 – 95 –          Compliance is checked by inspection.  
25.6  Plugs shall not be fitted with more than one flexible cord.  
Compliance is checked by inspection.  
25.7  Supply cords  for appliances other than class III appliances  shall be one of the following 
types:  
– Rubber sheathed 
Their properties shall be at least those of ordinary tough rubber sheathed cords (code 
designation 60245 IEC 53).  
These supply cords  shall not be used on appliances intended to be used outdoors or when 
they are liable to be exposed to significant amounts of ultraviolet radiation.  
– Polychloroprene sheathed  
Their properties shall be at least those of ordinary polychloroprene sheathed cords (code designation 60245 IEC 57).  
These supply cords may be connected to appliances intended to be used in low 
temperature applications.  
– Polyvinyl chloride sheathed  
These supply cords  shall not be used if they are likely to touch metal parts having a 
temperature rise exceeding 75  K during the test of Clause  11. Their properties shall be at 
least those of : 
• light polyvinyl chloride sheathed cord (code designation 60227 IEC 52), for appliances having a mass not exceeding 3 kg; 
• ordinary polyvinyl chloride sheathed cord (code designation 60227 IEC 53), for other appliances.  
– Heat resistant polyvinyl chl oride sheathed 
These supply cords shall not be used for type X attachment  other than specially prepared 
cords.  Their properties shall be at least those of: 
• heat -resistant light polyvinyl chloride sheathed cord (code designation 60227  IEC 56), 
for appliances having a mass not exceeding 3  kg; 
• heat -resistant polyvinyl chloride sheathed cord (code designation 60227 IEC 57), for 
other appliances.  
– Halogen -free, low smoke, thermoplastic insulated and sheathed 
Their properties should at least be those of : 
• light duty halogen- free low smoke flexible cable (code designation 62821 IEC 101 for 
circular cable and code designation 62821 IEC 101f for flat cable);  
• ordinary duty halogen- free, low smoke flexible cable (code designation 62821 IEC 102 
for circular cable and c ode designation 62821 IEC 102f for flat cable).  
Supply cords  for class III appliances shall be adequately insulated.  
Compliance is checked by inspection, by measurement, and for class III appliances that 
contain live parts, by the following test.  
A voltage of 500 V is applied for 2  min between the conductor and metal foil wrapped around 
the insulation, the insulation being at the temperature measured during the test of Clause  11. 
There shall be no breakdown during this test.  
25.8  Conductors of supply cords  shall have a nominal cross -sectional area not less than that 
shown in Table 11.  – 96 – IEC 60335- 1:2020 ©  IEC 20 20        Table 11 – Minimum cross- sectional area of conductors  
Rated current of appliance  Nominal cross -sectional area 
A mm2 
  ≤0,2 Tinsel cord a 
>0,2  and ≤2,5 0,5 a 
>2,5  and ≤6 0,75  
>6 and ≤10 1,0 (0,75)b 
>10 and ≤16 1,5 (1,0)b 
>16 and ≤25 2,5 
>25 and ≤32 4 
>32 and ≤40 6 
>40 and ≤63 10 
NOTE  For supply cords supplied with multi -phase appliances, the nominal cross -
sectional area of the conductors is based on the maximum cross -sectional area of the 
conductors per phase at the supply cord connection to the appliance terminals.  
a These cords may only be used if their nominal length does not exceed 2 m 
between the point where the cord enters the appliance and the entry to the plug.  
b Cords having the cross -sectional areas indicated in the parentheses may be used 
for portable appliances if their length does not exceed 2  m. 
 
Compliance is checked by measurement.  
25.9  Supply cords shall not be in contact with sharp points or edges of the appliance.  
Compliance is checked by inspection.  
25.10  The supply cord of class I appliances  shall have a green/yellow core that is connected 
to the earthing terminal of the appliance and for appliances not intended for permanent 
connection to the fixed wiring, to the earthing contact of the plug.  
In multi -phase appliances, the colour of the neutral conductor of the supply cord , if any, shall 
be blue.  
Where additional neutral conductors are provided in the supply cord : 
– other colours may be used for these additional neutral conductors;  
– all of the neutral conductors and line conductors shall be identified by marking using the 
alphanumeric notation specified in IEC 60445;  
– the supply cord shall be fitted to the appliance.  
Compliance is checked by inspection.  
25.11  Conductors  of supply cords shall not be consolidated by soldering where they are 
subjected to contact pressure, unless the contact pressure is provided by spring terminals.  
The requirement does not apply to the soldered tip of a stranded conductor.  
Compliance is checked by inspection.  
25.12  The insulation of the supply cords  shall not be damaged when moulding the cord to part 
of the enclosure.  IEC 60335- 1:2020 © IEC 2020 – 97 –          Compliance is checked by inspection.  
25.13  Inlet openings for supply cords  shall be constructed so that the sheath of the supply 
cord can be introduced without risk of damage.  If it is not evident from the construction of the 
appliance that the supply cord can be introduced without risk of damage, a non -detachable 
lining  or non-detachable bushing shall be provided that complies with 29.3  for 
supplementary insulation . If the supply cord is unsheathed, a similar additional bushing or 
lining is required, unless the appliance is a class 0 appliance or a class III appliance  that 
does not contain live parts . 
Compliance is checked by inspection.  
25.14  Appliances provided with a supply cord  and that are moved while in operation shall be 
constructed so that the supply cord is adequately protected against excessive flexing where it 
enters the appliance.  
This requirement does not apply to appliances with automatic cord reels that comply with the 
requirement and test of 22.16 . 
Compliance is checked by the following test that is carried out on an apparatus having an oscillating member as shown in Figure 8. 
The part of the appliance that includes the inlet opening is fixed to the oscillating member so that, when the supply cord is at the middle of its travel, the axis of the cord where it enters the 
cord guard or inlet is vertical and passes through the axis of oscillation. The major axis of the 
section of flat cords shall be parallel to the axis of oscillation.  
The cord is loaded so that the force applied is : 
– 10 N, for cords having a nominal cross -sectional area exceeding 0,75  mm
2; 
– 5 N, for other cords.  
The distance X, as shown in Figure 8, between the axis of oscillation and the point where the 
cord or cord guard enters the appliance, is adjusted so that when the oscillating member moves over its full range, the cord and load make the minimum lateral movement.  
The oscillating member is moved through an angle of 90° (45° on either side of the vertical), 
the number of flexings for type Z attachments  being 20 000 and for other attachments 10 000. 
A flexing is one movement of 90°. The rate of flexing is 60 per minute.  
The cord and its associated parts are turned through an angle of 90° after half the number of 
flexings, unless a flat cord is fitted.  
During the test, the conductors are supplied at rated voltage and loaded with the rated current  
of the appliance. Current is not passed through the earthing conductor  or functional earthing 
conductor . 
The test shall not result in : 
– a short circuit between the  conductors,  such that the current exceeds a value equal to twice 
the rated current  of the appliance;  
– a breakage of more than 10 % of the strands of any conductor;  
– separation of the conductor from its terminal;  
– loosening of any cord guard;  
– damage to the cord or cord guard which could impair compliance with this standard;  
– broken strands piercing the insulation and becoming accessible.   – 98 – IEC 60335- 1:2020 ©  IEC 20 20        25.15  Appliances provided with a supply cord, and appliances intended to be permanently 
connected to fixed wiring by a flexible cord, shall have a cord anchorage. The cord anchorage 
shall relieve conductors from strain, including twisting, at the terminals and protect the insulation of the conductors from abrasion.  
It shall not be possible to push the cord into the appliance to such an extent that the cord or internal parts of the appliance could be damaged.  
Compliance is checked by inspection, by manual test and by the following test.  
A mark is made on the cord at a distance of approximately 20  mm from the cord anchorage or 
other suitable point.  The mark is made while the cord is subjected to a pull force of : 
– 100 N, for fixed appliances regardless of the mass of the appliance;  
– the value as shown in Table 12, for other appliances.  
The cord is then pulled, without jerking, for 1  s in the most unfavourable direction with the force 
specified. The test is carried out 25 times.  
The cord, unless on an automatic cord reel, is then subjected to a torque that is applied as close as possible to the appliance. The torque is specified in Table 12 and is applied for 1 min. 
Table 12 – Pull force and torque  
Mass of appliance Pull force  Torque 
kg N Nm 
≤ 1 30 0,10  
>1 and ≤ 4 60 0,25  
> 4 100 0,35  
 
During the tests, the cord shall not be damaged and shall show no appreciable strain at the 
terminals. The pull force is reapplied and the cord shall not be longitudinally displaced by more 
than 2 mm.  
25.16  Cord anchorages for type X attachments  shall be constructed and l ocated so that : 
– replacement of the cord is easily possible;  
– it is clear how the relief from strain and the prevention of twisting are obtained;  
– they are suitable for the different types of supply cord that may be connected, unless the 
cord is specially pre pared;  
– the cord cannot touch the clamping screws of the cord anchorage if these screws are accessible, unless they are separated from accessible metal parts  by supplementary 
insulation; 
– the cord is not clamped by a metal screw which bears directly on the cord;  
– at least one part of the cord anchorage is securely fixed to the appliance, unless it is part 
of a specially prepared cord. However, this does not apply if : 
• the cord anchorage comprises one or more clamping members to which pressure is applied by means of nuts engaging with studs that are securely attached to the appliance, 
even if the clamping member can be removed from the studs;  
• one of the clamping members is fixed to the appliance or the surface of the appliance is of insulating material and shaped so that it is obvious that this surface is one of the clamping members; IEC 60335- 1:2020 © IEC 2020 – 99 –          NOTE  1 If the pressure on the clamping members is applied by means of one or more screws engaging with separate 
nuts or with a thread in a part that is integral with the appliance, the cord anchorage is not considered to have one 
part securely fixed to the appliance.  
– screws which have to be operated when replacing the cord do not fix any other component. 
However, this does not apply if : 
• after removal of the screws, or if the component is incorrectly repositioned, the appliance becomes inoperative or is obviously incomplete;  
• the parts intended to be fastened by them cannot be removed without the aid of a tool 
during the replacement of the cord;  
– if labyrinths can be bypassed, the test of 25.15 is nevertheless withstood;  
– for class 0 appliances,  class 0I appliances and class I appliances, they are of insulatin g 
material or are provided with an insulating lining, unless failure of the insulation of the cord does not make accessible metal parts live; 
– for class II appliances, they are of insulating material or, if of metal, they are insulated from 
accessible metal  parts  by supplementary insulation . 
NOTE  2 Examples of acceptable and unacceptable constructions of cord anchorages are shown in Figure 9. 
Compliance is checked by insp ection and by the test of 25.15  under the following conditions.  
The tests are carried out with the lightest permissible type of cord of the smallest cross -sectional 
area specified in Table 13 and then with the next heavier t ype cord having the largest cross -
sectional area specified. However, if the appliance is fitted with a specially prepared cord, the 
test is carried out with this cord.  
The conductors are placed in the terminals and any terminal screws tightened just suffic iently 
to prevent the conductors from easily changing their position. The clamping screws of the cord anchorage are tightened with two- thirds of the torque specified in 28.1 . 
Screws of insulating material bearing directly on the cord are fastened with two -thirds of the 
torque specified in column I of Table 14, the length of the slot in the screw head being taken as 
the nominal diameter of the screw.  
After the test, the conductors shall not have moved by more than 1 mm in the terminals.  
25.17  For type Y attachment  and type Z attachment , cord anchorages shall be adequate.  
Compliance is checked by the test of 25.15 with the cord supplied with the appliance.  
25.18  Cord anchorages shall be arranged so that they are only accessible with the aid of a tool 
or shall be constructed so that the cord can only be fitted with the aid of a tool. 
Compliance is checked by inspection.  
25.19  For type X attachment , glands shall not be used as cord anchorages in portable 
appliances . Tying the cord into a knot or tyi ng the cord with string is not allowed.  
Compliance is checked by inspection.  
25.20  The conductors of the supply cord for type Y attachment  and type Z attachment  shall 
be insulated from accessible metal parts by basic insulation  for class 0 appliances , class 
0I a ppliances and class I appliances,  and by supplementary insulation for class II 
appliances . This insulation may be provided by the sheath of the supply cord or by other 
means.  
Compliance is checked by inspection and by the relevant tests.   – 100 – IEC 60335- 1:2020 ©  IEC 20 20        25.21  The space for the connection of supply cords having type X attachment , or for the 
connection of fixed wiring, shall be constructed: 
– so that it is possible to check that the supply conductors are correctly positioned and 
connected before fitting any cover;  
– so that any cover can be fitted without risk of damage to the conductors or their insulation;  
– for portable appliances, so that the uninsulated end of a conductor, should it become free 
from the terminal, cannot come into contact with accessible metal parts . 
Compliance is checked by inspection after fitting cables or flexible cords having the largest 
cross- sectional area specified in Table 13. 
Portable appl iances  are subjected to the following additional test unless they are provided 
with pillar terminals and the supply cord is clamped within 30 mm of them. The cord anchorage 
may be used to provide the clamping.  
The clamping screws or nuts are loosened in turn. A force of 2 N is applied to the conductor in 
any direction at a position adjacent to the terminal. The uninsulated end of the conductor shall not come into contact with accessible metal parts . 
25.22  Appliance in lets shall: 
– be located or enclosed so that live parts  are not accessible during insertion or removal of 
the connector. This requirement is not applicable to appliance inlets complying with 
IEC 60320 -1; 
– be located so that the connector can be inserted without difficulty;  
– be located so that, after insertion of  the connector, the appliance is not supported by the 
connector when it is placed in any position of normal use on a flat surface;  
– not be an appliance inlet for cold conditions if the temperature rise of external metal parts 
of the appliance exceeds 75  K during the test of Clause  11, unless the flexible cord of the 
cord set is unlikely to touch such metal parts in normal use.  
Compliance is checked by inspection.  
25.23  Interc onnection cords  shall comply with the requirements for the supply cord, except 
that: 
– the cross- sectional area of the conductors of the interconnection cord is determined on 
the basis of the maximum current carried by the conductor during the test of Clause  10 and 
not by the rated current  of the appliance. If the measured current in the interconnection 
cord  is greater than the rated current  but does not exceed the rated current  by more than 
the current deviation in Table 2, the cross- sectional area of the conductors in the 
interconnection cord do not need to be greater than the cross -sectional area of the 
conductors in the supply cord; 
– the thickness of the insulation of the conductor may be reduced if the voltage of the conductor is less than the rated voltage ; 
– for class III construction , interconnection co rds of a class I appliance or class II 
appliance , the cross- sectional areas of the conductors need not  comply with 25.8 if the 
temperature of the cord insulation specified in Table 3 and Table 9 are not exceeded during 
the tests of Clause  11 and Clause  19, respectively.  
Com pliance is checked by inspection, by measurement and , if necessary , by tests, such as the 
electric strength test of 16.3. 
25.24  Interconnection cords  shall not be detachable without the aid of a tool if compliance 
with this standard is impaired when they are disconnected.  
Compliance is checked by inspection and if necessary by appropriate tests.  IEC 60335- 1:2020 © IEC 2020 – 101 –         25.25  The dimensions of pins of appliances that are inserted into socket -outlets shall be 
compatible with the dimensions of the relevant socket -outlet. Dimensions of the pins and 
engagement face are to be in accordance with the dimensions of the relevant plug listed in  
IEC TR 60083.  
Compliance is checked by measureme nt. 
26 Terminals for external conductors  
26.1  Appliances shall be provided with terminals or equally effective devices, such as male 
tabs of  flat quick -connect terminations in accordance with IEC 61210, s crew type terminals in 
accordance with IEC 60998-2- 1, screwl ess terminals in accordance with IEC 60998 -2-2 and 
clamping units in accordance with IEC 60999-1 :1999 , for the connection of external conductors. 
The terminals of a component such as a switch may also be used as terminals for external 
conductors as long as  they comply with the requirements of this clause.  
The terminals, other than terminals in class III appliances  that do not contain live parts , shall 
only be accessible after the removal of a non-detachable cover . However, earthing terminals 
and functional earthing terminals may be accessible if a tool  is required to make the 
connections and means are provided to clamp the wire independently from its connection.  
Compliance is checked by inspection and by manual test.  
26.2  Appliances having type X attachment , except those having a specially prepared cord, 
and appliances for the connection  of cables of fixed wiring shall be provided with terminals in 
which the connections are made by means of screws, nuts or similar devices, unless the connections are soldered.  
The screws and nuts shall not be used to fix any other component except that they may also 
clamp internal conductors if these are arranged so that they are unlikely to be displaced when 
fitting the supply conductors . 
If soldered connections are used, the conductor shall be positioned or fixed so that reliance is 
not placed upon the soldering alone to maintain it in position. However, soldering alone may be used if barriers are provided so that neither clearances  nor creepage distances between live 
parts  and other metal parts can be reduced below the values specified for supplementary 
insulation if the conductor becomes free at the soldered joint.  
Compliance is checked by inspection and by measurement.  
26.3  Terminals for type X attachment  and those for the connection of cables of fixed wiring 
shall be constructed so that they clamp the conductor between metal surfaces with sufficient 
contact pressure but without causing damage to the conductor.  
The terminals shall be fixed s o that when the clamping means is tightened or loosened : 
– the terminal does not become loose.  This does not apply if the terminals are fixed with two 
screws, or are fixed with one screw in a recess so that there is no appreciable movement 
or if they are not  subject to torsion in normal use and they are locked by a self -hardening 
resin;  
– internal wiring is not subjected to stress;  
– neither clearances  nor creepage distances are reduced below the values specified 
in Clause  29.  
Compliance is checked by inspection and by the test of Subclause 9.6  of IEC 60999 -1:1999 , 
the torque applied being equal to two- thirds of the torque specified.   – 102 – IEC 60335- 1:2020 ©  IEC 20 20        After the test, the conductors shall show no deep or sharp indentations.  
26.4  Terminals for type X attachment, except type X attachments having a specially 
prepared cord, and terminals for the connection of cables of fixed wiring, shall not require 
special preparation of the conductor such as by s oldering of the strands of the conductor, the 
use of cable lugs, eyelets or similar devices.  Reshaping of the conductor before its introduction 
into the terminal or twisting a stranded conductor to consolidat e the end is not considered 
special preparation.  
The termi nals shall be constructed or placed so that the conductor cannot slip out when 
clamping screws or nuts are tightened.  
Compliance is checked by inspection of the terminals and conductors after the test of 26.3 . 
26.5  Terminals for type X attachment  shall be located or shielded so that if a wire of a 
stranded conductor escapes when the conductors are fitted, there is n o risk of accidental 
connection to other parts that could result in a hazard.  
Compliance is checked by inspection and by the following test. 
A 8 mm length of insulation is removed from the end of a flexible conductor having a nominal 
cross- sectional area as specified in Table 11. One wire of t he stranded conductor is left free 
and the other wires are fully inserted and clamped in the terminal. The free wire is bent, without 
tearing the insulation back, in every possible direction but without making sharp bends around barriers.  
There shall be no contact between live parts and accessible metal parts and, for class II 
constructions , between live parts and metal parts separated from accessible metal parts by 
supplementary insulation  only.  
26.6  Terminals for type X attachment  and for the connection  of cab les of fixed wiring shall 
allow the connection of conductors having the nominal cross -sectional areas shown in Table  13. 
However, if a specially prepared cord is used, the terminals need only be suitable for the connection of that cord.  
Table 13 – Nominal cross- sectional area of conductors  
Rated current of appliance  Nominal cross -sectional area 
A mm2 
 Flexible cords  Cable for fixed wiring  
  ≤ 3  0,5 and  0,75   1 to 2,5 
 > 3 and  ≤ 6  0,75  and 1  1 to 2,5 
 > 6 and  ≤ 10   1 and  1,5  1 to 2,5 
 > 10 and  ≤ 16   1,5 and  2,5  1,5 to 4 
 > 16 and  ≤ 25   2,5 and  4  2,5 to 6 
 > 25 and  ≤ 32   4 and  6  4 to 10 
 > 32 and  ≤ 50   6 and  10  6 to 16 
 > 50 and  ≤ 63   10 and  16  10 to 25 
 
Compliance is checked by inspection, by measurement and by fitting cables or cords of the smallest and largest cross -sectional areas specified.  IEC 60335- 1:2020 © IEC 2020 – 103 –         26.7  Terminals for type X attachment , other than those in class III appliances that do not 
contain live parts, shall be accessible after removal of a cover or part of the enclosure.  
Compliance is checked by inspection.  
26.8  Terminals for the connection of fixed wiring, including the earthing terminal, shall be 
located close to each other.  
Compliance is checked by inspection.  
26.9  Terminals of the pillar type shall be constructed and located so that the end of a 
conductor introduced into the hole is visible, or can pass beyond the threaded hole for a 
distance equal to half the nominal diameter of the screw but at least 2,5 mm. 
Compliance is checked by inspection and by measurement.  
26.10  Terminals with screw clamping and screwless terminals shall not be used for the 
connection of the conductors of flat twin tinsel cords unless the ends of the conductors are fitted with means suitable for use with screw terminals.  
Compliance is checked by inspection and by applying a pull of 5  N to the connection.  
After the test, the connection shall show no damage that could impair compliance with this standard.  
26.11  For appliances having type Y attachment  or type Z attachment , soldered, welded, 
crimped or similar connections may be used for the connection of external conductors. For 
class II appliances , the conductor shall be positioned or fixed so that reliance is not placed 
upon the soldering, crimping or welding alone to maintain the conductor in position. However, 
these methods may be used alone if barriers are provided so that clearances and creepage 
distances  between live parts  and other metal parts cannot be reduced below the values 
specified for supplementary insulation , if the conductor becomes free at the soldered or 
welded joint or slips out of the crimped connection.  
Compliance is checked by inspection and by measurement.  
27 Provision for earthing 
27.1  Accessible metal parts, including  metal parts behind a decorative cover t hat does not 
withstand the test of 21.1, of class 0I appliances and class I appliances  that may become 
live in the event of  a failure of basic insulation , shall be pe rmanently and reliably connected 
to an earthing terminal within the appliance or to the earthing contact of the appliance inlet.  
Earthing terminals and earthing contacts shall not be connected to the neutral terminal.  
Class 0 appliances,  class II appliances and class III appliances shall have no provision for 
protective earthing . 
Safety extra -low voltage  circuits shall not be earthed unless they are protective extra- low 
voltage circuits. 
Compliance is checked by inspection.  
27.2  The clamping m eans of earthing terminals shall be adequately secured against 
accidental loosening.   – 104 – IEC 60335- 1:2020 ©  IEC 20 20        Terminals for the connection of external equipotential bonding conductors shall allow the 
connection of conductors having nominal cross- sectional areas of 2,5 mm2 to 6 mm2 and shall 
not be used to provide earthing continuity between different parts of the appliance. It shall not 
be possible to loosen the conductors without the aid of a tool. 
NOTE  The terminal for the earthing conductor in a supply cord is not a terminal for  external equipotential bonding 
conductor s. 
Compliance is checked by inspection and by manual test.  
27.3  If a detachable part having an earth connection is plugged into another part of the 
appliance, the earth connection shall be made before the current -carryin g connections are 
established. The current -carrying connections shall be separated before the earth connection 
when removing the part.  
For appliances with supply cords , the arrangement of the terminals, or the length of the 
conductors between the cord anchorage and the terminals, shall be such that the current -
carrying conductors become taut before the earthing conductor if the cord slips out of the cord anchorage.  
Compliance is checked by inspection and by manual test.  
27.4  All parts of the earthing terminal intended for the connection of external conductors shall 
be such that there is no risk of corrosion resulting from contact between these parts and the copper of the earthing conductor or any other metal in contact with these parts.  
Parts providing earthing c ontinuity, other than parts of a metal frame or enclosure, shall be of 
metal having adequate resistance to corrosion, unless they are parts of copper or copper alloys 
containing at least 58 % copper for parts that are processed by cold forming, and at least 50  % 
copper for other parts, or unless they are parts of stainless steel containing at least 13  % 
chrome. If these parts are of steel, they shall be provided with an electroplated coating having 
a thickness of at least 5  µm at essential areas such as those liable to transmit a fault current.  
Parts of coated or uncoated steel that are only intended to provide or to transmit contact 
pressure shall be adequately protected against rusting.  
NOTE  1 Examples of parts providing earthing continuity and parts that are only intended to provide or to transmit 
contact pressure are shown in Figure 10. 
NOTE 2 Parts subjected to a treatment such as chromate conversion coating are in general not considered to be 
adequately protected against corrosion, but they can be used to provide or to transmit contact pressure.  
If the body of the earthing terminal is a part of a frame or enclosure of aluminium or aluminium alloy, precautions shall be taken to avoid the risk of corrosion resulting from contact between copper and aluminium or its alloys.  
Compliance is checked by inspection and by measurement.  
In case of doubt, the thickness of the coating is measured as described in ISO  2178 or in 
ISO 1463.  
27.5  The connection between the earthing terminal or earthing contact and earthed metal 
parts shall have low resistance.  
If the clearances  of basic insulation  in a protective extra- low voltage circuit are based on 
the rated voltage of the appliance, this  requirement does not apply to connections providing 
earthing continuity in the protective extra- low voltage circuit . 
Compliance is checked by the following test.  IEC 60335- 1:2020 © IEC 2020 – 105 –         A current derived from a source having a no -load voltage not exceeding 12  V (AC or DC) and 
equal to 1,5  times rated current  of the appliance or 25  A, whichever is higher, is passed 
between the earthing terminal or earthing contact and each of the accessible metal parts  in 
turn. The test is carried out until steady conditions have been established.  
The voltage drop between the earthing terminal of the appliance or the earthing contact of the 
appliance inlet and the accessible metal part is measured. The resistance calculated from the 
current and this voltage drop shall not exceed 0,1 Ω. The resistance of the supply cord is not 
included in the resistance calculation.  
27.6  The printed conductors of printed circuit boards shall not be used to provide earthing 
continuity in hand- held appliances . They may be used to provide earthing continuity in other 
appli ances if at least two tracks are used with independent soldering points and the appliance 
complies with 27.5  for each circuit.  
Compliance is checked by inspection and by the relevant tests.  
28 Screws and connections  
28.1  Fixings , the failure of which may impair compliance with this standard, electrical 
connections and connections providing earthing continuity shall withstand the mechanical stresses occurring in normal use.  
Screws used for these purposes shall not be of metal that is soft or liable to creep, such as zinc 
or aluminium. If they are of insulating material, they shall have a nominal diameter of at least 3 mm and they shall not be used for any electrical connections or connections providing 
earthing continuity.  
Screws used for electrical connections or for connections providing earthing continuity shall 
screw into metal.  
Screws shall not be of insulating material if their replacement by a metal screw could impair 
supplementary insulation or reinforced insulation . Screws that may be removed when 
replacing a supply cord  having a type X attachment or when undertaking user maintenance 
shall not be of insulating material if their replacement by a metal screw could impair basic 
insulation. 
Compliance is checked by inspection and by the following test. Screws and nuts are tested if they are : 
– used for electrical connections;  
– used for connections providing earthing continuity, unless at least two screws or nuts are 
used; 
– likely to be tightened: 
• during user maintenance ; 
• when replacing a supply cord having a type X attachment ; 
• during installation.  
The screws or nuts are tightened and loosened without jerking:  
– 10 times for screws in engagement with a thread of insulating material;  
– 5 times for nuts and other screws.  
Screws in engagement with a thread of insulating material are completely removed and 
reinserted each time.   – 106 – IEC 60335- 1:2020 ©  IEC 20 20        When testing terminal screws and nuts, a cable or flexible cord of the largest cross -sectional 
area specified in Table 13 is placed in the terminal. It is repositioned before each tightening.  
The test is carried out by means of a suitable screwdriver, spanner or key and by applying a 
torque as shown in Table 14. 
Column I is applicable for metal screws without heads if the screw does not protrude from the hole when tightened.  
Column II is applicable  for: 
– other met al screws and for nuts;  
– screws of insulating material : 
• having a hexagonal head with the dimension across flats exceeding the overall thread 
diameter;  
• with a cylindrical head and a socket for a key, the socket having a cross -corner 
dimension exceeding the o verall thread diameter;  
• with a head having a slot or cross -slots, the length of which exceeds 1,5 times the 
overall thread diameter.  
Column III is applicable for other screws of insulating material.  
Table 14 – Torque for testing screws and nuts  
Nominal diameter of screw  
(outer thread diameter)  Torque 
mm Nm 
 I II III 
   ≤ 2,8 0,2 0,4 0,4 
 > 2,8  and  ≤ 3,0  0,25  0,5 0,5 
 > 3,0  and  ≤ 3,2  0,3 0,6 0,5 
 > 3,2  and  ≤ 3,6  0,4 0,8 0,6 
 > 3,6  and  ≤ 4,1  0,7 1,2 0,6 
 > 4,1  and  ≤ 4,7  0,8 1,8 0,9 
 > 4,7  and  ≤ 5,3  0,8 2,0 1,0 
 > 5,3 – 2,5 1,25  
 
No damage impairing the further use of the fixings or connections shall occur.  
28.2  Electrical connections and connections providing earthing continuity shall be constructed 
so that contact pressure is not transmitted through non -ceramic insulating material that is liable 
to shrink or to distort unless there is sufficient resiliency in the metallic parts to compensate for 
any possible shrinkage or distortion of the  insulating material.  
This requirement does not apply to electrical connections in circuits of appliances for which : 
– 30.2.2 is applicable and that carry a current not exceeding 0,5 A; 
– 30.2.3 is applicable and that carry a cur rent not exceeding 0,2 A. 
Compliance is checked by inspection.  
28.3  Space- threaded (sheet metal) screws shall only be used for electrical connections if they 
clamp the parts together.  IEC 60335- 1:2020 © IEC 2020 – 107 –         Thread- cutting (self -tapping) screws and thread rolling screws shall only be used for electrical 
connections if they generate a full form standard machine screw thread. However, thread-
cutting (self -tapping) screws shall not be used if they are likely to be operated by the user or 
installer.  
Thread- cutting, thread rolling and space -threaded screws may be used in connections providing 
earthing continuity provided it is not necessary to disturb the connection: 
– in normal use ; 
– during user maintenance ; 
– when replacing a supply cord having a type X attachment ; or  
– during installation. 
At least two screws shall be used for each connection providing earthing continuity, unless the 
screw forms a thread having a length of at least half the diameter of the screw.  
Compliance is checked by inspection.  
28.4  Screws and nuts that make a mechanical connection between different parts of the 
appliance shall be secured against loosening by means such as spring washers, lock washers 
and crown type locks as part of the screw head,  if they also make electrical connections or 
connections providing earthing continuity. Sealing compound that softens on heating may also 
be used to provide security against loosening but only for screw connections not subject to 
torsion in normal use.  
This requirement does not apply to screws in the earthing circuit if at least two screws are used for the connection or if an alternative earthing circuit is provided.  
Rivets used for electrical connections or for connections providing earthing continuity shall be 
secured against loosening if these connections are subject to torsion in normal use. A rivet 
having a non- circular shank or an appropriate notch may be used to secure against loosening 
if these connections are subject to torsion in normal use.  
NOTE  This requirement does not imply that more than one rivet is  necessary for providing earthing continuity.  
Compliance is checked by inspection and by manual test.  
29 Clearances, creepage distances and solid insulation  
Appliances shall be constructed so that the clearances , creepage distances  and solid 
insulation are adequate to withstand the electrical stresses to which the appliance is liable to be subjected.  
Compliance is checked by the requirements and tests of 29.1 to 29.3  that are carried out 
separately.  
If coatings are used on printed circuit boards to protect the microenvironment (type 1 protection) or to provide basic insulation  (type 2 protection), normative  Annex  J applies. The 
microenvironment is pollution degree 1 under type 1 protection. For type 2 protection, the 
spacing between the conductors before the protection is applied shall not be less than t he 
values as specified in Table 1 of IEC 60664 -3:2016 . These values apply to functional 
insulation, basic insulation , supplementary insulation  as well as reinforced insulation . 
NOTE  The requirements and tests are based on IEC  60664 -1:2007  from which further information can be obtained.   – 108 – IEC 60335- 1:2020 ©  IEC 20 20        29.1  Clearances shall not be less than the values specified in Table 16, taking into account 
the rated impulse voltage for the overvoltage categories of Table 15, unless, for basic 
insulation and functional insulation , they comply with the impulse voltage test of Clause  14. 
For appliances intended for use at altitudes exceeding 2 000 m, the clearances  in Table 16 
shall be increased according to the altitude correction factor  in Table A.2 of IEC 60664 -1:2007.  
If the construction is such that the distances could be affected by any of the following: 
– distortion; 
– movement of parts ; 
– assembly  of parts ; 
– wear of basic insulation ;  
– wear of functional insulation , 
the impulse voltage test is not applicable and the clearances for rated impulse voltages of 
1 500 V and above specified in Table 16 are increased by 0,5  mm. 
The impulse voltage test is not applicable : 
– when the microenvironment is pollution degree 3; or 
– for basic insulation  of class 0 appliances and class 0I appliances ; or 
– to appliances intended for use at altitudes exceeding 2  000 m. 
Appliances are in overvoltage category II.  
NOTE  1 Informative  Annex  K gives information regarding overvoltage categories.  
Table 15 – Rated impulse voltage 
Rated voltagea Rated impulse voltage  
V V 
 Overvoltage category  
 I II III 
≤ 50 330  500 800 
> 50 and ≤ 150 800 1 500  2 500  
> 150 and ≤ 300 1 500  2 500  4 000  
NOTE  The values are based on the assumption that the appliance will not generate higher overvoltages than 
those specified. If higher overvoltages are generated, the clearances  have to be increased accordingly.  
a For multi -phase appliances, the line to neutral or line to earth voltage is used for rated voltage. 
 IEC 60335- 1:2020 © IEC 2020 – 109 –         Table 16 – Minimum clearances 
Rated impulse voltage  Minimum clearance a 
V mm 
330  0,5 b, c, d  
 500  0,5 b, c, d 
 800  0,5 b, c, d 
1 500   0,5 c 
2 500   1,5 
4 000   3,0 
6 000   5,5 
8 000   8,0 
10 000   11,0  
NOTE  If the rated impulse voltage is not specified in the table, clearances for 
intermediate values of Table 16 can be determined by interpolation.  
a The distances specified apply only to clearances in air. 
b The smaller clearances specified in IEC 60664-1 :2007 have not been adopted for 
practical reasons, such as mass- production tolerances.  
c This value is increased to 0,8 mm for pollution degree 3.  
d For tracks of printed circuit boards , this value is reduced to 0,2  mm for pollution 
degree 1 and pollution degree 2.  
 
Compliance is checked by inspection and by measurement.  
Parts, such as hexagonal nuts that can be tightened to different positions during assembly, and 
movable parts are placed in the most unfavourable position.  
A force is applied to bare conductors, other than those of heating elements, and accessible surfaces  to try to reduce clearances when making the measurement. The force is : 
– 2 N, for bare conductors;  
– 30 N, for accessible surfaces. 
The force is applied by means of test probe B of IEC  61032. Apertures are assumed to be 
covered by a piece of flat metal.  
NOTE  2 The way in which clearances  are measured is specified in IEC  60664-1 :2007. 
NOTE  3 The procedure for assessing clearances is giv en in informative Annex  L. 
29.1.1  The clearances  of basic insulation  shall be sufficient to withstand the overvoltages 
likely to occur during use, taking into account the rated impulse voltage . The values of 
Table  16, or the impulse voltage test of Clause  14, are applicable.  
The clearance  at the terminals of tubular sheathed heating elements may be reduced to 1,0 mm 
if the microenvironment is pollution degree 1.  
Lacquered conductors of windings are considered to be bare conductors.  
Compliance is checked by measurement.  
29.1.2  Clearances of supplementary insulation  shall be not less than those specified in 
Table 16.  – 110 – IEC 60335- 1:2020 ©  IEC 20 20        Compliance is checked by measurement.  
29.1.3  Clearances of reinforced insulation  shall be not less than those specified in  
Table 16, using the next higher step for rated impulse voltage  as a reference.  
Compliance is checked by measurement. For  double insulation, when there is no intermediate 
conductive part between the bas ic insulation  and supplementary insulation , clearances   
are measured between live parts  and the accessible surface , and the insulation system is 
treated as reinforced insulation as shown in Figure 11.  
29.1.4  The clearances for functional insulation  are the largest values determined from : 
– Table 16 based on the rated impulse voltage ; 
– Table F.7a in IEC 60664-1 :2007  based on the steady -state voltage or recurring peak voltage 
expected to occur across it, if the frequency of the steady -state  voltage or recurring peak 
voltage does not exceed 30 kHz;  
– Clause 4 of IEC 60664 -4:2005  based on the steady -state voltage or recurring peak voltage 
expected to occur across it, if the frequency of the steady -state voltage or recurring peak 
voltage exceeds 30 kHz.  
If the values of Table 16 are largest, the impulse voltage test of Clause  14 may be applied 
instead unless the microenvironment is pollution degree 3 or the construction is such that the 
distances could be affected by wear, by distortion, by movement of the parts or during assembly.  
However, clearances  are not specified if the appliance complies with Clause 19 with the 
functional insulation short -circuited.  
Lacquered conductors of windings are considered to be bare conductors. However, clearances 
at crossover points are not measured.  
The clearance between surfaces of PTC heating elements  may be reduced to 1 mm.  
Compliance is checked by measurement and by a test if necessary.  
29.1.5  For appliances having higher working voltages  than  rated voltage , for example on 
the secondary side of a step -up transformer, or if there is a resonant voltage, the clearances  
for basic insulation  are the largest values determined from : 
– Table 16 based on the rated impulse voltage ; 
– Table F.7a in IEC 60664-1 :2007  based on the steady -state voltage or recurring peak voltage 
expected to occur across it, if the frequency of the steady -state voltage or recurring peak 
voltage does not exceed 30 kHz;  
– Clause 4 of IEC 60664 -4:2005  based on the steady -state voltage or recurring peak voltage 
expected to occur across it, if the frequency of the steady -state voltage or recurring peak 
voltage exceeds 30  kHz.  
If the clearances applied for basic insula tion are selected from Table  F.7a of 
IEC 60664 -1:2007  or Clause 4 of IEC 60664-4 :2005 , then the clearances  of supplementary 
insulation shall be not less than those specified for basic insulation . 
If the clearances applied for basic insulation  are selected from Table  F.7a of 
IEC 60664 -1:2007 , then the clearances  of reinforced insulation  shall be dimensioned as 
specified in Table F.7a to withstand 160  % of the withstand voltage required for basic  
insulation. IEC 60335- 1:2020 © IEC 2020 – 111 –         If the clearances applied for basic i nsulation  are selected from Clause 4 of IEC 60664 -4:2005 , 
then the clearances  of reinforced insulation  shall be twice the value required for basic  
insulation. 
If the secondary winding of a step -down transformer is earthed, or if there is an earthed screen 
between the primary and secondary windings, clearances of basic insulation  on the 
secondary side shall be not less than those specified in Table 16, using the next lower step for 
rated impulse voltage as a reference.  
For circuits supplied with a voltage lower than rated voltage, for example on the secondary 
side of a transformer, clearances  of functional insulation  are based on the  working voltage , 
which is used as the rated voltage in Table 15. 
Compliance is checked by measurement.  
29.2  Appliances shall be constructed so that creepage distances  are not less than those 
appropriate for the working voltage, taking into account the material group and the pollution degree.  
NOTE  1 The working voltage for parts connected to the neutral is the same as for parts connected to the line and 
this is the working voltage for basic insulation. 
Pollution degree 2 applies unless : 
– precautions have been taken to protect the insulation, in which case pollution degree 1 
applies;  
– the insulation is subjected to conductive pollution, in which case pollution degree 3 applies.  
NOTE  2 An explanation of pollution degree is given in informative  Annex  M. 
Compliance is checked by measurement.  
NOTE  3 The way in which creepage distances are measured is specified in IEC  60664-1 :2007 . 
Parts such as hexagonal nuts that can be tightened to different positions during assembly, and 
movable parts are placed in the most unfavourable position.  
A force is applied to bare conductors, other than those of heating elements, and accessible 
surfaces  to try to reduce creepage distances  when making the measurement . The force is : 
– 2 N, for bare conductors;  
– 30 N, for  accessible surfaces. 
The force is applied by means of test probe B of IEC 61032.  
The relationship between the material group and the comparative tracking index (CTI) values, as given in Subclause 4.8.1.3  of IEC 60664-1 :2007 , is as follows:  
– material group I:  600 
≤ CTI; 
– material group II:  400 ≤ CTI < 600;  
– material group IIIa:  175 ≤ CTI < 400;  
– material group IIIb:  100 ≤ CTI < 175.  
These CTI values are obtained in accordance with IEC 60112:2003 including 
IEC 60112:2003/AMD1:2009 using solution A. If the CTI value of the material is unknown, a 
proof tracking index (PTI) test in accordance with normative  Annex  N is car ried out at the CTI 
values specified, in order to establish the material group.  
NOTE  4 The procedure for assessing creepage distances  is given in informative Annex  L.  – 112 – IEC 60335- 1:2020 ©  IEC 20 20        In a double insulation system, the working voltage for both the basic insulation and 
supplementary insulation is taken as the working voltage across the complete double 
insulation system. It is not divided according to thickness and dielectric constants of the basic 
insulation and supplementary insulation . 
29.2.1  Creepage distances of  basic insulation  shall not be less than those specified in 
Table 17. However, if the working voltage is periodic and has a frequency that exceeds 30  kHz, 
the creepage distances shall also be determined from Table 2 of IEC  60664 -4:2005. These 
values shall be used instead if they exceed the values in Table 17. 
Except for pollution degree 1, if the test of Clause  14 has been used to check a particular 
clearance , the corresponding creepage distance shall not be less than the minimum 
dimension specified for the clearance  of Table 16. 
 IEC 60335- 1:2020 © IEC 2020 – 113 –         Table 17 – Minimum creepage distances for basic insulation  
Working voltage Creepage distance 
V mm 
 Pollution degree 
1 2 3 
Material group  Material group  
I II IIIa/IIIb  I II IIIa/IIIb a 
  ≤ 50  0,18  0,6 0,85  1,2 1,5 1,7 1,9  
125   0,28  0,75  1,05  1,5 1,9 2,1 2,4 
250   0,56  1,25  1,8 2,5 3,2 3,6 4,0 
400   1,0 2,0 2,8 4,0 5,0 5,6 6,3 
500    1,3 2,5 3,6 5,0 6,3 7,1 8,0 
> 630 and ≤ 800  1,8 3,2 4,5 6,3 8,0 9,0 10,0  
> 800 and ≤ 1 000  2,4 4,0 5,6 8,0 10,0  11,0  12,5  
> 1 000  and ≤ 1 250  3,2 5,0 7,1 10,0  12,5  14,0  16,0  
> 1 250  and ≤ 1 600  4,2 6,3 9,0 12,5  16,0  18,0  20,0  
> 1 600 and ≤ 2 000  5,6 8,0 11,0  16,0  20,0  22,0  25,0  
> 2 000  and ≤ 2 500  7,5 10,0  14,0  20,0  25,0  28,0  32,0  
> 2 500  and ≤ 3 200  10,0  12,5  18,0  25,0  32,0  36,0  40,0  
> 3 200  and ≤ 4 000  12,5  16,0  22,0  32,0  40,0  45,0  50,0  
> 4 000  and ≤ 5 000  16,0  20,0  28,0  40,0  50,0  56,0  63,0  
> 5 000  and ≤ 6 300  20,0  25,0  36,0  50,0  63,0  71,0  80,0  
> 6 300  and ≤ 8 000  25,0  32,0  45,0  63,0  80,0  90,0  100,0  
> 8 000  and ≤ 10 000  32,0  40,0  56,0  80,0  100,0  110,0  125,0  
> 10 000  and ≤ 12 500  40,0  50,0  71,0  100,0  125,0  140,0  160,0  
NOTE  1 Lacquered conductors of windings are considered to be bare conductors, but creepage distances for 
basic insulation  in other than a double insulation construction need not be greater than the associated clearance  
specified in Table 16 taking into account 29.1.1. 
NOTE  2 For glass, ceramics and other inorganic insulating materials that do not track, creepage distances need 
not be greater than the associated clearance . 
NOTE  3 Except for circuits on the secondary side of an isolating transformer, the working voltage is considered 
to be not less than the rated voltage of the appliance.  
NOTE  4 For working voltages  > 50 V and ≤  630 V, if the voltage is not specified in the table, the values of 
creepage distances can be found by interpolation.  
a Material group IIIb is allowed if the working voltage  does not exceed 50  V. 
 
Compliance is checked by measurement.  
29.2.2  Creepage distances  of supplementary insulation shall be at least those specified 
for basic insulation  in Table 17 , excluding its NOTE 1 and NOTE 2, or Table 2 of  
IEC 60664 -4:2005 , as applicable.  
Compliance is checked by measurement.  
29.2.3  Creepage distances  of reinforced insulation  shall be at least double those specified 
for basic insulation  in Table 17 , excluding its NOTE 1 and NOTE 2, or Table 2 of 
IEC 60664 -4:2005 , as applicable.   – 114 – IEC 60335- 1:2020 ©  IEC 20 20        Compliance is checked by measurement.  
29.2.4  Creepage distances  of functional insulation  shall be not less than those specified 
in Table 18. However, if the working voltage  is periodic and has a frequency that exceeds 
30 kHz, the creepage distances shall also be determined from Table 2 of IEC 60664-4 :2005 . 
These values shall be used  instead if they exceed the values in Table 18. 
The creepage distances  may be reduced if the appliance complies with Clause  19 with the 
functional in sulation  short -circuited.  
Table 18 – Minimum creepage distances for functional insulation 
Working voltage Creepage distance 
V mm 
 Pollution degreea 
1 2 3 
Material group  Material group  
I II IIIa/IIIb  I II IIIa/IIIb b 
   ≤ 10 0,08  0,4 0,4 0,4 1,0 1,0 1,0 
50   0,16  0,56  0,8 1,1 1,4 1,6 1,8 
125   0,25  0,71  1,0 1,4 1,8 2,0 2,2 
250   0,42  1,0 1,4 2,0 2,5 2,8 3,2 
400 c   0,75  1,6 2,2 3,2 4,0 4,5 5,0 
500   1,0 2,0 2,8 4,0 5,0 5,6 6,3 
> 630  and ≤ 800  1,8 3,2 4,5 6,3 8,0 9,0 10,0  
> 800  and ≤ 1 000  2,4 4,0 5,6 8,0 10,0  11,0  12,5  
> 1 000  and ≤ 1 250  3,2 5,0 7,1 10,0  12,5  14,0  16,0  
> 1 250  and ≤ 1 600  4,2 6,3 9,0 12,5  16,0  18,0  20,0  
> 1 600  and ≤ 2 000  5,6 8,0 11,0  16,0  20,0  22,0  25,0  
> 2 000  and ≤ 2 500  7,5 10,0  14,0  20,0  25,0  28,0  32,0  
> 2 500  and ≤ 3 200  10,0  12,5  18,0  25,0  32,0  36,0  40,0  
> 3 200  and ≤ 4 000  12,5  16,0  22,0  32,0  40,0  45,0  50,0  
> 4 000  and ≤ 5 000  16,0  20,0  28,0  40,0  50,0  56,0  63,0  
> 5 000  and ≤ 6 300  20,0  25,0  36,0  50,0  63,0  71,0  80,0  
> 6 300 and ≤ 8 000  25,0  32,0  45,0  63,0  80,0  90,0  100,0  
> 8 000  and ≤ 10 000  32,0  40,0  56,0  80,0  100,0  110,0  125,0  
> 10 000  and ≤ 12 500  40,0  50,0  71,0  100,0  125,0  140,0  160,0  
NOTE  1 For PTC  heating elements , the creepage distances over the surface of the PTC material need not be 
greater than the associated clearance  for working voltages less than 250  V and for pollution degrees 1 and 2. 
However, the creepage distances between terminations are those specified in the table.  
NOTE  2 For glass, ceramics and other inorganic insulating materials that do not track, creepage distances need 
not be greater than the associated clearance . 
NOTE  3 For working voltages  > 10 V and ≤  630 V, if the voltage is not specified in the table, the values of 
creepage distances can be found by interpolation.  IEC 60335- 1:2020 © IEC 2020 – 115 –         a For tracks on printed wiring boards under pollution degree 1 and pollution degree 2 conditions, the values 
specified in Table F.4 of IEC 60664-1 :2007 apply.  For voltages less than 100 V, the values shall  not be less 
than those specified for 100  V. 
b  Mater ial group IIIb is allowed if the working voltage  does not exceed 50  V. 
c The working voltage between phases for appliances having a rated voltage in the range of 380 V to 415 V is 
considered to be 400 V. 
 
Compliance is checked by measurement.  
29.3  Supplementary insulation and reinforced insulation shall have adequate thickness, 
or have a sufficient number of layers, to withstand the electrical stresses that can be expected 
during the use of the appliance.  
Compliance is checked : 
– by measurement, in accordance with 29.3.1, or  
– by an electric strength test in accordance with 29.3.2, if the insulation consists of more than 
one separate layer, other than natural mica or similar flaky material, or  
– for insulation, other than single layer internal wiring insulation, by an assessment of the 
thermal quality of the material combined with an electric strength test, in accordance with 29.3.3 and for accessible parts of reinforced insulation consisting of a single layer, by 
measure ment in accordance with 29.3.4 , or 
– by an assessment of the thermal quality of the material according to 29.3.3 combined with 
an electric strength test in accordance with 23.5 , for each single layer internal wiring 
insulation touching each other, or  
– as specified in Subclause  6.3 of IEC 60664-4 :2005  for insulation that is subjected to any 
periodic voltage having a frequency that exceeds 30  kHz.  
29.3.1  The thickness of the insulation shall be at least : 
– 1 mm for supplementary insulation ; 
– 2 mm for reinforced insulation. 
29.3.2  Each layer of material shall withstand the electric strength test of 16.3 for 
supplementary insulation . Supplementary insulation shall consist of at least 2 layers of 
material and reinforced insulation of at least 3 layers.  
29.3.3  The insulation is subjected to the dry heat test Bb of IEC  60068-2- 2 for 48 h at a 
temperature of 50 K in excess of the maximum temperature rise measured during the test of 
Clause  19. At the end of the period, the insulation is subjected to the electric strength test of 
16.3 at the conditioning temperature and also after it has cooled down to room temperature . 
If the temperature rise of the insulation measured during the tests of Clause  19 does not exceed 
the value specified in Table 3, the test of IEC 60068-2- 2 is not carried out. 
29.3.4  The thickness of the accessible parts of reinforced insulation consisting of a single 
layer shall not be less than those specified in Table 19.  – 116 – IEC 60335- 1:2020 ©  IEC 20 20        Table 19 – Minimum thickness for accessible parts  
of reinforced insulation consisting of a single layer 
Rated voltage  Minimum thickness of single layers used for accessible parts of reinforced 
insulation  
V mm 
 Overvoltage category  
I II III 
≤ 50 0,01  0,04  0,1 
> 50 and ≤ 150 0,1 0,3 0,6 
> 150 and ≤ 300 0,3 0,6 1,2 
 
NOTE  The values in Table 19 cover clearances  through a possible hole in the insulation and align with 
IEC 60664-1 :2007 Table F.2 for homogenous field conditions. The creepage distance  through a possible hole is not 
consi dered relevant because it is only stressed when the second electrode (human body) is present.  
30 Resistance to heat and fire 
30.1  External parts of non- metallic material, parts of insulating material supporting  live parts 
including connections, and parts of thermoplastic material providing supplementary insulation  
or reinforced insulation  shall be sufficiently resistant to heat if their deterioration could cause 
the appliance to fail to comply with this standard.  
This requ irement does not apply to : 
– the insulation or sheath of flexible cords or internal wiring; 
– those parts of coil formers that do not support or retain terminals in position;  
– parts of ceramic material.  
Compliance is checked by subjecting the relevant part to t he ball pressure test of 
IEC 60695 -10-2. 
The test is carried out at a temperature of 40 °C ± 2 °C plus the maximum temperature rise 
determined during the test of Clause  11, but it shall be at least : 
– 75 °C ± 2 °C, for external parts;  
– 125 °C ± 2 °C, for parts supporting  live parts. 
However, for parts of thermoplastic material  providing supplementary insulation or reinforced 
insulation,  the test is carried out at a temperature of 25 °C ± 2 °C plus  the maximum 
temperature rise determined during the tests of Clause  19, if this i s higher. The temperature 
rises obtained during the test s of 19.4  and 19.5 are not taken into account provided that the 
test is terminated by the operation of a non- self-resetting protective device  and it is 
necessary to remove a cover or use a tool to reset it.  
NOTE  The selection and sequence of tests for resistance to heat are shown in Figure O.1  of informative Annex O . 
30.2  Parts of non- metallic material shall be resistant to ignition and spread of fire.  
The requirement does not apply to parts having a mass not exceeding 0,5  g which are 
considered insignificant parts, provided the cumulative effect of insignificant parts located within 
3 mm of each other is unlikely to propagate flames that originate inside the appliance by 
propagating flames from one insignificant part to another.  IEC 60335- 1:2020 © IEC 2020 – 117 –         The requirement also does not apply to decorative trims, knobs and other parts unlikely to be 
ignited or to propagate flames that originate inside the appliance.  
Compliance is checked by the test of 30.2.1. In addition : 
– for attended appliances, 30.2.2 is applicable;  
– for unattended appliances, 30.2.3 is applicable. 
Appliances for remote operation  are considered to be appliances that are operated while 
unattended and consequently they are subjected to the test of 30.2.3. 
For parts of the appliance that are con nected to the supply mains during the charging period, 
30.2.3 applies.  
For the base material of printed circuit boards, compliance is checked by the test of 30.2.4 . 
The tests are carried out on parts of non- metallic material that have been removed from the 
appliance. When the glow -wire test is carried out, the parts are placed in the same orientation 
as they would be in normal use.  
NOTE  1 For parts that have been removed, it is the intention that IEC  60695 -2-11:2014,  4.3.c) applies, which states 
"remove the part under examination in its entirety and test it separately ". 
These tests are not carried out on the insulation of wires.  
NOTE  2 The selection and sequence of tests for resistance to fire are shown in Figure O. 2 to Figure O.4  of 
informative Annex O . 
30.2.1  Parts of non- metallic material are subjected to the glow -wire test of 
IEC 60695 -2-11:201 4, which is carried out at 550 °C. However, the glow -wire test is not carried 
out on parts of material classified as having a glow- wire flammability index (GWFI) according 
to IEC 60695 -2-12 of at least 550  °C. 
If the glow -wire flammability index (GWFI) is not available for a sample with a thickness within 
± 0,1 mm of the relevant part , then the test sample shall have a thickness equal to the nearest 
preferred value specified in IEC 60695 -2-12 that is no thicker than the relevant part.  
The glow -wire test is also not carried out on parts of material classified at least HB40 according 
to IEC 60695 -11-10 provided that the test sample used for the classification was no thicker than 
the relevant part of the appliance.  
Parts for which the glow -wire test cannot be carried out, such as those made of soft or foamy 
material, shall meet the require ments specified in ISO 9772 for material classified HBF, the test 
sample used for the classification being no thicker than the relevant part of the appliance.  
30.2.2  For appliances that are operated while attended, parts of non- metallic material 
supporting curren t-carrying connections, such as switch contacts and similar contacts in other 
components and parts of non- metallic material within a distance of 3 mm of such connections 
are subjected to the glow -wire test of IEC 60695 -2-11:201 4. 
The tip of the glow- wire should be applied to the part in the vicinity of the connection.  
The test severity is : 
– 750 °C, for connections that carry a current exceeding 0,5  A during normal operation , 
– 650 °C, for other connections.  
Where a non -metallic material is within a distance of 3 mm of a current -carrying  connection, but 
is shielded from the connection by a differen t material, the glow -wire test of  – 118 – IEC 60335- 1:2020 ©  IEC 20 20        IEC 60695 -2-11:201 4 is carried out at the relevant test severity with the tip of the glow -wire 
applied to the interposed shielding material with the shielded material in place and not directly 
to the shielded material.  
How ever, the glow -wire test of IEC 60695-2- 11:201 4 is not carried out on parts of material 
classified as having a glow -wire flammability index (GWFI) according to IEC  60695-2- 12 of at 
least : 
– 750 °C, for connections which carry a current exceeding 0,5  A during normal operation , 
– 650 °C, for other connections.  
The glow -wire test of IEC 60695-2- 11:201 4 is also not carried out on small parts . These parts 
shall : 
– comprise material having a glow -wire flammability index (GWFI) of at least 750  °C, or  
650 °C as appropriate ; or 
– comply with the needle -flame test (NFT) of normative Annex  E; or  
– comprise material classified as V -0 or V -1 according to IEC 60695- 11-10 provided that the 
test sample used for the classification was no thicker than the relevant part of the appliance . 
If the glow -wire flammability index (GWFI) is not available for a sample with a thickness within 
± 0,1 mm of the relevant part, then the test sample shall have a thickness equal to the nearest  
preferred value specified in IEC 60695 -2-12 that is no thicker t han the relevant part . 
The glow -wire test of IEC 60695-2- 11:201 4 is not applicable to : 
– hand -held appliances; 
– appliances that have to be kept switched on by hand or foot;  
– appliances that are continuously loaded by hand;  
– parts supporting welded connections and parts within a distance of 3  mm of these 
connections;  
– parts supporting connections in low -power circuits described in 19.11.1 and parts within a 
distance of 3 mm of these connections;  
– soldered connections on printed circuit boards and parts within a distance of 3 mm of these 
connections;  
– connections on small components on printed circuit boards, such as diodes, transistors, 
resistors, inductors, integrated circuits and capacitors not directly connected to the supply mains, and parts within a distance of 3 mm of these connections.  
NOTE  Some applications of the term "within a distance of 3  mm" are shown in Figure O.5  of informative Annex  O. 
30.2.3  Appliances that are operated while unattended are tested as specified in 30.2.3.1 and 
30.2.3.2. However, the tests are not applicable to : 
– parts supporting welded connections and parts within a distance of 3 mm of these 
connections;  
– parts supporting connections in low -power circuits described in 19.11.1 and parts within a 
distance of 3 mm of these connections;  
– soldered connections on printed circuit boards and parts within a distance of 3 mm of these 
connections;  
– connections on small components on printed circuit boards, such as diodes, transistors, 
resistors, inductors, integrated circuits and capacitors not directly connected to the supply 
mains, and parts within a distance of 3 mm of these connections.  
NOTE  Some applications of the term "within a distance of 3  mm" are shown in Figure O.5  of informative Annex  O. IEC 60335- 1:2020 © IEC 2020 – 119 –         30.2.3.1  Parts  of non- metallic  material supporting connections , such as switch contacts and 
similar contacts in other components, that carry a current exceeding 0,2  A during normal 
operation , and parts of non- metallic  material, other than small parts , within a distance of 3 mm 
of such connections, are subjected to the glow -wire test of IEC  60695 -2-11:201 4 with a test 
severity of 850  °C. 
The tip of the glow- wire should be applied to the part in the vicinity of the connection.  
Where a non -metallic mater ial is within a distance of 3 mm of a current -carrying  connection, but 
is shielded from the connection by a different material, the glow -wire test of 
IEC 60695 -2-11:201 4 is carried out at the relevant temperature with the tip of the glow- wire 
applied to the interposed shielding material with the shielded material in place and not directly 
to the shielded material.  
However, the glow- wire test of IEC 60695 -2-11:201 4 with a test severity of 850 ° C is not carried 
out on parts of material classified as having a glow- wire flammability index (GWFI) of at least 
850 °C according to IEC 60695-2- 12. 
If the glow -wire flammability index (GWFI) is not available for a sample with a thickness within 
± 0,1 mm of the relevant part, then the test sample shall have a thickness equal to the nearest  
preferred value specified in IEC 60695 -2-12 that is no thicker than the relevant part . 
30.2.3.2  Parts of non- metallic material supporting connections, such as switch contacts and 
similar contacts in other components  and parts of non- metallic material within a distance of 
3 mm of such connections are subjected to the glow -wire test of IEC  60695 -2-11:201 4. 
The tip of the glow- wire should be applied to the part in the vicinity of the connection.  
The test severity is : 
– 750 °C, for connections that carry a current exceeding 0,2 A during normal operation ; 
– 650 °C, for other connections.  
Where a non -metallic material is within a distance of 3 mm of a current -carrying  connection, but 
is shielded from the connection by a different material, the glow -wire test of 
IEC 60695 -2-11:201 4 is carried out at the relevant test severity with the tip of  the glow -wire 
applied to the interposed shielding material with the shielded material in place and not directly to the shielded material.  
However, the glow -wire test with a test severity of 750  °C or 650 °C as appropriate, is not 
carried out on parts of material fulfilling both or either of the following classifications:  
– a glow -wire ignition temperature (GWIT) according to IEC 60695-2- 13 of at least;  
• 775 °C, for connections that carry a current exceeding 0,2  A during normal operation ; 
• 675 °C, for other connections.  
– a glow -wire flammability index (GWFI) according to IEC 60695-2- 12 of at least;  
• 750 °C, for connections that carry a current exceeding 0,2  A during normal operation ; 
• 650 °C, for other connections.  
If the glow -wire ignition temperature (GWIT) is not available for a sample with a thickness within 
± 0,1 mm of the relevant part, then the test sample shall have a thickness equal to the nearest  
preferred value specified in IEC 60695 -2-13 that is no thicke r than the relevant part . 
If the glow -wire flammability index (GWFI) is not available for a sample with a thickness within 
± 0,1 mm of the relevant part, then the test sample shall have a thickness equal to the nearest 
preferred value specified in IEC 60695-2- 12 that is no thicker than the relevant part.   – 120 – IEC 60335- 1:2020 ©  IEC 20 20        The glow -wire test of IEC  60695-2- 11:201 4 with a test severity of 750 ° C or 650 ° C as 
appropriate, is also not carried out on small parts . These parts  shall : 
– comprise material having a glow -wire ignition temperature (GWIT) of at least 775 °C or 
675 °C as appropriate ; or 
– comprise material having a glow -wire flammability index (GWFI) of at least 750  °C or 650 °C 
as appropriate ; or 
– comply with the needle -flame test (NFT) of normative Annex  E; or  
– comprise material classified as V -0 or V -1 according to IEC 60695- 11-10 provided that the 
test sample used for the classification was no thicker than the relevant part of the appliance.  
A consequential needle- flame test (NFT) in accordance with normative Annex  E is applied to 
non- metallic parts that encroach within the envelope of a vertical cylinder having a diameter of 
20 mm and a height of 50 mm, placed above the centre of the connection zone and on top of 
the non- metallic parts that are supporting current -carrying connections, and parts of non-
metallic material within a distance of 3 mm of such connections if these parts are those : 
– that withstood the glow -wire test of IEC  60695-2- 11:201 4 with a test severity of 750  °C or 
650 °C as appropriate, but that during the test produce a flame that persists for longer than 
2 s; or 
– that comprised material having a glow -wire flammability index (GWFI) of at least 750  °C, or 
650 °C as appropriate ; or 
– small parts, that comprised material having a glow -wire flammability index (GWFI) of at 
least 750  °C, or 650  °C as appropriate ; or  
– small parts for which the needle- flame test (NFT) of normative  Annex  E was applied ; or 
– small parts  for which a material classification of V -0 or V -1 was applied.  
NOTE  An example of the placement of the vertical cylinder is shown in Figure 12. 
However, the consequential needle- flame test is not carried out on non -metallic parts, including 
small parts , within the cylinder that are parts: 
– having a glow -wire ignition temperature (GWIT) of at least 775 °C, or 675  °C as appropriate; 
or 
– comprising material classified as V -0 or V -1 according to IEC 60695- 11-10 provided that the 
test sample used for the classification was no thicker than the relevant part of the appliance; 
or 
– shielded by a flame barrier that meets the needle -flame test (NFT) of normative Annex  E or 
that comprises material classified as V -0 or V -1 according to IEC 60695- 11-10 provided that 
the test sample used for the classification was no thicker than the relevant part of the appliance.  
There shall be no battery in the area of the vertical cylinder used for the consequential needle 
flame test , unless the battery  is shie lded by a barrier that meets the needle flame test of 
normative Annex  E or that comprises material classified as V -0 or V -1 according to 
IEC 60695 -11-10, provided that the test sample used for the classification was no thicker than 
the relevant part of the appliance.  
30.2.4  The base material of printed circuit boards is subjected to the needle- flame test (NFT) 
of normative  Annex  E. The flame is applied to the edge of the board where the heat sink effect 
is lowes 
t when the board is positioned as in normal use.  
NOTE  The test can be carried out on a printed circuit board on which components are mounted. However, ignition 
of a component is disregarded.  
The needle- flame test (NFT) of normative  Annex  E is not carried out  on: 
– printed circuit boards of low -power circuits described in 19.11.1 ; IEC 60335- 1:2020 © IEC 2020 – 121 –         – the printed circuit boards in : 
• a metal enclosure that confines flames or burning droplets ; 
• hand -held appliances; 
• appliances that have to be kept switched on by hand or foot ; 
• appliances that are continuously loaded by hand . 
– a base material classified as V -0 acc ording to IEC 60695 -11-10 or VTM -0 according to 
ISO 9773 , provided that the test sample used for the classification was no thicker than the 
printed circuit board.  
31 Resistance to rusting  
Ferrous parts, the rusting of which might cause the appliance to fail to comply with this standard, 
shall be adequately protected against rusting.  
Unless otherwise specified  in the relevant part 2, the appliance is deemed to comply with the 
requirement without testing.  
32 Radiation, toxicity and similar hazards  
32.1  Appliances shall not emit harmful radiation or present a toxic or similar hazard due to 
their operation in normal use.  
Unless otherwise specified  in the relevant part 2, the appliance is deemed to comply with the 
requirement without testing.  
32.2  Appliances shall not present an optical radiation hazard due to their operation in normal 
use. 
This requirement does not apply to lamps and lamp systems that comply with 24.1.10 . 
Compliance is checked as follows with the appliance supplied at rated voltage . 
Radiation assessment is performed at or recalculated to 200 mm distance or at the fixed use 
distance indicated in the instructions for use, following the measurement procedure described in IEC 62471:2006.  
If a lamp or lamp system is intended to illuminate objects, it shall be assessed at the GLS assessment distance  which produces a luminance of 500 lux as described in IEC 62471:2006.  
The appliance shall comply with the exempt group classification requirements of IEC 62471:2006 regarding actinic ultraviolet hazard (E
S) and near -UV hazard (EUVA). 
NOTE  To avoid errors associated with low signal to noise ratio from spectroradiometers, handheld radiometers with 
specialized detectors sensitive to either the actinic UV or UV -A region can be used for these measurements.   – 122 – IEC 60335- 1:2020 ©  IEC 20 20        
 
Key 
C circuit of Figure 4 of IEC  60990:2016  
1 accessible part  
2 inaccessible metal part  
3 basic insulation  
4 supplementary insulation  
5 double insulation 
6 reinforced insulation  
Figure 1 – Circuit diagram for leakage current measurement at operating temperature  
for single -phase connection of class II appliances and for parts of class ll construction 
IEC 60335- 1:2020 © IEC 2020 – 123 –          
Key 
C circuit of Figure 4 of IEC  60990:2016  
NOT E For class 0I appliances and class I appliances, C  can be replaced by a low impedance ammeter  responding 
to the rated frequency of the appliance. 
Figure 2 – Circuit diagram for leakage current measurement at operating temperature  
for single- phase connection of other than class II  appliances 
 or parts of class ll construction  
 – 124 – IEC 60335- 1:2020 ©  IEC 20 20        
 
Key Connections and supplies  
C circuit of Figure 4 of IEC  60990:2016  L1, L2, L3, N  supply voltage with neutral  
1 accessible part  PE protective earth conductor  
2 inaccessible metal part  Z IT system neutral to earth high impedance  
3 basic insulation   
4 supplementary insulation   
5 double insulation  
NOTE  If the test laboratory is supplied from a TN or TT distribution system , then Z will be zero. Consequently, 
always connecting "C" to the neutral conductor will ensure reproducibility of the test result regardless of the type of 
distribution system (TN, TT or IT) used by the test laboratory and will cover the most onerous condition likely to be 
encountered during normal use of the appliance. 
Figure 3 – Circuit diagram for leakage current measurement at operating temperature  
for three- phase  with n eutral  class II appliances and for parts of class ll construction 
IEC 60335- 1:2020 © IEC 2020 – 125 –         
 
Key Connections and supplies  
C circuit of Figure 4 of IEC  60990:2016  L1, L2, L3, N Supply voltage with neutral  
1 accessible part  PE protective earth conductor  
2 basic insulation  Z IT system neutral to earth high impedance  
NOTE  1 For class 0I appliances and class I appliances, C  can be replaced by a low impedance ammeter  
responding to the rated frequency of the appliance.  
NOTE 2  If the test laboratory is supplied from a TN or TT distribution system,<  then Z will be zero. Consequently, 
always connecting "C" to the ne utral conductor will ensure reproducibility of the test result regardless of the type of 
distribution system (TN, TT or IT) used by the test laboratory and will cover the most onerous condition likely to be 
encountered during normal use of the appliance. 
Figure 4 – Circuit diagram for leakage current measurement at operating temperature  
for three- phase  with neutral  appliances other than those of class II  or parts of class ll 
construction 
 – 126 – IEC 60335- 1:2020 ©  IEC 20 20          
a) Example of a small part  b) Example of a small part  
 
c) Example of a part that is not a small part  
Key 
S surface  
NOTE  The small and large circles in examples A, B and C are 8 mm and 15 mm in diameter respectively.  
Figure 5 – Small part  
 
D is a point farthest from the supply source where the maximum power delivered to external load exceeds 15 W.  
A and B are points closest to the supply source where the maximum power delivered to external load does not exceed 
15 W. These are low -power points.  
Points A and B are separately short- circuited to C.  
The fault conditions a) to g) specified in 19.11.2 are applied individually to Z1, Z2, Z3, Z6 and Z7, where applicable.  
Figure 6 – Example of an electronic circuit with low -power points  
IEC 60335- 1:2020 © IEC 2020 – 127 –         Dimensions in millimetres  
 
Key 
A insulating material  
B spring with a constant suitable for providing a push force as specified in 22.11 on the test finger nail  
C loop  
Figure 7 – Test finger nail   
 – 128 – IEC 60335- 1:2020 ©  IEC 20 20        Dimensions in millimetres  
 
Key 
A axis of oscillation  
B oscillating frame 
C counterweight  
D sample  
E adjustable carrier plate  
F adjustable bracket  
G load  
Figure 8 – Flexing test apparatus  
 
IEC 60335- 1:2020 © IEC 2020 – 129 –         ACCEPTABLE CONSTRUCTIONS  
  
Construction showing studs securely attached to the appliance  
  
Construction showing part of appliance of insulating 
material and so shaped that it obviously forms part of a 
cord clamp.  Construction showing one of the clamping members is 
fixed to the appliance 
NOTE  1 Clamping screws can  screw into threaded holes in the appliance or pass through holes where they are 
secured by nuts.  
UNACCEPTABLE CONSTRUCTIONS  
  
Construction showing no part securely fixed to the appliance  
NOTE  2 Clamping screws can  screw into threaded holes in the appliance or pass through holes where they are 
secured by nuts.  
 
Figure 9 – Constructions of cord anchorages 
 
 – 130 – IEC 60335- 1:2020 ©  IEC 20 20         
Key 
1 part providing earthing continuity  
2 part providing or transmitting contact pressure 
Figure 10 – An example of parts of an earthing terminal  
IEC 60335- 1:2020 © IEC 2020 – 131 –         
 
Key 
1 accessible unearthed metal part  
2 enclosure  
3 accessible earthed metal part  
4 inaccessible unearthed metal part  
The live parts L1 and L2 are separated from each other and partially surrounded by a plastic enclosure containing 
apertures, partially by air and are in contact with solid insulation. A piece of inaccessible metal is incorporated inside 
the construction. There are two metal covers, one of which is earthed.  
Type of insulation  Clearance  
Basic insulation  L1A 
L1D 
L2F 
Functional insulation L1L2 
Supplementary insulation  DE 
FG 
Reinforced insulation  L1K 
L1J 
L2I 
L1C 
NOTE  If the clearances L1D or L2F meet the clearance requirements for reinforced insulation , the clearances  
DE or FG of supplementary insulation  are not measured.  
Figure 11 – Examples of clearances 
 – 132 – IEC 60335- 1:2020 ©  IEC 20 20        
 
Key 
A connection zone 
B non- metallic material  
C non- metallic material  
D non- metallic material  
NOTE  1 The placement of the cylinder is shown with respect to example 1 in Figure O.5 . 
NOTE  2 If C flames for longer than 2  s during the glow- wire test, then the cylinder is assumed to be located at the 
upper boundary of C. Consequently parts B and D are subjected to the needle- flame test.  
If B flames for longer than 2 s during the glow -wire test, then the cylinder is assumed to be located on top of B. 
Consequently, D is subjected to the needle- flame test.  
NOTE  3 In some constructions, D can be another part of the same moulding as B or C. Therefore, if B or C flame 
for longer than 2 s during the glow- wire test, the material used for B or C that is within the cylinder, represented by 
D, is also subjected to the needle- flame test.  
Figure 12 – Example of the placement of the cylinder  
IEC 60335- 1:2020 © IEC 2020 – 133 –         Dimensions in millimetres  
 
Figure 13 – Small parts cylinder  
 – 134 – IEC 60335- 1:2020 ©  IEC 20 20        
 
Key 
T1 to T2 low temperature range  
T2 to T3 standard temperature range  
T3 to T4 high temperature range  
ORC  operating region (current)  
Icmax maximum charging current  
Ic charging current 
ORV  operating region (voltage)  
Vcmax upper limit charging voltage  
Vc charging voltage  
Tcell c ell surface temperature  
Figure 14 – Example of a specified operating region  
of a lithium -ion cell during charging  
 
IEC 60335- 1:2020 © IEC 2020 – 135 –         Annex  A 
(informative)  
 
Routine tests  
A.1 Overview  
Routine tests are intended to be carried out by the manufacturer on each appliance to detect a 
production variation that could impair safety. They are normally carried out on the complete appliance after assembly but the manufacturer may perfo rm the tests at an appropriate stage 
during production, provided that later manufacturing processes do not affect the results.  
Components are not subjected to these tests if they have been previously subjected to routine 
tests during their manufacture.  
The manufacturer may use a different routine test procedure provided that the level of safety is 
equivalent to that provided by the tests specified in this annex.  
These tests are the minimum considered necessary to cover essential safety aspects. It is the 
manufacturer’s responsibility to decide if additional routine tests are necessary. It may be 
determined from engineering considerations that some of the tests are impracticable or 
inappropriate and therefore need not be carried out.  
If a product fails any of the tests, it is to be retested after rework or adjustment.  
A.2 Earth continuity test  
A current of at least 10  A, derived from a source having a no -load voltage not exceeding 12 V 
(AC or DC), is passed between each of the accessible earthed metal parts and for: 
– class 0I appliances , and for class I appliances intended to be permanently connected to 
fixed wiring, the earthing terminal;  
– other class I appliances: 
• the earthing pin or earthing contact of the plug;  
• the earthing pin of the appliance inlet.  
The voltage drop is measured and the resistance is calculated and shall not exceed  for: 
– appliances having a supply cord , 0,2  Ω, or 0,1  Ω plus the resistance of the supply cord;  
– other appliances, 0,1  Ω. 
The duration of the current flow is that required to enabl e the voltage drop to be measured.  
A.3 Electric strength test  
The insulation of the appliance is subjected to a voltage of substantially sinusoidal waveform having a frequency of approximately 50  Hz or 60  Hz for 1  s. The value of the test voltage and 
the points of application are shown in Table A. 1.  – 136 – IEC 60335- 1:2020 ©  IEC 20 20        Table A. 1 – Test voltages 
Points of application  Test voltage  
V 
Class 0 appliances, Class 0I appliances, Class I 
appliances and Class II appliances  Class III appliances  
Rated voltage  
≤ 150 V  > 150 V  
Between live parts and 
accessible metal parts  
separated from live parts 
by    
• basic insulation only   800 1 000  400 
• double or reinforced  
  insulation a, b  2 000  2 500  – 
a This test is not applicable for class 0 appliances.  
b For class 0I appliances and class I appliances, this test need not be carried out on parts of class II  
construction if the test is considered to be inappropriate.  
 
It may be necessary for the appliance to be in operation during the test to ensure that the test 
voltage is applied to all relevant insul ation, for example, heating elements controlled by a relay.  
Instead of being subjected to an AC voltage, the insulation may be subjected to a DC voltage 
of 1,5  times the value shown in the table. An AC voltage having a frequency up to 5  Hz is 
considered to  be a DC voltage.  
No breakdown shall occur. Breakdown is assumed to occur when the current in the test circuit exceeds 5  mA. However, this limit may be increased up to 30  mA for appliances with a high 
leakage current.  
The circuit used for the test should incorporate a current sensing device that trips when the current exceeds the limit. The high voltage transformer should be capable of maintaining the 
specified voltage at the limiting current.  
A.4 Functional test  
The correct functioning of an appliance is checked by inspection or by an appropriate test if the incorrect connection or adjustment of components has safety implications.  
NOTE  Examples are verification of the correct direction of motor rotation and the appropriate operation of interlo ck 
switches. This does not require testing of thermal controls or protective devices. 
 IEC 60335- 1:2020 © IEC 2020 – 137 –         Annex  B 
(normative)  
 
Battery -operated appliances, separable batteries and detachable  
batteries for battery- operated  appliances  
The following modifications to this standard are applicable to : 
– battery -operated appliances  and remote controls employing non-rechargeable batteries  
(primary batteries);  
– battery -operated appliances and remote controls employing batteries  that are 
rechargeable (secondary batteries ); 
– detachable batteries and separable batteries  for battery- operated appliances . 
The clause numbers in this Annex refer to the clause numbers in the main part of this standard 
that are modified or not applicable. Clauses that are additional to the clauses in the main part 
of this  standard are identified by adding the Annex letter with the numbering starting at 1.  
NOTE 1  This annex does not apply to battery chargers ( IEC 60335-2- 29) (See Figure B.1 e). When used in 
conjunction with the word charger, battery is not a defined term so is not bolded.  
NOTE 2  When supplied in parts, the complete appliance is the detachable power supply part : 
– plus the part of the appliance containing the  battery  and the battery charging circuitry ( Figure B.1  b); 
– with the battery  charging circuitry plus the part of the appliance containing the battery  (see Figure B.1  c and d); 
or 
– with the battery  charging circuitry plus the separable battery and the part of the appliance performing the 
intended function (see Figure B.1 f). 
An overview on the different configurations is given in Figure B.1.  
NOTE 3  As the requirements in this annex are based on battery systems that use lithium- ion chemistry , other 
metal -ion and newer chemistries can have characteristics and performance not fully contemplated by these 
requirements or those of the referenced battery standard.  
3 Terms and definitions  
B.3.1 Definitions relating to physical characteristics  
B.3.1.1 
normal operation  
battery -operated appliances  are operated under the following conditions:  
– for appliances operated with detachable batteries  or separable batteries that are 
disconnected from the appliance for charging purposes , the appliance is operated to perform 
its intended function with a battery  that is fully charged . The battery  being the model or 
type reference of the battery  provided or indicated in the instructions;  
– for appliances operated with integral batteries or separable batteries not disconnected 
from the appliance for charging purposes , and that cannot perform their intended function 
while the batteries  are being charged, the appliance is operated to perform its intended 
function with a battery  that is fully charged ; 
– for appliances operated with batteries  that are replaceable, including integral batteries 
that are replaceable,  or non-rechargeable batteries, the appliance is operated to perform 
its intended function with the artificial source described in B.5.3 with the specified upper 
limit short circuit current capacity Isc (high) as indicated in Table B. 1. 
Note 1 to entry:  Operation of the appliance to perform its intended function is specified in the relevant part 2.   – 138 – IEC 60335- 1:2020 ©  IEC 20 20        B.3.6 Definitions relating to parts of an appliance  
B.3.6.1  
non-rechargeable battery 
battery  that is supplied in a fully charged  state and cannot be recharged thereafter 
5 General conditions for the tests  
5.2 The tests of subclauses B.19.1 to B.19.6 may be carried out on separate samples.  
5.8.1 This subclause is not applicable. 
5.8.2 This subclause is not applicable.  
5.8.3 This subclause is not applicable.  
5.8.4 This subclause is not applicable.  
B.5.1  Before starting a test requiring a battery that is  fully charged, the battery  shall be fully 
charged  and then shall be disconnected from the charging source and allowed to rest for at 
least 2  h but no more than 6 h. 
B.5.2 Whenever a rated voltage  is specified, a battery  that is  fully charged shall be used.  
For battery- operated appliances , where the supply terminals for the connection of the battery 
have no indication of polarity, the more unfavourable polarity shall be appli ed unless such a 
connection is unlikely to occur due to the construction of the appliance.  
B.5.3 Where it is specified in the requirements that the battery  provided with or intended for 
the appliance may be replaced with an artificial source, that source shall consist of a DC power 
supply or a specially constructed battery , the output of each having the characteristics 
described in Table B. 1 for the relevant battery  type.  IEC 60335- 1:2020 © IEC 2020 – 139 –         Table B. 1 – Artificial source characteristics 
Battery type  Initial open 
circuit 
voltage  Isc a (low)  
 Isc a 
(high)  Minimum capacity  
(Informative) 
IEC 
References  b V A A Ah c 
± 10 % +0 % +25 %  
 −25 % −0 %  
Rechargeable  Fully -
charged 
battery  
voltage  0,5 × Isc of 
battery  
provided  2,0 × Isc of 
battery  
provided  300 % of capacity of 
battery  provided 
measured at 1 A and 
0,9 V/cell cut-off 
Non-rechargeable 
AAAd 1,5 3 10 0,5 LR03  
Non-rechargeable AAd 1,5 5 15 1,0 LR6 
Non-rechargeable Cd 1,5 5 15 3,0 LR14  
Non-rechargeable Dd 1,5 6 20 10 LR20  
Non-rechargeable 
PP3d (9 V) 9,0 0,6 6 0,5 6LR61  
Non-rechargeable 
(other)  Nominal 
battery voltage  0,5 × I
sc of 
battery  
provided  2,0 × Isc of 
battery  
provided  200 % of capacity of 
battery provided 
measured at 1 A and 
0,9 V/cell cut-off - 
NOTE  1 Isc limits are specified for those batteries  likely to be replaced with others of the same type but of 
differing performance.  
NOTE  2 The specified Ah values are based upon nominal 1 A discharge current with a 0,9  V/cell end- of-
discharge voltage except for PP3 (9 V), which is based upon 0,1  A discharge current with a 0,9 V/cell end- of-
discharge voltage.  
NOTE  3 As used in this table, "provided" means either the battery  that is provided with the appliance or , if not 
provided , the battery  that is intended or specified to be used with the appliance.  
a The short circuit current is measured after 1  s ± 0,2 s into a resistance of 10 mΩ ± 2 mΩ. Care shall be taken 
to ensure that self- heating of the resistance is managed to minimize the variability on the current during the 
tests.  
b References are taken from IEC  60086- 1. 
c If the measured capacity is less than 50 % of the capacity specified by the battery  manufacturer, calculation 
of minimum capacity shall be based on the capacity specified by the battery  manufacturer instead of 
measurement.  
d The non- rechargeable types specified are for alkaline types only . 
 
6 Classification  
6.1 Battery -operated appliances  without a supply connection or a functional earth 
connection are not classified with respect to protection against electric shock.  
NOTE  Potential for electric shock hazard is considered to exist only between parts of opposite polarity with no 
reference to earth.  
Compliance is checked by inspection and the relevant tests.  
7 Marking and instructions  
7.1 Battery -operated appliances  and remote controls containing batteries  shall be marked 
with the:  – 140 – IEC 60335- 1:2020 ©  IEC 20 20        – name, trade mark or identification mark of the manufacturer or  responsible vendor;  
– model or type reference;  
– IP number according to degree of protection against ingress of water, other than IPX0;  
– type reference of the battery if the battery  is either not recharged in the appliance or is 
non- rechargeable.  
Appliances incorporating batteries that are replaceable shall be marked with the battery  type 
reference, battery  voltage and the polarity of the terminals. Polarity marking is not required if 
incorrect insertion of the battery  by the user  is unlikely to occur due to the construction of the 
appliance.  
If more than one battery type can be used with the appliance, the appliance shall be marked 
with the type reference of at least one of the battery types that can be used together with either 
the s ymbol ISO 7000 -0790  (2004- 01) or with the substance of the following:  
See instruction manual for additional battery  types . 
If appliances use more than one battery , appliances shall be marked to indicate correct polarity 
connection of the batteries . 
If rele vant, the positive terminal shall be indicated by symbol IEC  60417 -5005  (2002- 10) and 
the negative terminal by symbol IEC 60417- 5006  (2002- 10). 
Examples of acceptable marking of an appliance using three batteries  are shown in Figure B. 2. 
Detachable batteries and separable batteries  shall be marked with the: 
– name, trade mark or identification mark of the manufacturer or responsible vendor;  
– model or type reference;  
– IP number according to degree of protection against ingress of water, other than IPX0.  
Detachable batteries and separable batteries  that are disconnected from the appliance for 
charging the battery  shall be marked with symbol ISO 7000- 0790  (2004- 01). They shall also 
be marked with symbol IEC 60417- 6413  (2019- 05) and the model or type reference of the 
battery charger or with the substance of the following:  
Use only with <model or type reference> battery charger . 
If more than one battery charger can be used to charge a detachable battery  and separable 
battery that is disconnected from the appliance for charging, the battery  shall be marked with 
the type reference of at least one of the battery chargers that can be used together with either 
the symbol ISO 7000 -0790  (2004- 01) or with the substance of the following:  
See instruction manual for additional battery chargers . 
Batteries that are user replaceable,  other than general purpose  batteries,  shall be marked with 
the: 
– name, trade mark or identification mark of the manufacturer or responsible vendor;  
– model or type reference;  
– nominal voltage.  
NOTE  Examples of general purpose batteries are AAA, AA, C and D alkaline batteries and some lead- acid 
batteries .  
Compliance is checked by inspection.  IEC 60335- 1:2020 © IEC 2020 – 141 –         7.6  
  
[symbol IEC 60417- 5005  
(2002- 10)]  plus; positive polarity  
 [symbol IEC 60417- 5006  
(2002- 10)] minus; negative polarity  
  [symbol IEC 60417- 6413  
(2019- 05)] battery charger  
7.12  Instructions shall be provided with the appliance so that the appliance can be used safely.  
For appliances intended for use at altitudes exceeding 2  000 m, the maximum altitude of use 
shall be stated.  
If it is necessary to take precautions during user maintenance , appropriate details shall be 
given.  
The instructions shall stat e the substance of the following:  
This appliance is not intended for use by persons (including children) with reduced 
physical, sensory or mental capabilities, or lack of experience and knowledge, unless they have been given supervision or instruction concerning use of the appliance by a person responsible for their safety.  
Children should be supervised to ensure that they do not play with the appliance.  
The instructions for appliances incorporating batteries  that are intended to be removed for 
charging or are intended to be replaced by the user and that can be contained in the small parts 
cylinder in Figure 13 shall state the substance of the following:  
WARNING: Keep out of reach of children. Swallowing can lead to chemical burns, 
perforation of soft tissue, and death. Severe burns can occur within 2 h of ingestion. 
Seek medical attention immediately.  
For appliances intended for use with batteries that use metal -ion chemistries , the instructions 
shall state the normal temperature ra nge for charging the battery . 
The instructions for battery -operated appliances shall contain the following information, as 
applicable:  
– the battery type;  
– details regarding safe disposal of used batteries ; 
– how to deal with leaking batteries . 
The instructions  for battery -operated appliances shall contain the substance of the following: 
– do not expose the appliance or battery  to excessive temperatures;  
– be aware of the risk of terminals of the battery -operated appliance  or battery  being short -
circuited by metal objects.  
Instructions for battery -operated appliances containing non- rechargeable  batteries  shall 
state the substance of the following:  
This appliance contains non- rechargeable batteries, these batteries are not to be 
recharged.  
 – 142 – IEC 60335- 1:2020 ©  IEC 20 20        Instructions for battery -operated appliances  containing batteries that are non -user -
replaceable shall state the substance of the following:  
This appliance contains batteries that are only replaceable by skilled persons.  
Instructions for battery -operated appliances containing batteries  that are non -replaceable 
shall state the substance of the following:  
This appliance contains batteries that are non -replaceable. When the battery is at end 
of life, the appliance shall be properly disposed of.  
The instructions for battery -operated appli ances incorporating batteries  intended to be 
removed for charging or replaced by the user shall include, as applicable, the substance of the 
following:  
– rechargeable batteries are to be removed from the appliance before being charged;  
– different types of bat teries or new and used batteries are not to be mixed; 
– exhausted batteries are to be removed from the appliance and safely disposed of;  
– if the appliance is to be stored unused for a long period, the batteries should be removed;  
– do not use non -rechargeable batteries in place of rechargeable batteries;  
– do not use modified or damaged batteries.  
The instructions for battery -operated appliances  incorporating batteries  intended to be 
removed for charging or replaced by the user shall include, as applicable, the following information:  
– the battery type reference;  
– the orientation of the battery  with regard to polarity;  
– the method of replacing batteries  including maintaining correct polarity.  
The instructions for battery -operated appliances  incorporating batteries  that are intended to 
be removed prior to disposal of the appliance shall include details regarding their safe removal and disposal.  
The instructions for battery -operated appliances  that use detachable batteries  and 
separable batteries that are disconnected from the appliance for charging the battery shall 
include the model or type reference of the battery charger to be used along with the substa nce 
of the following:  
WARNING: Use only with <model or type reference> battery charger . 
If the symbol for battery  charger  is used, its meaning shall be explained.  
NOTE  Instructions can be marked on the appliance as long as they are visible in normal use.  
7.15  The marking specified for batteries intended to be replaced by the user shall be in or 
adjacent to the battery  compartment.  
The marking to indicate correct polarity connection of the batteries  specified for appliances 
using more than one general purpo se battery  (battery  not designed or sold for a specific 
purpose) shall be in or adjacent to the battery  compartment.  
The type reference of the battery charger  shall be placed next to symbol  
IEC 60417 -6413  (2019- 05). IEC 60335- 1:2020 © IEC 2020 – 143 –         8 Protection against access to live parts  
This clause is not applicable to the appliance functional part of a battery- operated appliance 
and its batteries , providing the battery circuits do not have an earth connection or mains 
connection.  
NOTE  1 T he requirements for parts requiring protection against simultaneous contact are specified in B.22.3 and 
B.22.4.  
NOTE  2 The term appliance functional part is illustrated in Figure B.1 . 
10 Power input and current  
10.1  This subclause is not applicable.  
10.2 This subclause is not applicable.  
11 Heating  
11.1 Battery- operated appliances , their surroundings, and batteries shall not attain 
excessive temperatures in normal use.  
Compliance is checked by determining the temperature rise of the various parts under the 
conditions specified in B.11.1, 11.2, 11.3, 11.7, and 11.8.  
11.4 This subclause is not applicable.  
11.5 This subclause is not applicable.  
11.6 This subclause is not ap plicable.  
B.11. 1 Battery -operated appliances are tested under the conditions of normal operation. 
For appliances operated with detachable batteries  or separable batteries  that are 
disconnected from the appliance for charging purposes , the appliance is operated until it no 
longer operates due to depletion of the battery . On the completion of the test, the depleted 
battery  is immediately replaced with another battery  that is  fully charged , the battery  being 
the model or type reference of the battery  provided or indicated in the instructions. The test is 
repeated until the appliance no longer operates due to depletion of the battery  or until the 
temperature rises have stabiliz ed to values not more than 5 K higher than the temperature rises 
measured at the same locations during the first test, whichever occurs first.  
For appliances incorporating integral batteries or separable batteries not disconnected from 
the appliance for ch arging purposes, and that cannot perform their intended function while the 
batteries  are being charged, the appliance is operated continuously until it cannot perform its 
intended function due to the depletion of the batteries . 
For appliances operated with  batteries  that are replaceable or non- rechargeable batteries , 
the  appliance is operated until the minimum capacity of the  battery  as specified in Table B. 1 
has been delivered or until steady conditions are established, whichever occurs first.  
19 Abnormal operation  
19.1 For battery -operated appliances, instead of the tests specified, compliance is  checked 
by the tests of 19.2, 19.4, 19.7, 19.9, 19.11, 19.12, 19.14, 19.15, B.19.1 to B.19.5.   – 144 – IEC 60335- 1:2020 ©  IEC 20 20        Detachable batteries and separable batteries  are also subjected to the test of B.19.6.  
For battery -operated appliances , the tests are carried out under normal operation . 
19.2 Appliances with heating elements are tested under the conditions specified in Clause  11 
but with restricted heat dissipation.  
NOTE  Controls that operate during the test of Clause  11 are allowed to oper ate. 
19.7 The battery -operated appliance  is switched on and operated under stalled conditions 
by: 
– locking the rotor of appliances for which the locked rotor torque is smaller than the full load 
torque;  
– locking moving parts of other appliances.  
If an appliance has more than one motor, the test is carried out for each motor separately.  
The test is conducted at both I sc (high) and I sc (low), if testing with the artificial source described 
in B.5. 3. 
The test is conducted : 
– until the test sample achieves a steady condition, including returning to room temperature; 
or 
– until at a time period of at least 3 h has elapsed.  
19.11 Electronic circuits  are checked by evaluation of the fault conditions specified in 
19.11.2 for all circuits or parts of circuits, unless they comply with the conditions specified in 
19.11.1.  
NOTE  1 In general, examination of the appliance and its circuit diagram will reveal the fault conditions which have 
to be simulated, so that testing can be limited to those cases that may be expected to give the most unfavourable 
results.  
Appliances having a device with an off position  obtained by electronic disconnection, or a 
device that can place the appliance in a stand- by mode, are subjected to the tests of 19.11.4.  
NOTE 2  For information on general guidance relating to the sequence of tests for the evaluation of electronic 
circuits , reference is made to informative Annex  Q. It is noted that in the parts 2 there may be additional or alternative 
abnormal operation tests specified; these are not shown in the flow chart. For correct application of this standard , 
the normative text takes precedence over the guidance given in informative Annex Q. 
If the safety of the appliance under any of the fault conditions depends on the operation of a 
miniature fuse -link complying with IEC 60127, the test of 19.12 is carried out. The appliance 
shall comply with the conditions specified in 19.13.  
If a co nductor of a printed circuit board becomes open -circuited, the appliance is considered to 
have withstood the particular test, provided that the base material of the printed circuit board withstands the test of normative  Annex  E. 
19.11.2  When any of the fault conditions are simulated, the duration of the test is until steady 
conditions are established.  
19.11.4  Appliances having a device with an off position  obtained by electronic disconnection, 
or a device that can be placed in the stand- by mode, are subj ected to the tests of 19.11.4.1 and 
19.11.4.2. The tests are carried out with the appliance supplied by a battery that is fully 
charged , the device being set in the off position  or in the stand -by mode.  IEC 60335- 1:2020 © IEC 2020 – 145 –         Appliances incorporating a protective electronic circuit  are subjected to the tests of 19.11.4.1  
and 19.11.4.2. The tests are carried out after the protective electronic circuit  has operated 
during the relevant tests of Clause  19 except 19.2 and 19.11.3.  
19.11.4.8 Battery operated appliances  are supplied with a battery  that is fully charged and 
operated under normal operation  for approximately 60 s, and then subjected to a 60 s 
interruption of the battery  current. When the battery  current is restored, the appliance shall:  
– continue to operate normally from the same operating cycle point reached before the battery 
supply was interrupted; or  
– not continue operating without requiring manual intervention to restart from the same 
operating cycle point reached before the battery  supply was interrupted; or  
– not continue operating without requiring manual intervention to restart from the part of the cycle selected by the user.  
19.13 During the tests, the appliance shall not emit flames, molte n metal, or poisonous or 
ignitable gas in hazardous amounts and temperature rises shall not exceed the values shown 
in Table 9. No explosion or ignition of the battery  shall occur during or after the test.  
Venting  of the cells  is permitted provided that they have not vented by any means other than 
through their vents.  
NOTE 1  Gas vented from cells is not considered to be poisonous or ignitable in hazardous amounts.  
After the tests, and when the appliance has cooled to approximately room temperature , 
compliance with B.22.3 and B.22.5 shall not be impaired and the appliance shall comply with 20.2 and Clause 29, if it can still be operated.  
Table 9 – Maximum abnormal temperature rise  
Part  Temperature rise  
K 
Wooden supports, walls, ceiling and floor of the test corner and wooden 
cabinets  a 150 
a For motor -operated appliances, these temperature rises are not determined.  
 
For appliances which are immersed in or filled with conducting liquid in normal use, the 
appliance is immersed in or filled with water for 24  h before the test of B.22.5 is carried out.  
The appliance shall not undergo a dangerous malfunction , and there shall be no failure of 
protective electronic circuits  if the appliance is still operable.  
Appliances tested with an electronic switch in the off position , or in the stand -by mode, shall : 
– not become operational; or 
– if they become operational, no t result in a dangerous malfunction during or after the tests 
of 19.11.4.  
NOTE 2  Unintended operation that can impair safety, can result from careless use of appliances, such as : 
– storage of small appliances while connected to the supply;  
– placing flammable material on working surfaces of heating appliances; or  
– placing objects in areas near motorized appliances that are not expected to start.  
In an appliance containing lids or doors that are controlled by one or more interlocks, one of the interlocks may be released provided that both of the following conditions are fulfilled:   – 146 – IEC 60335- 1:2020 ©  IEC 20 20        – the lid or door does not move automatically to an open position when the interlock is 
released;  
– the appliance will not restart after the cycle in which the interlock w as released.  
19.15 For battery -operated appliances incorporating a manual voltage selector switch 
intended to select battery  voltage, this switch is set to the lowest voltage position and the 
highest voltage is applied.  
B.19.1  The supply terminals of a battery- operated appliance  having an indication of polarity 
are connected to the battery terminals of the opposite polarity, unless such a connection by 
the user is unlikely to occur due to the construction of the appliance.  
B.19.2  For battery -operated appliances with provision for multiple batteries , one or more of 
the batteries  shall be reversed and the appliance shall be operat ed, if reversal by the user of 
battery polarity is allowed by the construction.  
B.19.3  For battery -operated appliances  with motor(s), t he terminals of each motor are short 
circuited one at a time, where the resistance of the short -circuit does not exceed 10 mΩ and  
with the appliance operating under the conditions of Clause 11. The test is conducted until 
steady conditions are achieved, including returning to room temperature or until a time period 
of at least 3  h has elapsed. 
B.19.4  Appliances incorporating batteries  that use metal -ion chemistries are tested as follows.  
The test is conducted with all the cells of the battery  fully charged  and, for batteries 
consisting of more  than one cell , one cell fully discharged on a detachable  battery or 
separable battery connected to the appliance or on an appliance containing an integral 
battery . 
The main discharge connections of the battery are shorted with a resistance not to exceed 
10 mΩ. The test is conducted until a non-self-resetting protection device operates or an 
intentionally weak part  becomes permanently open -circuited or until the test sample returns 
to room temperature. 
NOTE  The main discharge connections for separable  batteries  or detachable batteries  are the battery  terminals. 
For an integral battery, this is the output connection closest to the cells including their control circuitry.  
B.19.5  The battery -operated appliance  and a ny cords except supply cords, as appropriate, 
are tested with the battery  connected, under the following fault conditions applied one at a time:  
– any cord provided between the battery- operated appliance  and a separable battery shall 
be short -circuited at the point along its length likely to produce the most adverse effects;  
– for appliances having batteries  that are replaceable and that can be removed without the 
aid of a tool, and having terminals that can be short -circuited by a thin straight bar, the 
terminals of the battery  are short -circuited;  
– charging terminals of the battery- operated appliance that are simultaneously accessible 
with the test probe 13 of IEC  61032 are short circuited so as to produce the most 
unfavourable re sult. 
The battery -operated appliance  is switched on and no additional mechanical load is applied. 
The tests are conducted until the test sample achieves a steady condition, including  returning 
to room temperature or, until a time period of at least 3  h has  elapsed. The resistance of the 
short circuit shall not exceed 10 mΩ. 
B.19.6  Detachable batteries and separable batteries are tested under the following fault 
condition.  IEC 60335- 1:2020 © IEC 2020 – 147 –         Combinations of detachable battery  terminals and separable battery  terminals simultaneously 
accessible by applying the test probe 13 of IEC 61032 are short circuited so as to produce the 
most unfavourable result. The resistance of the short circuit shall not exceed 10 mΩ. 
20 Stability and mechanical hazards  
B.20.1  The enclosure of a battery -operated appliance  incorporating an integral battery  that 
uses metal -ion chemistry shall withstand the pressure generated when a cell  vents during 
failure.  
Compliance is checked by inspection after the tests of Clause 19 for batteries  with a capacity 
less than 0,2 Ah, and measurement in the case of a) or by the test of b).  
a) The total area of the unobstructed openings in the enclosure allowing gasses to pass shall 
be not less than the value specified in Table B. 2; or 
b) a volume of air of the amount specified in Table B. 3 shall be injected through a  
(2,85  ± 0,05) mm diameter orifice into the enclosure at an initial overpressure of 
2 070 kPa ± 10 %. Test fittings used for the test shall not increase the enclosu re volume by 
more than 3  ml. The overpressure within the enclosure shall drop below 70  kPa within 30  s 
without any unintended rupturing damage to the enclosure 
Table B. 2 – Total area of openings for metal -ion cells  
Capacity of the single metal -ion cell 
with the highest capacity  Min. total area of openings  
Ah mm2 
0,2 ≤ Ah < 5  20 
5 ≤ Ah < 25  30 
25 ≤ Ah < 100  50 
Ah ≥  100 100 
 
Table B. 3 – Volume of air injected at 2 070 kPa  
Capacity of the single metal -ion cell 
with the highest capacity  Volume of air (±10 %)  
Ah ml 
0,2 ≤ Ah < 5  20 
5 ≤ Ah < 25  30 
25 ≤ Ah < 100  50 
Ah ≥  100 100 
 
B.20.2  The enclosure of detachable batteries  and separable batteries  that use metal -ion 
chemistries shall withstand the pressure generated when a cell vents during failure.  
Compliance is checked by inspection after the tests of Clause 19 for batteries  with a capacity 
less than 0,2 Ah, and measurement in the case of a) or by the test of b).  
a) The total area of the unobstructed openings in the enclosure allowing gasses to pass shall be not less than the value specified in Table B. 2; or   – 148 – IEC 60335- 1:2020 ©  IEC 20 20        b) a volume of air of the amount specified in Table B. 3 shall be injected through a  
(2,85  ± 0,05) mm diameter orifice into the enclosure at an initial overpressure of 
2 070 kPa ± 10 %. Test fittings used for the test shall not increase the enclosure volume by 
more than 3  ml. The overpressure within the enclosure shall drop below 70  kPa within 30 s 
without any unintended rupturing damage to the enclosure . 
21 Mechanical strength  
21.1 Battery- operated appliances shall have adequate mechanical s trength and shall be 
constructed to withstand such rough handling that may be expected in normal use.  
Compliance is checked as follows.  
The appliance fitted with fully charged batteries and rigidly supported is subject to test Ehb 
of IEC 60068 -2-75. Three blows, each having an impact energy of 0,5  J, are applied to every 
point of the appliance enclosure that is likely to be weak.  
If necessary, the blows are also applied to handles, levers, knobs and similar parts and to signal 
lamps and their covers but only if the lamps or covers protrude from the enclosure by more than 
10 mm or if their surface area exceeds 4  cm2. Lamps within the appliance and their covers are 
only tested if they are likely to be damaged in normal use.  
When applying the release cone to the guard of a visibly glowing heating element , the 
hammer head passing through the guard shall not strike the heating element.  
If there is doubt as to whether a defect has occurred by the application of test Ehb of 
IEC 60068 -2-75, this defect is neglecte d and the group of three blows is applied to the same 
place on a new sample which shall then withstand the test.  
Hand- held battery -operated appliances shall also be subjected to test free- fall – procedure 
1, of IEC 60068-2- 31. They shall be dropped three t imes from a height of 1 m onto a concrete 
surface. The sample shall be positioned to vary the point of impact. Batteries  shall be fully 
charged  prior to the test. Hand- held battery- operated appliances  employing detachable 
batteries  are tested with and without the detachable battery. 
Following the above tests, the appliance shall not catch fire, leak fluid that is visible from the 
outside of the appliance enclosure or explode and shall meet the requirements of Clause 20, 
Clause 29 , B.22.3 and B.22.5 where short circuit of functional insulation  will impair 
compliance with this standard . 
Damage to the finish, small dents that do not reduce clearances or creepage distances below 
the values specified in Clause 29, and small chips that do not adversely affect protection against 
access to parts requiring protection against simultaneous contact according to B.22.3 are 
ignored.  
If a decorative cover is protected by an inner cover, fracture of the decorative cover is ignored 
if the inner cover itself withstands the test.  
Cracks not visible to the naked eye and surface cracks in fibre -reinforced mouldings and similar 
materials are ignored.  
B.21. 1 Separable batteries and detachable batteries , when not connected to the appliance, 
shall have adequate mechanical strength and shall be constructed to withstand such rough handling that may be expected in normal use.  
Compliance is checked as follows.  IEC 60335- 1:2020 © IEC 2020 – 149 –         The fully charged  battery , rigidly supported is subject to test Ehb of IEC  60068-2- 75. Three 
blows, each having an impact energy of 0,5  J, are applied to every point of the battery  
enclosure that is  likely to be weak.  
If there is doubt as to whether a defect has occurred by the application of test Ehb of 
IEC 60068 -2-75, this defect is neglected and the group of three blows is applied to the same 
place on a new sample which shall then withstand the test.  
Detachable batteries and separable batteries  shall also be subjected to the test free -fall – 
procedure 1, of IEC 60068 -2-31. They shall be dropped three times from a height of 1  m onto 
a concrete surface. The battery  shall be positioned to vary the point of impact. Batteries  shall 
be fully charged prior to the test.  
After the tests, visual inspection shall show there is no damage to the battery  and the battery 
shall not catch fire, leak fluid that is visible from the outside of the batte ry enclosure or explode 
and shall meet the requirements of Clause 20, Clause 29, B.22.4 and B.22.5 where short circuit 
of functional insulation will impair compliance with this standard. 
Damage to the finish, small dents that do not reduce clearances or creepage distances below 
the values specified in Clause 29, and small chips that do not adversely affect protection against 
access to parts requiring protection against simultaneous contact according to B.22.4 are 
ignored.  
If a decorative cover is protected by an inner cover, fracture of the decorative cover is ignored 
if the inner cover itself withstands the test.  
Cracks not visible to the naked eye and surface cracks in fibre -reinforced mouldings and similar 
materials are ignored.  
For batter ies that use metal -ion chemistry : 
– the open circuit voltage of the battery  24 h after the tests shall not be less than 90 % of the 
voltage measured immediately prior to the tests;  
– cells shall not have vented by any means other than through their vents.  
22 Construction  
22.11 Non-detachable parts that protect against electric shock , moisture or contact with 
moving parts shall be fixed in a reliable manner and withstand the mechanical stress occurring 
during normal use. Snap -in devices used for fixing such parts shall have an obvious locked 
position. The fixing properties of snap- in devices used in parts that are likely to be removed 
during installation or servicing shall be reliable.  
22.20 Direct contact between current carrying parts and thermal insulation that would impair 
compliance with this standard shall be effectively prevented unless such material is non -
corrosive, non -hygroscopic and non- combustible.  
The requirement is not applicable to glass -wool thermal insulation . 
NOTE  Non-impregnated slag -wool is an example of corrosive thermal insulation.  
22.24 This requirement does not apply to battery- operated appliances that do not contain 
parts requiring protection against simultaneous contact according to B.22.3 . 
22.25 This requirement does not apply to battery- operated appliances that do not contain 
parts requiring protection against simultaneous contact according to B.22.3 .  – 150 – IEC 60335- 1:2020 ©  IEC 20 20        22.26 This subclause is not applicable.  
22.27 This subclause is not applicable.  
22.28 This subclause is not applicable.  
22.29 This subclause is not applicable.  
22.30 This subclause is not applicable.  
22.31 This subclause is not applicable.  
22.32 This subclause is not applicable.  
22.33 Conductive liqui ds that are or may become accessible in normal use and conductive 
liquids that are in contact with accessible metal parts  shall not be in direct contact with current 
carrying parts or unearthed metal parts that are separated from current carrying parts  by basic 
insulation only or with other current carrying parts such that compliance with B.22.3 and B.22.4 
would be impaired.  
22.34 This subclause is not applicable.  
22.35 This subclause is not applicable.  
22.36 This subclause is not applicable.  
22.37 This subclause is not applicable.  
B.22.1  User accessible interfaces between elements of a battery system  (not mains 
connections) shall not employ appliance couplers according to IEC  60320  (all parts)  or 
IEC 60309 -2. 
User accessible interfaces between elem ents of a battery system  (not mains connections) 
shall not employ connectors of the following types unless the battery system  is adequately 
protected against the use of an incorrect supply : 
– barrel connectors with outside diameters of 6,5  mm or less;  
– concentric connectors with a diameter of 3,5 mm or less according to IEC 60603- 11. 
Compliance is checked by inspection, measurement and for determining adequacy of protection 
against use of an incorrect supply, by the following test.  
The mating connector shall be supplied by  a: 
– 5 V AC voltage that is increased in 5 V increments to 30 V for 5  min at each increment; and 
then ; 
– 10 V DC voltage with less than 10 % ripple in 10 V increments to 60 V for 5  min at each 
increment.  
The source shall be selected such th at its current capability does not limit the charging of the 
battery . 
During the application of incremental voltages, the appliance shall either be capable of 
operating normally or, if not, the appliance shall not emit flames, molten metal, or poisonous or  
ignitable gas in hazardous amounts and temperature rises shall not exceed the values shown in Table 9. No explosion or ignition of the battery shall occur during or after the test. Venting  IEC 60335- 1:2020 © IEC 2020 – 151 –         of the cells  is permitted provided that they have not vented by any means other than through 
their vents.  
B.22.2  The external surfaces of detachable batteries and separable batteries shall be 
protected against excessive heat from heat sources (directly or via heated discharge air) that 
would be present during operation of the appliance.  
Compliance is checked by inspection during the test of Clause 11. 
B.22.3  Battery -operated appliance s shall be so constructed and enclosed that there is 
adequate protection against simultaneous contact with two or more conductive parts  where  the: 
– voltage between them exceeds 42,4 V; and  
– current between the conductive parts  exceeds 2  mA for DC or 0,7 mA p eak for when ripple 
exceeds 10  %. 
Compliance is checked by inspection and the following test. 
Test probe B and test probe 18 of IEC 61032 are applied with a force not exceeding 1  N, the 
appliance being in every possible position except that appliances normally used on the floor 
and having a mass exceeding 40  kg are not tilted. The test probe is applied through openings 
to any depth that the probe will permit and is rotated or angled before, during and after insertion 
to any position. If the opening does not allow the entry of the probe, the force on the probe in 
the straight position is increased to 20  N when probe B is used or 10  N when probe 18 is used. 
If the probe then enters the opening, the test is repeated with the probe in the angled p osition.  
During the tests with test probe B, all detachable parts  are removed except lamps located 
behind a detachable cover are not removed. However, during insertion or removal of lamps 
which are located behind a detachable cover , protection against simultaneous contact with 
parts having a voltage between them exceeding 42,4  V shall be ensured.  
During the tests with test probe 18, the appliance shall be fully assembled as in normal use without any parts removed.  
However, test probe 18 is not applied to appliances for commercial use unless they are intended to be installed in an area open to the public.  
It shall not be possible to touch two or more conductive parts of opposite polarity with the probes 
if the voltage between them exceeds 42,4  V and the curre nt between them exceeds 2  mA for 
DC or 0,7  mA peak for when ripple exceeds 10  %. 
The current is measured using the circuit in Figure 4 of IEC 60990 :2016 . 
B.22.4  Separable batteries and detachable batteries shall be so constructed and enclosed 
that there is adequate protection against simultaneous contact with two or more conductive 
parts  where  the: 
– voltage between them exceeds 42,4 V; and  
– current between the conductive  parts exceeds 2  mA. 
Compliance is checked by inspection and the following test. 
Test probe B and test probe 18 of IEC 61032 are applied with a force not exceeding 1  N, the 
battery being in every possible position except that batteries having a mass exceeding 40 kg 
are not tilted. The test probe is applied through openings to any depth  that the probe will permit 
and is rotated or angled before, during and after insertion to any position. If the opening does 
not allow the entry of the probe, the force on the probe in the straight position is increased to  – 152 – IEC 60335- 1:2020 ©  IEC 20 20        20 N. If the probe then enters th e opening, the test is repeated with the probe in the angled 
position.  
During the tests with : 
– test probe B, all detachable parts  are removed;  
– test probe 18, no parts are removed.  
However, test probe 18 is not applied to batteries  for appliances for commercial use unless 
they are intended to be installed in an area open to the public.  
It shall not be possible to touch two or more conductive parts of opposite polarity with the probes 
if the voltage between them exceeds 42,4  V and the current between them exceeds 2 mA. 
The current is measured using the circuit in Figure 4 of IEC 60990 :2016 . 
B.22.5  Insulating materials providing protection against simultaneous contact with two or more 
conductive parts shall be adequate when : 
– they are within 1,0 mm of the conductive parts;  
– the voltage between the conductive parts exceeds 42,4 V peak; and 
– the current between the conductive  parts exceeds 2  mA for DC  or 0,7 mA peak for when 
ripple exceeds 10  %. 
Compliance is checked by inspection, measurement and the following  test. 
The insulating material is subjected for 60  s to 750 V or 1,2 times the working voltage  plus 
700 V, whichever is greater, in accordance with IEC 61180. The test voltage is applied on 
opposing sides of the insulating material.  
NOTE  This does not exclude the testing of the material as situated within the appliance.  
During the test care shall be taken to avoid overstressing parts not needed to provide protection against simultaneous contact with two or more conductive parts.  
The high -voltage source used for the test is to be capable of supplying a short circuit current I
s 
between the output terminals after the output voltage has been adjusted to the appropriate test voltage. The overload release of the circuit is not to be operated by any current below the tripping current I
r. The values of Is and Ir are 200 mA and 100 mA, respectively.  
No breakdown shall occur during the test.  
Glow discharges without a drop in voltage are neglected.  
The current is measured using the circuit in Figure 4 of IEC 60990 :2016. 
B.22.6  Vents of cells shall not be obstructed in such a way as to defeat their operation if 
venting  is relied upon for compliance with this standard.  
Compliance is checked by inspection and by the tests of this standard.  
23 Internal wiring  
23.3 Instead of the electric strength test of 16.3, battery -operated appliances  shall comply 
with B.22.3.  IEC 60335- 1:2020 © IEC 2020 – 153 –         23.5 For battery -operated appliances compliance is checked by the test of B.22.5.  
24 Components  
24.1 Batteries  are not required to co mply with IEC  62133-1 :2017  or IEC 62133-2 :2017 . They 
are tested as part of the appliance according to this standard.  
24.1.1 This subclause is not applicable.  
24.1.3 Switches in battery -operated appliances  shall have adequate breaking capacity and 
shall withstand, without excessive wear or other harmful effect, the mechanical, electrical, and 
thermal stresses occurring in the battery -operated appliance. 
The relevant standard for switches is IEC 61058-1-1 :2016 for mechanical switches and 
IEC 61058 -1-2:2016  for electronic switches. The number of cycles declared for 7.4 of 
IEC 61058 -1:2016  shall be at least 10  000 under the load conditions encountered in the 
appliance, this being the declared specific load according to 7.2.5 of IEC 61058-1 :2016 . If the 
switch makes and breaks a locked rotor current, the number of cycles declared for 7.4.9 of 
IEC 61058 -1:2016  shall b e at least 50 under the load conditions encountered in the appliance, 
this being the declared specific load according to 7.2.5 of IEC 61058-1 :2016 . 
The declared number of operating cycles is only applicable for switches required for compliance 
with this standard.  
Unless switches have been previously tested to and found to comply with IEC 61058 -1-1:2016 
or IEC 61058 -1-2:2016  for the number of cycles declared , compliance is checked by the 
following tests conducted on separate samples : 
– 50 cycles of making and breaking the locked motor current, if any, encountered in the 
battery -operated appliance  incorporating a battery that is fully charged. Each "on" period 
having a duration of not more than 0,5 s and each "off" period having a duration of at least 
10 s; 
– 10 000 cycles of making and breaking the current encountered in a battery -operated 
appliance  incorporating a battery that is fully charged  with no additional mechanical load. 
The switch is actuated at a uniform rate of 30 cycles per minute.  
The switch shall complete the required cycles of operation and shall have no electrical or 
mechanical failure. At the end of the tests : 
– the switch contacts shall op erate properly in the "on" and "off" positions;  
– the temperature rise of the switch terminals shall not have increased by more than 30 K 
above the temperature rise measured in Clause 11. 
B.24.1  The relevant standards  for non- acid based electrolyte  cells  employed in batteries  are 
IEC 62133 -1:2017  for nickel systems and IEC 62133-2 :2017 for lithium systems.  
NOTE  The requirement for cells does not extend to the battery  itself.  
A battery  that uses metal -ion chemistry  shall additionally be subjected to the tests of 
Subclauses 7.3.8.1 (vibration) and 7.3.8.2 (mechanical shock) of IEC 62133-2 :2017 . 
25 Supply connection and external flexible cords  
25.9 The requirement also applies to i nterconnection cords  of battery- operated appliances . 
25.14 The requirement also applies to i nterconnection cords  of battery -operated 
appliances .  – 154 – IEC 60335- 1:2020 ©  IEC 20 20        25.15 The requirement also applies to i nterconnection cords  of battery -operated 
appliances . 
B.25.1  Insulated conductors of interconnect ion cords  of battery -operated appliances shall 
comply with the requirements for internal wiring and shall be provided with at least 0,5 mm thick 
outer sheath made of insulating material equivalent to that of supply cords  described in 25.7.  
Compliance is ch ecked by inspection and by test.  
26 Terminals for external conductors  
B.26.1  Terminal devices in an appliance for the connection of the flexible leads or flexible cord 
connecting a separable battery  shall be so located or shielded that there is no risk of incorrect 
connection.  
Compliance is checked by inspection.  
27 Provision for e arthing  
27.1 The battery -operated appliance  shall have no provision for a protective earth but may 
incorporate a functional earth . 
29 Clearances, creepage distances and solid insulation  
29.1 Clearances shall not be less than the values specified in Table 16, taking into account 
the rated impulse voltage . For battery -operated appliances , the rated impulse voltage shall 
be 500  V for  working voltages less than 50  V and 1 500 V for all other  working voltages.   
However, if the construction, including between parts of opposite polarity for connecting the 
battery , is such that the distances could be affected by wear, by distortion, by movement of the 
parts or during assembly, the clearances for rated impulse voltages of 1 500 V are increased 
by 0,5  mm and the impulse voltage test is not applicable.  
NOTE  The procedure for assessing clearances is given in informative Annex  L. 
B.29.1.1  For parts requiring protection against simultaneous contact according to B.22.3 and 
B.22.4, the sum total of the clearances  between each of these parts and their nearest 
accessible surfa ce shall not be less than two times the Table 16 clearance  taking into account 
the rated impulse voltage . For the purpose of this determination, at least one of the 
clearances  shall be not less than 1,0 mm. 
Compliance is checked by measurement.  
NOTE  The procedure for assessing clearances is given in Clause L.3.  
B.29.2.1  For parts requiring protection against simultaneous contact according to B.22.3 and 
B.22.4, the sum total of the creepage distances between each of these parts and their nearest 
accessible surface shall not be less than two times the Table 17 creepage dist ances . For the 
purpose of this determination, at least one of the creepage distances  shall be not less than 
1,0 mm. 
Compliance is checked by measurement.  
NOTE  The procedure for assessing creepage distances  is given in Clause L.2.  IEC 60335- 1:2020 © IEC 2020 – 155 –         30 Resistance to heat and fire  
30.1 External parts of non- metallic material, the deterioration of which might cause the 
battery -operated appliance , separable battery or detachable battery to fail to comply with 
this annex, shall be sufficiently resistant to heat.  
a) 
 Complete appliance:  
Tested to main part of standard while operated or 
charged by mains or renewable energy source 
(otherwise not applicable)  
Tested to normative  Annex  B when operated on 
battery  power  
b) 
 Detachable power supply part:  
Tested to main part of standard with and without the 
appliance connected  
Complete appliance:  
Tested to main part of standard while operated by or charged by mains or renewable energy source 
Appliance functional part : 
Tested to normative  Annex  B when operated on 
battery  power  
c) 
  
Detachable power supply part:  
Tested to main part of standard with and without the 
appliance connected  
Complete appliance:  
Tested to main part of standard while operated by or charged by mains or renewable energy source 
Appliance functional part : 
Tested to normative  Annex  B when operated on 
battery  power  
d) 
  Detachable power supply part:  
Tested to main part of standard with and without the 
appliance connected  
Complete appliance:  
Tested to main part of standard while operated by or charged by mains or renewable energy source 
Appliance functional part : 
Tested to normative  Annex  B when operated on 
battery  power  
 
Figure B. 1 – Examples of battery- operated appliance constructions 
and application of normative  Annex  B (1 of 2)  
 
 – 156 – IEC 60335- 1:2020 ©  IEC 20 20        e) 
  
Battery charger:  
Tested to IEC 60335-2- 29 
Detachable battery:  
Tested to normative Annex  B 
Complete appliance:  
Tested to normative Annex  B when operated on 
battery  power with detachable battery  attached  
f) 
  
Detachable power supply part:  
Tested to main part of standard with and without the 
battery  connected  
Separable battery:  
Tested to normative Annex  B 
Complete appliance:  
Tested to main part of standard while operated by 
mains or renewable energy source while the battery  
is being charged: 
Appliance functional part : 
Tested to normative  Annex B when operated on 
battery  power with separable battery attached but 
detached from detachable power supply part : 
Key 
CA complete appliance  
A appliance functional part  
B battery  
S supply  
DB detachable battery   
CC charge circuitry  
PS detachable power supply part  
BC battery charger  
..... detachable connection  
---- non- detachable connection  
 
Figure B.1  (2 of 2)  
 
IEC 60335- 1:2020 © IEC 2020 – 157 –          
Figure B. 2 – Examples of correct polarity connection marking  
representing three batteries  
 – 158 – IEC 60335- 1:2020 ©  IEC 20 20        Annex  C 
(normative)  
 
Ageing test on motors 
This annex is applicable when there is doubt with regard to the temperature classification of the 
insulation of a motor winding, for example: 
– if the temperature rise of the motor winding exceeds the values specified in Table 3;  
– when well -known insulating materials are used in an unconventional way; 
– when combinations of  materials of different temperature classes are used at a temperature 
higher than that allowed for the lowest class;  
– when materials are used for which sufficient experience is not available, for instance in 
motors having integral core insulation.  
This test  is carried out on six samples of the motor.  
The rotor of each motor is locked and a current is passed individually through the rotor winding and the stator winding, this current being such that the temperature of the relevant winding is equal to the maxim um temperature rise measured during the test of Clause 11, increased by 
25 K. This temperature is further increased by one of the values chosen from Table C.1 . The 
corresponding total time during which the current is passed is indicated in the table.  
Table C. 1 – Test conditions  
Temperature increase  Total time  
K h 
0 ± 3 p a 
10 ± 3 0,5 p  
20 ± 3 0,25 p  
30 ± 3 0,125 p  
NOTE  The temperature increase chosen is selected by 
the manufacturer. 
a p is 8 000 unless otherwise specified in the relevant 
part 2.  
 
The total time is divided into four equal periods, each being followed by a period of 48  h during 
which the motor is subjected to the humidity test of 15.3. After the final humidity test, the insulation shall withstand the electric strength test of 16.3, but with the test volt age reduced to 
50 % of the value specifi ed. 
After each of the four periods and before the subsequent humidity test, the leakage current of the insulating system is measured as specified in 13.2, any component not forming part of the 
insulation system under test being disconnected before the measurement is made.  
The leakage current shall not exceed 0,5  mA. 
Failure of only one of the six motors during the first of the four periods of the test is ignored.  
If one of the six motors fails during the second, third or fourth period of the test, the remai ning 
five motors are subjected to a fifth period followed by the humidity test and the electric strength 
test. 
The remaining five motors shall complete the test.  IEC 60335- 1:2020 © IEC 2020 – 159 –         Annex  D 
(normative)  
 
Thermal motor protectors  
This annex is applicable to appliances having motors that incorporate thermal motor protectors 
that are necessary for compliance with this standard. 
The appliance is supplied at rated voltage  and is operated under stalled conditions by : 
– locking the rotor o f appliances for which the locked rotor torque is smaller than the full load 
torque;  
– locking moving parts of other appliances.  
The duration of the test is as follows:  
– motors having self -resetting thermal motor protectors are operated for 300 cycles or for 72 h, 
whichever occurs first, unless they are likely to be permanently subjected to the supply 
voltage, in which case the duration is 432 h; 
– motors having non- self-resetting thermal motor protectors are operated for 30 cycles, the 
thermal motor protector being reset as soon as possible after each operation, but in not less 
than 30 s. 
During the test, temperatures shall not exceed the values specified in 19.7 and the appliance 
shall comply with 19.13.  
  – 160 – IEC 60335- 1:2020 ©  IEC 20 20        Annex  E 
(normative)  
 
Needle -flame test  
The needle- flame test is carried out in accordance with IEC 60695 -11-5 :2016  with some of the 
clauses of IEC 60695- 11-5:2016 being modified as follows.  
7 Flame application times  
Replacement:  
The duration of application of the test flame is 30  s ± 1 s. 
9 Test procedure  
9.2 Position of test specimen 
Modification : 
The specimen is arranged so that the flame can be applied to a vertical or horizontal edge as 
shown in the examples of Figure 2. 
9.3 Application of needle -flame  
Modification:  
The first paragraph does not apply.  
Addition:  
If possible, the flame is applied at least 10 mm from a corner.  
9.4 Number of test specimens 
Replacement:  
The test is carried out on one specimen. If the specimen does not withstand the test, the test may be repeated on two additional sp ecimens, both of which shall then withstand the test.  
11 Evaluation of test results  
Addition:  
The duration of burning (tb) shall not exceed 30  s. However, for printed circuit boards, the 
duration of burning shall not exceed 15 s. 
 IEC 60335- 1:2020 © IEC 2020 – 161 –         Annex  F 
(normative)  
 
Capacitors 
Capacitors likely to be permanently subjected to the supply voltage, and used for radio 
interference suppression or for voltage dividing, shall comply with the following clauses of 
IEC 60384 -14:2013 including IEC 60384- 14:2013/AMD1:2016, being  modified as follows . 
1.5 Terms and definitions 
1.5.3 This subclause is applicable.  
Class X capacitors are tested according to subclass X2.  
1.5.4 This subclause is applicable.  
Class Y capacitors are tested according to subclass Y2.  
1.6 Marking 
Items a) and b) of this subclause are applicable.  
3.4 Approval testing 
3.4.3.2 Tests 
Table  3 is applicable as follows:  
– group 0:  Subclauses 4.1, 4.2.1 and 4.2.5;  
– group 1A:  Subclause 4.1.1;  
– group 2:  Subclause 4.12;  
– group 3:  Subclauses 4.13 and 4.14;  
– group 6:  Subclause 4.17;  
– group 7:  Subclause 4.18.  
4.1 Visual examination and check of dimensions 
This subclause is applicable.  
4.2 Electrical tests  
4.2.1 This subclause is applicable.  
4.2.5 This subclause is applicable.  
4.2.5.2 Only Table 11 is applicable. The values for test A apply; however, for capacitors in 
heating appliances , the values for test B or test C apply.  
4.12  Damp heat, steady state 
This subclause is applicable.  
Only insulation resistance and voltage proof are checked (see Table 15).   – 162 – IEC 60335- 1:2020 ©  IEC 20 20        4.13  Impulse voltage  
This subclause is applicable.  
4.14  Endurance  
Subclauses 4.14.1, 4.14.3, 4.14.4 and 4.14.7 are applicable.  
4.14.7 Only insulation resistance and voltage proof are checked (see Table 16) together with 
a visual examination to ensure that there is no visible damage.  
4.17  Passive flammability test  
This subclause is applicable.  
4.18  Active flammability test 
This subclause is applicable.  
 IEC 60335- 1:2020 © IEC 2020 – 163 –         Annex  G 
(normative)  
 
Safety isolating transformers  
The following modifications to this standard are applicable for safety iso lating transformers . 
The clause numbers in this Annex refer to the clause numbers in the main part of this standard 
that are modified.  
7 Marking and instructions  
7.1 Transformers for specific use shall be marked with the: 
– name, trademark or identification mark of the manufacturer or responsible vendor;  
– model or type reference.  
NOTE  The definition of transformers for specific use is given in IEC  61558 -1:2017. 
17 Overload protection of transformers and associated circuits  
Fail- safe transformers shall comply w ith Subclause 15.5 of IEC 61558-1 :2017 . 
NOTE  This test is carried out on three transformers.  
22 Construction  
Subclauses 19.1 and 19.1.2 of IEC 61558 -2-6:2009  are applicable.  
29 Clearances, creepage distances and solid insulation  
29.1, 29.2 and 29.3 The distances specified in Table  20, Table 21 and Table  22 of  
IEC 61558 -1:2017  apply.  
For insulated winding wires complying with Subclause 19.12.3 of IEC 61558 -1:2017 there are 
no requirements for clearances or creepage distances. In addition, for windings providing 
reinforced insulation, the distances specified in Table 20 and Table 21 of IEC 61558 -1:2017  
are not assessed. 
For safety isolating transformers  subjected to periodic voltages with a frequency exceeding 
30 kHz, the clearances , creepage distances  and solid insulation values specified in 
IEC 60664 -4:2005  are applicable, if these values are greater than the values specified in 
Table  20, Table  21 and Table  22 of IEC 61558-1 :2017 . 
  – 164 – IEC 60335- 1:2020 ©  IEC 20 20        Annex  H 
(normative)  
 
Switches  
Switches shall comply with the following clauses of IEC 61058-1 :2016 and IEC 61058-1-1 :2016 , 
as appropriate, being  modified as follows . 
The tests are carried out under the conditions occurring in the appliance.  
Before being tested, switches are operated 20 times without load.  
8 Marking and documentation 
Switches are not required to be marked. However, a switch that can be tested separately from 
the appliance shall be marked with the manufacturer's name  or trademark and the type 
reference.  
13 Mechanism 
NOTE  The tests can be carried out on a separate sample.  
15 Insulation resistance and dielectric strength  
Subclause 15.1 is not applicable.  
Subclause 15.2 is not applicable.  
Subclause 15.3 is applicable for  full disconnection and micro- disconnection.  This test is carried 
out immediately after the humidity test of Subclause 15.3 of IEC 60335- 1. 
17 Endurance  
Compliance is checked on three separate appliances or switches.  
For 17.5.4 of IEC 61058-1-1 :2016 , the n umber of cycles of actuation declared according to 7.4 
is 10  000 unless otherwise specified in Subclause 24.1.3  of IEC 60335-1.  
Switches intended for operation under no load and which can be operated only with the aid of a tool are not subjected to the tests. This applies also for such switches operated by hand that 
are interlocked so that they cannot be operated under load. However, switches without this interlock are subjected to the test of 17.5.4 of IEC 61058-1-1 :2016  for 10 0 cycles of operation.  
Subclauses 17.3 and 17.6.2 of IEC 61058-1-1 :2016  are not applicable. The ambient 
temperature during the test is that occurring in the appliance during the test of Clause 11  in 
IEC 60335 -1, as specified in footnote b of Table 3. 
At th e end of the tests, the temperature rise of the terminals shall not have increased by more 
than 30 K above the temperature rise measured in Clause 11 of IEC 60335- 1. IEC 60335- 1:2020 © IEC 2020 – 165 –         20 Clearances, creepage distances, solid insulation and coatings of rigid 
printed board as semblies 
Clause 20  of IEC 61058 -1:2016  is applicable to clearances  across full disconnection and micro-
disconnection. It is also applicable to creepage distances  for functional insulation , across 
full disconnection and micro- disconnection, as stated in Table 14 . 
  – 166 – IEC 60335- 1:2020 ©  IEC 20 20        Annex  I 
(normative)  
 
Motors having basic insulation that is inadequate 
for the rated voltage of the appliance  
The following modifications to this standard are applicable for motors having basic insulation  
that is inadequate for the rated voltage of the appliance.  
The clause numbers in this Annex refer to the clause numbers in the main part of this standard 
that are modified.  Clauses that are additional to the clauses in the main part of this standard 
are identified by adding the Annex letter with the numbering starting at 1.  
8 Protection against access to live parts  
8.1 Metal parts of the motor are considered to be bare live parts . 
11 Heating  
11.3 The temperature rise of the body of the motor is determined instead of the temperature 
rise of the windings.  
11.8 The temperature rise of the body of the motor, where it is in contact with insulating 
material, shall not exceed the values shown in Table 3 for the relevant insulating material.  
16 Leakage current and electric strength  
16.3 The insulation between live parts  of the motor and its other metal parts is not subjected 
to this test.  
19 Abnormal operation  
19.1 The tests of 19.7 to 19.9 are not carried out. 
Appliances are also subjected to the test of I.19.1 . 
I.19.1 The appliance is operated at rated voltage with eac h of the following fault conditions:  
– short circuit of the terminals of the motor, including any capacitor incorporated in the motor circuit;  
– short circuit of each diode of the rectifier;  
– open circuit of the supply to the motor;  
– open circuit of any parallel  resistor, the motor being in operation.  
Only one fault is simulated at a time, the tests being carried out consecutively.  The faults are 
simulated as shown in Figure I. 1. 
22 Construction  
I.22.1  For class I appliances  incorporating a motor supplied by a rectifier circuit, the DC  
circuit shall be insulated from accessible parts of the appliance by double insulation or 
reinforced insulation. IEC 60335- 1:2020 © IEC 2020 – 167 –         Compliance is checked by the tests specified for double insulation and reinforced insulation . 
  
a) Parallel circuit  b) Series circuit  
Key 
—  original connection  
– – - short- circuit  
≈  open circuit  
A  short- circuit of the terminals of the motor  
B  short- circuit of a diode  
C  open circuit of the supply to the motor  
D  open circuit of the parallel resistor  
Figure I. 1 – Simulation of faults  
 
 – 168 – IEC 60335- 1:2020 ©  IEC 20 20        Annex  J 
(normative)  
 
Coated printed circuit boards 
Protective coatings of printed circuit  boards shall comply with IEC 60664-3 :2016  with some of 
the clauses of IEC 60664 -3:2016  being modified as follows.  
5 Tests  
5.1 General  
When production samples are used, three samples of the printed circuit board are tested.  
5.7 Conditioning of the test specimens  
5.7.2 Cold conditioning  
The test is carried out at –25 °C. 
5.7.4 Rapid change of temperature 
Severity 1 is specified , the number of cycles is 5 . 
5.7.5.2 Additional conditioning with respect to electromigration 
The test duration is 10 days.  
5.9 Additional tests 
This subclause is not applicable.  
 IEC 60335- 1:2020 © IEC 2020 – 169 –         Annex  K 
(informative ) 
 
Overvoltage categories  
The following information on overvoltage categories is extracted from IEC 60664-1 :2007 . 
Overvoltage category is a numeral defining a transient overvoltage condition.  
Equipment of overvoltage category IV is for use at the origin of the installation.  
NOTE  1 Examples of such equipment are electricity meters and primary overcurrent protection equipment.  
Equipment of overvoltage category III is equipment in fixed installat ions and for cases where 
the reliability and the availability of the equipment is subject to special requirements.  
NOTE  2 Examples of such equipment are switches in the fixed installation and equipment for industrial use with 
permanent connection to the fixed installation. 
Equipment of overvoltage category II is energy consuming equipment to be supplied from the 
fixed installation.  
NOTE  3 Examples of such equipment are appliances, portable tools and other household and similar loads.  
If such equipment is su bjected to special requirements with regard to reliability and availability, 
overvoltage category III applies.  
Equipment of overvoltage category I is equipment for connection to circuits in which measures are taken to limit transient overvoltages to an app ropriately low level.  
  – 170 – IEC 60335- 1:2020 ©  IEC 20 20        Annex  L 
(informative)  
 
Guidance for the measurement of clearances  
and creepage distances 
L.1 When measuring clearances , the following applies.  
The rated voltage  and overvoltage category are determined (see informative  Annex  K). 
NOTE  1 In general, appliances are in overvoltage category II.  
The rated impulse voltage  is determined from Table 15.  
If pollution degree 3 is applicable, or if the appliance is class 0 or class 01, the clearances for 
basic insulation  and functional insulation  are measured and compared with the values 
specified in Table 16. For other cases, the impulse voltage test may be  carried out if the rigidity 
requirements of 29.1 are met, otherwise the values specified in Table 16 apply. However, for 
functional insulation  that is subjected to a steady -state voltage or recurring peak voltage with 
a frequency not exceeding 30  kHz, the  clearances are also obtained from Table F.7a  in 
IEC 60664 -1:2007  or if the frequency exceeds 30  kHz, Clause 4 in IEC 60664-4 :2005 . The 
larger of the values so obtained is applied if they exceed the values specified in Table 16.  
Clearances of supplementary  insulation  and reinforced insulation  are measured and 
compared with the values specified in Table 16.  
NOTE  2 Special considerations apply for clearances subjected to higher working voltages than rated voltage . 
For these requirements, refer to the text in 29.1.5.  
NOTE  3 The sequence for determining clearances is shown in Figure L. 1. 
 
Figure L. 1 – Sequence for the determination of clearances 
IEC 60335- 1:2020 © IEC 2020 – 171 –         L.2 When measuring creepage distances , the following applies.  
The working voltage , pollution degree and material group are determined.  
The creepage distances  of basic insulation and supplementary insulation  are measured 
and compared with the values specified in Table 17 or Table 2 in IEC 60664-4 :2005  as 
appropriate. A particular creepage distance is then compared with the corresponding 
clearance  of Table 16 and enlarged if necessary in order not to be less than the clearance. 
For pollution degree  1, the reduced clearance  based on the impulse voltage test can be used. 
However, the creepage distance  cannot be less than the values of Table 17.  
The creepage distances of functional insulation  are measured and compared with the values 
specified in Table 18 or , for periodic working voltages exceeding 30  kHz, Table  2 of 
IEC 60664 -4:2005 . 
The creepage distances  of reinforced insulation  are measured and compared with twice the 
values specified in Table 17.  
NOTE  The sequence for determining creepage distances  is shown in Figure L.2  
 
Figure L. 2 – Sequence for the determination of creepage distances  
L.3 When measuring the sum total of distanc es between parts requiring protection against 
simultaneous contact according to B.29.1.1  and accessible surfaces, the distance from each 
part to the accessible surface shall be added together to determine the sum total. See  
Figure L. 3. 
 – 172 – IEC 60335- 1:2020 ©  IEC 20 20         
Key 
Dimension a positive bare part distance to the external surface represented by foil  stretched across the openings  
Dimension b negative bare part distance to the external surface represented by foil stretched across the openings  
a + b sum total as specified in B.29.1.1. 
Figure L. 3 – Measurement of clearances  
 
IEC 60335- 1:2020 © IEC 2020 – 173 –         Annex  M 
(informative ) 
 
Pollution degree  
The following information on pollution degrees is extracted from IEC 60664 -1:2007 . 
• Pollution  
The microenvironment determines the effect of pollution on the insulation. The macro -
environment, however, has to be taken into account when considering the microe nvironment.  
Means may be provided to reduce pollution at the insulation under consideration by effective 
use of enclosures, encapsulation or hermetic sealing. Such means to reduce pollution may not be effective when the equipment is subjected to condensation or if , in normal use, it generates 
pollutants itself.  
Small clearances can be bridged completely by solid particles, dust and water and therefore 
minimum clearances  are specified where pollution may be present in the microenvironment.  
NOTE  1 Pollution will become conductive in the presence of humidity. Pollution caused by contaminated water, 
soot, metal or carbon dust is inherently conductive.  
NOTE  2 Conductive pollu tion by ionized gases and metallic depositions occur only in specific instances, for example 
in arc chambers of switchgear or controlgear and is not covered by IEC  60664-1 :2007. 
• Degrees of pollution in the microenvironment  
For the purpose of evaluating creepage distances, the following four degrees of pollution in 
the microenvironment are established:  
– pollution degree 1: no pollution or only dry, non -conductive pollution occurs. The pollution 
has no influence;  
– pollution degree 2: only non -conductive pollution occurs, except that occasionally a 
temporary conductivity caused by condensation is to be expected;  
– pollution degree 3: conductive pollution occurs or dry non- conductive pollution occurs that 
becomes conductive due to condensation that is to be expected ; 
– pollution degree 4: the pollution generates persistent conductivity caused by conductive 
dust or by rain or snow.  
NOTE  3 Pollution degree 4 is not applicable to appliances.  
  – 174 – IEC 60335- 1:2020 ©  IEC 20 20        Annex  N 
(normative)  
 
Proof tracking test  
The proof tracking test is carried out in acco rdance with IEC 60112:2003  including 
IEC 60112:2003/AMD1:2009 with some of the clauses  of IEC 60112:2003 including 
IEC 60112:2003/AMD1:2009 being modified as follows.  
7 Test apparatus  
7.3 Test solutions 
Test solution A is used.  
10 Determination of proof tracking index (PTI)  
10.1 Procedure  
Modification:  
The proof voltage is 100  V, 175  V, 250 V, 400 V or 600  V, as appropriate.  
The test is carried out on five specimens.  
In case of doubt, a material is considered to have a PTI of the sp ecified value if it withstands 
the test at a voltage equal to the proof voltage reduced by 25  V, the number of drops being 
increased to 100.  
10.2 Report  
Addition:  
The report shall state if the PTI value was based on a test using 100 drops with a test voltage 
of (PTI -25) V.  
 IEC 60335- 1:2020 © IEC 2020 – 175 –         Annex  O 
(informative)  
 
Selection and sequence of the tests of Clause 30  
For correct application of this standard, the normative text takes precedence over the guidance 
given in this annex and reliance should not to be placed on these figures . 
 
a ∆T is not taken into account if the tests of 19.4 and 19.5 are terminated by the operation of a non- self-resetting 
protective device requiring the use of a tool or removal of a cover to reset it.  
Figure O. 1 – Tests for resistance to heat  
 – 176 – IEC 60335- 1:2020 ©  IEC 20 20         
Figure O. 2 – Selection and sequence of tests for resistance 
to fire in hand -held appliances 
 
Figure O. 3 – Selection and sequence of tests for resistance 
to fire in attended appliances  
IEC 60335- 1:2020 © IEC 2020 – 177 –         
 
Figure O. 4 – Selection and sequence of tests for resistance 
to fire in unattended appliances  
 – 178 – IEC 60335- 1:2020 ©  IEC 20 20         
"Within a distance of 3 mm" means falling within the dotted boundary formed by the cylinder with hemispherical 
ends, as shown in the above drawing.  
Some examples:  
 
a) Example 1  
 
b) Example 2  
 
c) Example 3  
 
d) Example 4  
Key 
A connection zone 
B non- metallic material  
C non- metallic material  
D air gap  
I current greater than 0,5 A in attended appliances and greater than 0, 2  A in unattended appliances  
IEC 60335- 1:2020 © IEC 2020 – 179 –         X distance from the connection  
NOTE  The distance X  is not measured from the point of the connection since there is little or no temperature 
gradient across the current -carrying conductors.  
Explanation  
Example  X ≤ 3 mm  X > 3 mm  
Material subjected to glow -wire test  Material subjected to glow -wire test  
B C B C 
1 Yes Yes No Yes 
2 Yes Yes No Yes 
3 Yes Yes No Yes 
4 Yes Yes No Yes 
 
Consequential test  
In unattended appliances, B is also subjected to the needle -flame if C produces a flame that persists for longer than 
2 s during the glow -wire test of 30.2.3.2. 
Figure O. 5 – Some applications of the term "within a distance of  3 mm"  
  – 180 – IEC 60335- 1:2020 ©  IEC 20 20        Annex  P 
(informative)  
 
Guidance for the application of this standard to appliances  
used in  tropical  climates 
The following modifications to this standard are applicable for class 0 appliances and class 0I 
appliances  having a rated voltage  exceeding 150  V, that are intended to be used in countries 
having a  tropical  climate and that are marked with symbol IEC 60417- 6332 (2015 -06). 
NOTE  Tropical  climates are characterized by high humidity and high ambient temperatures with little variation, as 
specified in IEC 60721-2- 1. 
They may also be applied to class I appliances having a rated voltage  exceeding 150  V that 
are intended to be used in countries having a tropical climate and that are marked  with symbol 
IEC 60417 -6332 (2015- 06), if they are liable to be connected to a supply mains that excludes 
the protective earthing conductor due to deficiencies in the fixed wiring system.  
The clause numbers in this Annex refer to the clause numbers in the main part of this standard 
that are modified.  
5 General conditions for the tests  
5.7 The ambient temperature for the tests of Clauses 11 and 13 is 403
0+  °C. 
7 Marking and instructions  
7.1 The appliance shall be marked with symbol IEC 60417 -6332 (2015- 06). 
7.6 
 [symbol IEC 60417- 6332  
(2015- 06)] tropical climate  
7.12  The instructions shall state that the appliance is to be supplied through a residual current 
device (RCD) having a rated residual operating current not exceeding 30 mA. 
The instructions shall state the substance of the following:  
This appliance is considered to be suitable for use in countries  having a tropical  climate. 
It may also be used in other countries.  
If symbol IEC  60417- 6332 (2015 -06) is used, its meaning shall be explained.  
11 Heating  
11.8 The values of Table 3 are reduced by 15 K. 
13 Leakage current and electric strength at operating temperature  
13.2 The leakage current for class I appliances shall not exceed 0,5 mA. IEC 60335- 1:2020 © IEC 2020 – 181 –         15 Moisture resistance  
15.3 The value of t is 37 °C. 
16 Leakage current and electric strength  
16.2 The leakage current for class I appliances shall not exceed 0,5 mA. 
19 Abnormal operation  
19.13 The leakage current test of 16.2 is applied in addition to the electric strength test of  16.3.  
  – 182 – IEC 60335- 1:2020 ©  IEC 20 20        Annex  Q 
(informative)  
 
Sequence of tests for the evaluation of electronic circuits  
For correct application of this standard , the normative text takes precedence over the guidance 
given in this annex and reliance should not be placed on th e flow chart  of Figure Q. 1. IEC 60335- 1:2020 © IEC 2020 – 183 –         
 
Figure Q. 1 – Flowchart outlining the sequence of tests  
for the evaluation of electronic circuits (1 of 2)  
 – 184 – IEC 60335- 1:2020 ©  IEC 20 20        
 
Figure Q.1  (2 of 2)  
 
IEC 60335- 1:2020 © IEC 2020 – 185 –         Annex  R 
(normative)  
 
Software evaluation 
Programmable electronic circuits requiring software incorporating measures to control the 
fault/error conditions specified in Table R.1 or Table R.2 shall be validated in accordance with 
the requirements in this annex.  
NOTE  Tables R.1 and R.2 are based on Table H.1 of IEC  60730-1 :2013 including IEC  60730- 1:2013/AMD1 :2015 
that is, for the purpose of this annex, divided in two tables, Table R.1 for general fault/error conditions and Table R.2 
for specific fault/error conditions.  
R.1 Programmable electronic circuits using software  
Progra mmable electronic circuits requiring software incorporating measures to control the 
fault/error conditions specified in Table R. 1 or Table R. 2 shall be constructed so that the 
software does not impair compliance with the requirements of this standard.  
Compliance is checked by the inspections and tests, according to the requirements of this annex, 
and by examination of the documentation as required by this annex.  
R.2 Requirements for the architecture  
R.2.1  General  
R.2.1.1  Programmable electronic circuits  requiring software incorporating measures to 
control the fault/error conditions specified in Table R. 1 or Table R. 2 shall use measures to 
control and avoid software -related faults/errors in safety -related data and safety -related 
segments of the software. 
Compliance is checked by the inspections and tests in R.2.2 to R.3. 4 inclusive. 
R.2.1. 2 Programmable electronic circuits  requiring software incorporating measures to 
control the fault/error conditions specified in Table R. 2 shall have one of the following structures:  
– single channel with periodic self -test and monitoring (see IEC  60730 -1:2013 including 
IEC 60730 -1:2013/AMD 1:2015 , H.2.16.7 ); 
– dual channel (homogenous) with comparison (see IEC 60730 -1:2013 including 
IEC 60730 -1:2013/AMD 1:2015 , H.2.16.3 ); 
– dual channel (diverse) with comparison (see IEC 60730 -1:2013 including 
IEC 60730 -1:2013/AMD 1:2015 , H.2.16.2 ). 
NOTE 1  Comparison between dual channel structures can be performed by:  
• use of a comparator (see IEC  60730-1 :2013 including IEC  60730- 1:2013/AMD1 :2015 H.2.18.3), or  
• reciprocal comparison (see IEC  60730-1 :2013 including IEC  60730- 1:2013/AMD1 :2015 H.2.18.15).  
Programmable electronic circuits requiring software incorporating measures to control the 
fault/error conditions specified in Table R. 1 shall have one of the following structures:  
– single channel with functional test (see IEC  60730 -1:2013 including 
IEC 60730 -1:2013/AMD 1:2015  H.2.16.5 ); 
– single channel with periodic self -test (see IEC 60730 -1:2013 including 
IEC 60730 -1:2013/AMD 1:2015 , H.2.16.6 ); 
– dual channel without comparison (see IEC 60730-1 :2013 including 
IEC 60730 -1:2013/AMD 1:2015 , H.2.16.1 ).  – 186 – IEC 60335- 1:2020 ©  IEC 20 20        NOTE 2  Software structures incorporating measures to control the fault/error conditions specified in Table R.2  are 
also acceptable for programmable electronic circuits  with functions requiring software measures to control the 
fault/error conditions specified in Table R.1 . 
Compliance is checked by the inspections and tests of the software architecture in R.3.2.2 . 
R.2.2  Measures to control faults/errors  
R.2.2.1  When redundant memory with comparison is provided on two areas of the same 
component, the data in one area shall be stored in a different format from that in the other area 
(see software diversity, IEC 60730-1 :2013 including IEC 60730 -1:2013/AMD 1:2015 , H.2.18.19 ). 
Compliance is checked by inspection of the source code.  
R.2.2.2  Programmable electronic circuits  with functions requiring software incorporating 
measures to control the fault/error conditions specified in Table  R.2 and that use dual channel 
structures with comparison shall have additional fault/error detection means (such as periodic functional tests, periodic self tests, or independent monitoring) for any fault/errors not detected by the comparison.  
Compliance is checked by inspection of the source code.  
R.2.2.3  For programmable electronic circuits with functions requiring software incorporating 
measures to control the fault/error conditions specified in Table R.1  or Table R.2, means shall 
be provided for the recognition and control of  errors in transmissions to external safety -related 
data paths. Such means shall take into account errors in data, addressing, transmission timing and sequence of protocol.  
Compliance is checked by inspection of the source code.  
R.2.2.4  For programmable electronic circuits with functions requiring software incorporating 
measures to control the fault/error conditions specified in Table R.1 or Table R.2, the 
programmable electronic circuits  shall incorporate measures to address the fault/errors in 
safety -related segments and data indicated in Table R. 1 or Table R. 2 as appropriate.  
Compliance is checked by inspection of the source code.  IEC 60335- 1:2020 © IEC 2020 – 187 –         Table R. 1 – General fault/error conditions   
Component a Fault/error  Acceptable measures b, c 
 Definitions  
See 
IEC 60730- 1:2013 
including 
IEC 60730- 1:2013/  
AMD1:2015  
1  
Central 
processing unit 
(CPU)    
1.1    
Registers  Stuck at  Functional test, or  H.2.16.5  
  periodic self -test using either:  H.2.16.6  
  – static memory test, or  H.2.19.6  
  – word protection with single bit redundancy  H.2.19.8.2  
1.2 VOID     
1.3    
Functional test, or  H.2.16.5  
Programme  
counter  Stuck at  periodic self -test, or  H.2.16.6  
 independent time- slot monitoring, or  H.2.18.10.4  
  logical monitoring of the programme sequence H.2.18.10.2  
2    
Interrupt  
handling and execution  No interrupt  or 
too frequent  
interrupt  Functional test, or  H.2.16.5  
time- slot monitoring  H.2.18.10.4  
  
3    
Clock   Frequency monitoring, or  H.2.18.10.1  
  time slot monitoring  H.2.18.10.4  
 Wrong frequency  
(for quartz  
synchronized  
clock:  
harmonics/sub-harmonics  only)    
4  
Memory     
4.1    
Invariable 
memory  All single bit  
faults  Periodic modified checksum, or  H.2.19.3.1  
multiple checksum, or  H.2.19.3.2  
  word protection with single bit redundancy  H.2.19.8.2  
4.2    
Variable memory  DC fault  Periodic static memory test, or  H.2.19.6  
word protection with single bit redundancy  H.2.19.8.2  
4.3    
Addressing  
(relevant to variable and 
invariable memory)  Stuck at  Word protection with single bit redundancy  
including the address  H.2.19.8.2   – 188 – IEC 60335- 1:2020 ©  IEC 20 20        Component a Fault/error  Acceptable measures b, c 
 Definitions  
See 
IEC 60730- 1:2013 
including 
IEC 60730- 1:2013/  
AMD1:2015  
5    
Internal data 
path  Stuck at  Word protection with single bit redundancy  H.2.19.8.2  
5.1 VOID     
5.2 Addressing  Wrong address  Word protection with single bit redundancy 
including the address  H.2.19.8.2  
6    
External 
communication  
6.1 Data corruption of up to Hamming 
distance 3  Word protection with multi -bit redundancy, or  H.2.19.8.1  
Data  CRC – single word, or  H.2.19.4.1  
 transfer redundancy, or  H.2.18.2.2  
 protocol test  H.2.18.14  
6.2    
Addressing  Wrong address  Word protection with multi -bit redundancy 
including the address or  H.2.19.8.1  
  CRC – single word including the addresses, or  H.2.19.4.1  
  transfer redundancy, or  H.2.18.2.2  
  protocol test  H.2.18.14  
6.3    
Timing  Wrong point in time  Time -slot monitoring, or  H.2.18.10.4  
 scheduled transmission  H.2.18.18  
 Wrong sequence Logical monitoring, or  H.2.18.10.2  
 time- slot monitoring, or  H.2.18.10.4  
 scheduled transmission  H.2.18.18  
7    
Input/output periphery  Fault conditions specified in 19.11.2  Plausibility check  H.2.18.13  
7.1    
VOID  
7.2    
Analog I/O  
7.2.1     
A/D and D/A 
convertor  Fault conditions specified in 
19.11.2  Plausibility check  H.2.18.13  
7.2.2     
Analog 
multiplexer  Wrong addressing  Plausibility check  H.2.18.13  
8 VOID     
9    
Custom chips d 
e.g. ASIC, GAL, 
gate  array  Any output outside the  static 
and dynamic  
functional  
specification  Periodic self-test H.2.16.6  
 IEC 60335- 1:2020 © IEC 2020 – 189 –         NOTE  A Stuck -at fault model denotes a fault model representing an open circuit or a non- varying signal level. A 
DC fault model denotes a stuck -at fault model incorporating short circuits between signal lines.  
a For fault/error assessment, some components are divided into their sub- functions.  
b For each sub- function in the table, the Table R. 2 measure will cover the software fault/error. 
c Where more than one measure is given for a sub- function, these are alternatives. 
d To be divided as necessary by the manufacturer into sub- functions. 
 
Table R. 2 – Specific fault/error conditions  
Component a Fault/error  Acceptable measures b, c Definitions  
See 
IEC 60730- 1:2013 
including 
IEC 60730- 1:2013/A
MD1:2015  
1    
Central 
Processing Unit 
(CPU)    
1.1    
Registers  DC fault  Comparison of redundant CPUs by either:   
– reciprocal comparison  H.2.18.15  
– independent hardware comparator, or  H.2.18.3  
internal error detection, or  H.2.18.9  
redundant memory with comparison, or  H.2.19.5  
periodic self -tests using either   
– walkpat memory test  H.2.19.7  
– Abraham test  H.2.19.1  
– transparent GALPAT test; or  H.2.19.2.1  
word protection with multi -bit redundancy, or  H.2.19.8.1  
static memory test and  H.2.19.6  
word protection with single bit redundancy  H.2.19.8.2  
1.2    
Instruction 
decoding and 
execution  Wrong decoding 
and execution  Comparison of redundant CPUs by either:   
– reciprocal comparison  H.2.18.15  
– independent hardware comparator, or  H.2.18.3  
internal error detection, or  H.2.18.9  
periodic self -test using equivalence class test  H.2.18.5  
1.3    
Programme counter  DC fault  Periodic self -test and monitoring using either:  H.2.16.7  
– independent time- slot and logical monitoring  H.2.18.10.3  
– internal error detection, or  H.2.18.9  
comparison of redundant functional channels by either:   
– reciprocal comparison  H.2.18.15  
– independent hardware comparator  H.2.18.3   – 190 – IEC 60335- 1:2020 ©  IEC 20 20        Component a Fault/error  Acceptable measures b, c Definitions  
See 
IEC 60730- 1:2013 
including 
IEC 60730- 1:2013/A
MD1:2015  
1.4    
Addressing  DC fault  Comparison of redundant CPUs by either:   
– reciprocal comparison  H.2.18.15  
– independent hardware comparator; or  H.2.18.3  
internal error detection; or  H.2.18.9  
periodic self -test using  H.2.16.7  
– a testing pattern of the address lines; or  H.2.18.22  
– a full bus redundancy  H.2.18.1.1  
– a multi bus parity including the address  H.2.18.1.2  
1.5    
Data paths 
instruction  
decoding DC fault  and 
execution  Comparison of redundant CPUs by either:   
–  reciprocal comparison, or  H.2.18.15  
– independent hardware comparator, or  H.2.18.3  
– internal error detection, or  H.2.18.9  
– periodic self -test using a testing pattern, or  H.2.16.7  
–  data redundancy, or  H.2.18.2.1  
–  multi -bit bus parity  H.2.18.1.2  
2     
Interrupt handling and 
execution  No interrupt  or 
too frequent  
interrupt related 
to different sources  Comparison of redundant functional  channels by 
either   
–  reciprocal comparison,  H.2.18.15  
–  independent hardware comparator, or  H.2.18.3  
–  independent time- slot and logical monitoring  H.2.18.10.3  
3    
Clock  Wrong frequency  
(for quartz  
synchronized  
clock:  
harmonics/  
subharmonics  
only)  Frequency monitoring, or  H.2.18.10.1  
time- slot monitoring, or  H.2.18.10.4  
comparison of redundant functional channels   
by either:   
– reciprocal comparison  H.2.18.15  
– independent hardware comparator  H.2.18.3  
4. Memory     
4.1    
Invariable memory  99,6 % coverage 
of all information 
errors Comparison of redundant CPUs by either:   
– reciprocal comparison  H.2.18.15  
– independent hardware comparator, or  H.2.18.3  
redundant memory with comparison, or  H.2.19.5  
periodic cyclic redundancy check, either   
– single word  H.2.19.4.1  
– double word, or  H.2.19.4.2  
word protection with multi -bit redundancy  H.2.19.8.1  IEC 60335- 1:2020 © IEC 2020 – 191 –         Component a Fault/error  Acceptable measures b, c Definitions  
See 
IEC 60730- 1:2013 
including 
IEC 60730- 1:2013/A
MD1:2015  
4.2    
Variable memory  DC fault  and 
dynamic  cross 
links Comparison of redundant CPUs by either:   
– reciprocal comparison  H.2.18.15  
– independent hardware comparator, or  H.2.18.3  
redundant memory with comparison, or  H.2.19.5  
periodic self-tests  using either:  
– walkpat memory test  H.2.19.7  
– Abraham test  H.2.19.1  
– transparent GALPAT test, or  H.2.19.2.1  
word protection with multi -bit redundancy  H.2.19.8.1  
4.3    
Addressing  
(relevant to 
variable and invariable 
memory)  DC fault  Comparison of redundant CPUs by either:   
– reciprocal comparison, or  H.2.18.15  
– independent hardware comparator, or  H.2.18.3  
full bus redundancy  H.2.18.1.1  
testing pattern, or  H.2.18.22  
periodic cyclic redundancy check, either:   
– single word  H.2.19.4.1  
– double word, or  H.2.19.4.2  
word protection with multi -bit redundancy including 
the address  H.2.19.8.1  
5    
Internal data path     
5.1     
Data  DC fault  Comparison of redundant CPUs by either   
– reciprocal comparison  H.2.18.15  
– independent hardware comparator, or  H.2.18.3  
word protection with multi -bit redundancy  H.2.19.8.1  
including the address, or data redundancy, or  H.2.18.2.1  
testing pattern, or  H.2.18.22  
protocol test  H.2.18.14  
5.2     
Addressing  Wrong address 
and multiple 
addressing  Comparison of redundant CPUs by:   
– reciprocal comparison  H.2.18.15  
– independent hardware comparator, or  H.2.18.3  
word protection with multi -bit redundancy, including 
the address, or  H.2.19.8.1  
full bus redundancy; or  H.2.18.1.1  
testing pattern including the address  H.2.18.22   – 192 – IEC 60335- 1:2020 ©  IEC 20 20        Component a Fault/error  Acceptable measures b, c Definitions  
See 
IEC 60730- 1:2013 
including 
IEC 60730- 1:2013/A
MD1:2015  
6     
External 
communication    
6.1    
Data  Data corruption 
of up to 
Hamming distance 4  CRC – double word, or  H.2.19.4.2  
data redundancy or  H.2.18.2.1  
comparison of redundant functional channels by either   
– reciprocal comparison ; or H.2.18.15  
– independent hardware comparator  H.2.18.3  
6.2    
Addressing  Wrong address and multiple 
addressing  CRC – double word, including the address, or  H.2.19.4.2  
full bus redundancy of data and address, or  H.2.18.1.1  
comparison of redundant communication channels 
by either:   
– reciprocal comparison ; or H.2.18.15  
– independent hardware comparator  H.2.18.3  
6.3    
Timing  Wrong point in time  Time -slot and logical monitoring, or  H.2.18.10.3  
comparison of redundant communication channels by either:   
– reciprocal comparison; or  H.2.18.15  
– independent hardware comparator  H.2.18.3  
Wrong sequence Time-slot and logical monitoring, or  H.2.18.10.3  
comparison of redundant communication channels 
by either:   
– reciprocal comparison; or  H.2.18.15  
– independent hardware comparator  H.2.18.3  
7    
Input/output  
periphery  
7.1     
Digital I/O  Fault  conditions  
specified in 
19.11.2  Comparison of redundant CPUs by either:   
– reciprocal comparison  H.2.18.15  
– independent hardware comparator, or  H.2.18.3  
input comparison, or  H.2.18.8  
multiple parallel outputs, or  H.2.18.11  
output verification, or  H.2.18.12  
testing pattern, or  H.2.18.22  
code safety  H.2.18.2  IEC 60335- 1:2020 © IEC 2020 – 193 –         Component a Fault/error  Acceptable measures b, c Definitions  
See 
IEC 60730- 1:2013 
including 
IEC 60730- 1:2013/A
MD1:2015  
7.2     
Analog I/O  
7.2.1     
A/D- and D/A- 
convertor  Fault conditions  
in 19.11.2  Comparison of redundant CPUs by either:   
– reciprocal comparison  H.2.18.15  
– independent hardware comparator, or  H.2.18.3  
input comparison, or  H.2.18.8  
multiple parallel outputs, or  H.2.18.11  
output verification, or  H.2.18.12  
testing pattern  H.2.18.22  
7.2.2     
Analog 
multiplexer  Wrong addressing  Comparison of redundant CPUs by either:   
– reciprocal comparison  H.2.18.15  
– independent hardware comparator, or  H.2.18.3  
input comparison or  H.2.18.8  
testing pattern  H.2.18.22  
8    
Monitoring devices and 
comparators  Any output 
outside the static 
and dynamic 
functional specification  Tested monitoring, or  H.2.18.21  
redundant monitoring and comparison, or  H.2.18.17  
error recognizing means  H.2.18.6  
9    
Custom chips d 
e.g. ASIC, GAL, 
gate array  Any output outside the static 
and dynamic functional 
specification  Periodic self -test and monitoring, H.2.16.7  
dual channel (diverse) with comparison, or  H.2.16.2  
error recognizing means  H.2.18.6  
NOTE  A DC fault model denotes a stuck -at fault model incorporating short circuits between signal lines.  
a For fault/error assessment, some components are divided into their sub- functions.  
b For each sub- function in the table, the software measure will cover the Table R. 1 fault/error. 
c Where more than one measure is given for a sub- function, these are alternatives.  
d To be divided as necessary by the manufacturer into sub- functions. 
 
R.2.2.5  For programmable  electronic circuits with functions requiring software incorporating 
measures to control the fault/error conditions specified in Table R. 1 or Table R. 2, detection of 
a fault/error shall occur before compliance with Clause 19 is impaired. 
For appliances intended for remote communication  through public  networks , where 
normative Annex  U is applicable as determined by 22.62, detection of a fault/error shall occur 
before compliance with normative  Annex  U is impaired. 
Compliance is checked by inspection and testing of the source code.  
NOT E The loss of dual channel capability is deemed to be an error in a programmable electronic circuit  using a 
dual channel structure required for  software to control the fault/error conditions specified in Table R.2 .  – 194 – IEC 60335- 1:2020 ©  IEC 20 20        R.2.2.6  The software shall be referenced to relevant parts of the operating sequence and the 
associated hardware functions.  
Compliance is checked by inspection of the source code.  
R.2.2.7  Where labels are used f or memory locations, these labels shall be unique.  
Compliance is checked by inspection of the source code.  
R.2.2.8  The software shall be protected from user alteration of safety -related segments and 
data.  
Compliance is checked by inspection of the source c ode.  
R.2.2.9  The software and safety -related hardware under its control shall be initialized and 
shall terminate before compliance with Clause 19  is impaired . In addition, f or appliances 
intended for remote communication  through public networks  where normative Annex  U is 
applicable as determined by 22.62, the software and safety- related hardware under its control 
shall be initialized and shall terminate before compliance with normative  Annex  U is impaired.  
Compliance is checked by testing of the source code.  
R.3 Measures to avoid errors  
R.3.1  General  
For programmable electronic circuits with functions requiring software incorporating 
measures to control the fault/error conditions specified in Table R. 1 or Table R. 2, the following 
measures to avoid systematic faults in the software shall be applied.  
Software that incorporates measures used to control the fault/error conditions specified in  
Table R. 2 is inherently acceptable for software required to control the fault/error conditions 
specified in Table R. 1. 
NOTE  The content of these requirements is extracted from IEC 61508-3 :2010 and adapted to the needs of this 
standard.  
R.3.2  Specification  
R.3.2.1  Software safety requirements 
The specification of the software safety requirements shall include:  
– a description of each safety related function to be implemented, including its response 
time(s) ; 
• functions related to the application including their related software faults required to be controlled;  
• functions related to the detection, annunciati on and management of software or 
hardware faults . 
– a description of interfaces between software and hardware;  
– a description of interfaces between any safety and non -safety related functions;  
– a description of any compiler used to generate the object code from the source code, including details of any compiler switch settings used such as library function options, memory model, optimization, SRAM details, clock rate and chip details;  
– a description of any linker used to link the object code to executable lib rary routines.  IEC 60335- 1:2020 © IEC 2020 – 195 –         Compliance is checked by inspection of the documentation and as specified in R.3.2.2.2 . 
NOTE  Examples of some techniques/measures to meet these requirements can be found in Table R. 3. 
Table R. 3 – Semi -formal methods 
Technique / Measure  Informative references  
Semi -formal methods   
Logical/functional block diagrams   
Sequence diagrams   
Finite state machines/state transition diagrams  IEC 61508-7 :2010, B.2.3.2  
Decision/truth tables  IEC 61508-7 :2010, C.6.1  
 
R.3.2.2  Software architecture  
R.3.2.2.1  The specification of the software architecture shall include the following aspects:  
– techniques and measures to control software faults/errors (refer to R.2.2);  
– interactions between hardware and software;  
– partitioning into modules and their allocation to the specified safety functions;  
– hierarchy and call structure of the modules (control flow);  
– interrupt handling;  
– data flow  and restrictions on data access;  
– architecture and storage of data;  
– time-based dependencies of sequences and data.  
Compliance is checked by inspection of the documentation and as specified in R.3.2.2.2 . 
NOTE  Examples of some techniques/measures to meet these requirements can be found in Table R. 4. 
Table R. 4 – Software architecture specification  
Technique / Measure  Informative references  
Fault detection and diagnosis  IEC 61508-7 :2010, C.3.1  
Semi -formal methods:   
• Logic/function block diagrams   
• Sequence diagrams   
• Finite state machines / state transition diagrams  IEC 61508-7 :2010, B.2.3.2  
• Data flow diagrams  IEC 61508-7 :2010, C.2.2  
 
R.3.2.2.2  The architecture specification shall be validated against the specification of the 
software safety requirements by static analysis.  
NOTE  Example methods for static analysis are: 
• control flow analysis; ( IEC 61508-7 :2010, C.5.9);  
• data flow analysis; ( IEC 61508 -7:2010, C.5.10); 
• walk -through (software) ( IEC 61508-7 :2010, C.5.15);  
• design review ( IEC 61508-7 :2010, C.5.16).   – 196 – IEC 60335- 1:2020 ©  IEC 20 20        R.3.2.3  Module design and coding  
R.3.2.3.1  Based on the architecture design, software shall be suitably refined into modules. 
Software module design and coding shall be implemented in a way that is traceable to the 
software architecture and requirements.  
The module design shall specify:  
– function(s);  
– interfaces to other modules;  
– data.  
Compliance is checked by R.3.2.3.3  and by inspection of the documentation.  
NOTE  1 The use of computer aided design tools is accepted. 
NOTE  2 Defensive programming ( IEC 61508 -7:2010 , Subclause C.2.5) is recommended (e.g. range checks, check 
for division by 0, plausibility checks).  
NOTE  3 Examples of some techniques/measures to meet these requirements can be found in Table R.5 . 
Table R. 5 – Module design specification 
Technique / Measure  Informative references  
Limited size of software modules  IEC 61508-7 :2010, C.2.9  
Information hiding / encapsulation  IEC 61508-7 :2010, C.2.8  
One entry / one exit point in subroutines and functions  IEC 61508-7 :2010, C.2.9  
Fully defined interface  IEC 61508-7 :2010, C.2.9  
Semi -formal methods:   
• Logic/function block diagrams   
• Sequence diagrams   
• Finite state machines / state transition diagrams  IEC 61508-7 :2010, B.2.3.2  
• Data flow diagrams  IEC 61508-7 :2010, C.2.2  
 
R.3.2.3.2  Software code shall be structured.  
Compliance is checked by R.3.2.3.3  and by inspection of the documentation.  
NOTE 1  Structural complexity can be minimized by applying the following principles:  
• keep the number of possible paths through a software module small, and the relation between the input and 
output parameters as simple as possible;  
• avoid complicated branching and, in particular, avoid unconditional jumps (GOTO) in higher level languages;  
• where poss ible, relate loop constraints and branching to input parameters;  
• avoid using complex calculations as the basis of branching and loop decisions.  
NOTE 2  Examples of some techniques/measures to meet these requirements can be found in Tabl e R.6. IEC 60335- 1:2020 © IEC 2020 – 197 –         Table R. 6 – Design and coding standards  
Technique / Measure  Informative references  
Use of coding standard (see NOTE)  IEC 61508-7 :2010, C.2.6.2  
No use of dynamic objects and variables (see NOTE)  IEC 61508-7 :2010, C.2.6.3  
Limited use of interrupts  IEC 61508-7 :2010, C.2.6.5  
Limited use of pointers  IEC 61508-7 :2010, C.2.6.6  
Limited use of recursion  IEC 61508-7 :2010, C.2.6.7  
No unconditional jumps in programs in higher level 
languages IEC 61508-7 :2010, C.2.6.2  
NOTE  Dynamic objects and/or variables are allowed if a compiler is used which ensures that sufficient memory 
for all dynamic objects and/or variables will be allocated before runtime, or which inserts runtime checks for the 
correct online allocation of memory.  
 
R.3.2.3.3  Coded software shall be validated against the module specification by static analysis. 
The module specification shall be validated against the architecture specification by static 
analysis. 
R.3.3  Software validation  
The software shall be validated with reference to the requirements of the software safety 
requirements specification.  
NOTE  1 Validation is confirmation by examination and provision of objective evidence that the particular 
requirements for a specific intended use are fulfilled. Therefore, for example, software validation means confirming 
by examination and provision of objective evidence that the software satisfies the software safety requirement s 
specification.  
Compliance is checked by simulation of : 
– input signals present during normal operation; 
– anticipated occurrences ; 
– undesired conditions requiring system action.  
Test cases, test data and test results shall be reported.  
NOTE  2 Examples of some  techniques/measures to meet these requirements can be found in Table R.7 . 
Table R. 7 – Software safety validation  
Technique / Measure  Informative references  
Functional and black -box testing:  IEC 61508-7 :2010, B.5.1, B.5.2 
• Boundary value analysis  IEC 61508-7 :2010, C.5.4  
• Process simulation  IEC 61508-7 :2010, C.5.18  
Simulation, modelling:   
• Finite state machines  IEC 61508-7 :2010, B.2.3.2  
• Performance modelling  IEC 61508-7 :2010, C.5.20  
 
R.3.4  Management items 
R.3.4.1  Management of software versions  
A software version management system at the module level shall be put in place. All versions 
shall be  uniquely identified for traceability.   – 198 – IEC 60335- 1:2020 ©  IEC 20 20        NOTE  The use of a version ID number, if unique, is one possible solution.  
Compliance is checked by inspection of the documentation.  
R.3.4.2  Software modification  
R.3.4.2.1  Software modifications shall be based on a modification request which details the 
following:  
– the hazards which may be affected;  
– the proposed change;  
– the reasons for change.  
R.3.4.2.2  An analysis shall be carried out to determine the impact of the proposed modification 
on functional safety.  
R.3.4.2.3  A detailed specification for the modification shall be generated including the 
necessary activities for verification and validation, such as a definition of suitable test cases.  
R.3.4.2.4  The modification shall be carried out as planned.  
R.3.4.2.5  The assessment of t he modification shall be carried out based on the specified 
verification and validation activities. This may include:  
– a reverification of changed software modules;  
– a reverification of affected software modules;  
– a revalidation of the complete system . 
R.3.4. 2.6 All details of modification activities shall be documented.  
Compliance of the requirements in R.3.4.2.1  to R.3.4.2.6  is checked by inspection of the 
documentation.  
 IEC 60335- 1:2020 © IEC 2020 – 199 –         Annex  S 
(informative)  
 
Guidance for the application of this standard on measurement of power 
input and current based o n the requirements of 10.1 and 10.2 concerning 
the representative period  
For correct application of this standard, the normative text takes precedence over the guidance 
given in this annex and reliance should not to be placed on th e flow chart  of Figure S. 1. 
 
Figure S. 1 – Flowchart giving guidance on measurement of power input  
and current concerning the representative period 
 
 – 200 – IEC 60335- 1:2020 ©  IEC 20 20        Annex  T 
(normative)  
 
UV-C radiation effect on non -metallic materials  
This annex  provides requirements for non- metallic materials subject to direct or reflected UV -C 
radiation (100 nm to 280  nm) exposure and whose mechanical and electrical properties are 
relied upon for compliance with this standard. This annex does not apply to glass, ceramic and 
similar materials.  
NOTE  General -purpose incandescent and fluorescent lamps with ordinary glass envelopes are not considered to 
emit sig nificant UV -C radiation.  
The UV -C radiation effect on non -metallic materials is determined by measuring selected non -
metallic material properties before and after UV -C radiation conditioning. The conditioning and 
tests are carried out on non- metallic material specimens prepared according to the relevant 
standard for the test method. The standards and compliance criteria for parts providing 
mechanical support or impact resistance are specified in Table T. 1. The standard and 
compliance criteria for electrical insulation of internal wiring are specified in Table T. 2. 
The conditionin g apparatus and test procedure are as specified in ISO 4892 -1 and ISO 4892 -2, 
with some of their clauses being as modified follows . 
Modifications to  the clauses of  ISO 4892-1 :2016 . 
5.1 Irradiance 
5.1.1 The UV -C emitter shall be a low pressure mercury lamp with a quartz envelope having 
a continuous spectral irradiance of 10  W/m2 at 254 nm. 
NOTE  The quartz envelope blocks the 185 nm resonant wavelength for mercury that can generate ozone. 
5.2 Temperature 
5.2.5 The black -panel temperature shall be 63 °C ± 3 °C. 
5.3 Humidity and wetting  
5.3.1 Humidification of the chamber air is specified in part 2 when necessary.  
9 Test report 
This clause is not applicable.  
Modifications to the clauses of  ISO 4892-2 :2013 . 
7 Procedure  
7.1 General  
At least three test specimens of each non- metallic material providing mechanical support or 
impact resistance shall be exposed in each run to allow statistical evaluation of the results.  
Ten samples of the insulated internal wiring shall be exposed in each run. When the internal wiring is provided in more than one colour, the colour having the heaviest organic pigment 
loading is used.  IEC 60335- 1:2020 © IEC 2020 – 201 –         In determining the samples for testing, consideration should be given to samples coloured red 
or yellow which are known to have particular critical effects.  
7.2 Mounting the test specimens  
The specimens shall be attached to the specimen holders such that they are not subject to any 
applied stress.  
7.3 Exposure 
Before placing the specimens in the test chamber, the apparatus shall be operating under the 
specified exposure conditions. It shall be programmed to operate continuously and the 
conditions shall be maintained throughout the exposure, keeping any interruptions to service the apparatus and to inspect the specimens to a minimum.  
The test specimens and, if used, the irradiance- measuring instrument are exposed for 1  000 h. 
NOTE  Repositioning of the specimens during exposure is desirable and might be necessary.  
If it is necessary to remove a test specimen for periodic inspection, car e should be taken to 
avoid touching the exposed surface or altering it in any way.  
7.4 Measurement of radiant exposure  
If used, a radiometer shall be mounted and calibrated such that it measures the irradiance at the exposed surface of the test specimen.  
7.5 Determination of changes in properties after exposure  
The non -metallic material properties and test methods for parts providing mechanical support 
or impact resistance are specified in Table T. 1. 
Table T. 1 – Minimum property retention limits after UV -C exposure 
Parts to be tested  Property  Standard for the test 
method Minimum retention after 
test d 
Parts providing  
mechanical support  Tensile strength a or  ISO 527 (all parts)  70 %  
Flexural strength a,b  ISO 178 70 %  
Parts providing impact 
resistance  Charpy impact c or  ISO 179-1 70 %  
Izod impact c or  ISO 180 70 %  
Tensile impact c  ISO 8256  70 %  
a Tensile strength and flexural strength tests are to be conducted on specimens no thicker than the actual 
thicknesses . 
b The side of the sample exposed to UV -C radiation is to be in contact with the two loading points when using 
the three point loading method . 
c Tests conducted on 3,0 mm thick specimens for Izod impact and tensile impact tests and 4,0 mm thick 
specimens for Charpy impact tests are considered representative of other thicknesses, down to 0,8 mm. 
d Test specimens shall also show no visible signs of deterioration, such as crazing or cracking.  
 
The non- metallic material properties and test method for electrical insulation of internal wiring 
are specified in Table T. 2.   – 202 – IEC 60335- 1:2020 ©  IEC 20 20        Table T. 2 – Minimum electric strength for internal wiring after UV -C exposure 
Parts to be tested  Property  Standard for the test 
method Compliance  
Electrical insulation of 
internal wiring  Electric strength IEC 60335- 1 Subclause 
23.5  No breakdown shall occur during the test.  
 
8 Exposure report  
This clause is not applicable.  
 IEC 60335- 1:2020 © IEC 2020 – 203 –         Annex  U 
(normative)  
 
Appliances intended for remote communication through public n etworks  
The measures  given  in this annex  are intended  to avoid  unauthorized access and the effects 
of transmission failures via remote communication through public networks , where 
compliance with this standard could be impaired.  
However,  in general,  it does  not cover  aspects  concerning  confidentiality  of data and consumer  
privacy.  
U.1 Terms and definitions  
U.1.1  Definitions relating to remote  functionality  
U.1.1.1 
authentication  
provision for confirming that the entity sending or receiving a message is what or who it claims 
to be  
U.1.1.2 
authorization  
means to ensure that the authenticated entity requesting access to information, functions or 
services has the required authority  
U.1.1.3 
cryptographic  technique  
calculation of output data using a mathematical algorithm to encode input data with a key as a 
parameter  
U.1.1.4 
data integrity protection 
protection that enables the appliance to confirm the data has not been altered, lost or destroyed 
U.2 Marking and  instructions  
U.2.1 If there is provision for software download, instructions shall be provided on how or 
where  to obtain the unique name  or code  given  by the manufacturer,  that identifies  the current 
version of the software running in the  appliance.  The instructions shall also include the 
necessary steps the user must follow for the software update procedure.  
Compliance is checked by inspection.  
U.3 Construction  
U.3.1 Software enabling communication with a public network shall be partitioned into 
modules separate from software which is necessary to comply with the other requirements of 
this standard.  
Compliance is checked by inspection.  
U.3.2 Remote communication  shall be established, implemented and terminated by the 
appliance via software that provides  – 204 – IEC 60335- 1:2020 ©  IEC 20 20        – data integrity protection  concerning: 
• data corruption;  
• address corruption;  
• wrong timing or sequence;  
• permanent "auto -sending " or repetition;  
• interruption of data transfer; 
– means to detect and respond to  communication in which, for any reason, a message  being 
communicated is incomplete,  truncated, contains  errors  or has the correct  format  but 
delivers  information that is outside the range  expected for that type of message ; and  
– measures  to control  the fault/error conditions specified in Table R. 1. 
Compliance is checked by the inspections and tests of the software architecture in R.3.2.2 and 
evaluating the software in accordance with R.3.3.  
U.3.3 Measur es shall be provided to protect against hazards arising from the reception of 
messages  from several sources simultaneously or sequentially.  
Compliance is checked by evaluation according to U.3.2. 
U.3.4 Remote communication  shall not be enabled prior to authorization . Authorization 
shall be based on authentication . The authentication  process shall use cryptographic 
techniques  to ensure the identity of both parties.  
For the purposes of this requirement, communication between two entities  for preparation of 
the authentication  and authorization process is not considered remote communication . 
Compliance is checked by inspection  of the software. 
U.3.5 Measures shall be taken to prevent unauthorized access and to detect transmission 
faults/errors in the remote communication. 
NOTE  Examples of acceptable hardware- software measures are provided in Table U.1 . 
Compliance is checked by evaluation accor ding to U.3.2. 
 
  IEC 60335 -1:2020 © IEC 2020  – 205 –  Table U. 1 – Examples of acceptable measures against unauthorised access and transmission fault/error modes 
Measures 
To 
cover  Threats  Sequence 
numbera Time 
stampb Timeoutc Feedback 
messaged Source and destination 
identifiere Identification 
proceduref Safety codeg Cryptographic techniques  Transmission failure modes  h Repetition of a 
message X X       
Deletion of 
message X        
Insertion of 
message X   X X X   
Re-sequence 
message X X       
Corrupted, 
deleted or 
inserted data in a 
message       X i X 
Delay in sending/  
receiving the 
message   X X      Unauthorized 
access  
Masquerade j    X  X  X 
 NOTE 1  Examples of acceptable measures against unauthorized access can also be found in IEC 62280.  
a Additional data field containing a number that changes in a predefined way from message  to message.  
b Information concerning time of transmission attached to a message by the sender.  
c Delay between two messages exceeding a predefined allowed maximum time. If this is the case, an error can be assumed.  
d Response from a receiver to a sender, via a return channel.  
e Identifier which is assigned to each entity . This identifier can be a name, number or arbitrary bit pattern. This identifier will be used for the safety -related communication. 
Usually the identifier is added to the user data. 
f Procedure that enables entities to confirm the identity of each other.  
g Redundant data included in a safety -related message to permit data corruptions to be detected by the safety -related transmission function.  
h These failure modes are of random and systematic nature.  
i See Table R. 1 or Table R.2 , component 6, with respect to external communication.  
j Masquerade: Making an inauthentic message  look like an authentic message  by an unauthorized user. 
  – 206 – IEC 60335- 1:2020 © IEC 2020                    U.3.6 The safe operation of an appliance shall not depend on remote communication . 
Compliance is checked by evaluation according to U.3.2. In case of doubt, remote 
communication  shall be rendered inoperative for the relevant tests of this standard.  
U.3.7 Cryptographic techniques shall be implemented to provide data integrity  protection  
once authorization  for remote communication is established.  
The cryptographic  techniques  employed shall  be part of the appliance  including  its 
accessories,  and not rely  upon part of the router or similar  data transmission  device  itself,  
and shall  be performed prior  to transmission.  
NOTE  Examples of commonly accepted data integrity protection are defined and described in ISO/IEC  9796, 
ISO/IEC  9797, ISO/IEC  9798, ISO/IEC  10118, ISO/IEC  11770, ISO/IEC  14888, ISO/IEC  15946, ISO/IEC  18033, 
ISO/IEC  29192, as well as ISO/IEC  19772.  
Compliance is checked by inspection and review of technical documentation which proves 
adherence to the commonly accepted data integrity protection  methods.  
U.3.8 Provisions shall be taken to ensure that software updates provided by the manufacturer 
and tr ansmitted to the appliance via  remote communication shall be verified prior to its  
installation : 
– against corruption through communication;  
– that the software version is compatible with the appliance for which the software version 
was designed.  
Additionally, the software which performs the above -mentioned checks shall contain measures 
to control the fault/error conditions specified in Table R. 1. 
Compliance is checked by evaluating the software and the manufacturer’s version management 
documentation in accordance with the relevant requirements of normative Annex  R. 
U.3.9 Permission for each installation of software in the appliance shall be given by the person 
responsible for the appliance.  
User activation of a mode that enables automatic software updates is permitted.  
Compliance is checked by inspection of technical documentation describing the permission procedure or by functional test.  
U.3.10 The installation  of software shall not impair compliance with the requirements of this 
standard during or after installation.  
Compliance is checked by software inspection and relevant testing.  
 
   IEC 60335- 1:2020 © IEC 2020 – 207 –           Bibliography  
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secondary cells and batteries  
IEC 60086 -1, Primary batteries – Part 1: General  
IEC 60086 -2, Primary batteries – Part 2: Physical and electrical specifications  
IEC 60335 -2-29, Household and similar electrical appliances – Safety  – Part 2 -29: Particular 
requirements for battery chargers  
IEC 60364 (all parts), Low voltage electrical installations 
IEC 60601 (all parts), Medical electrical equipment  
IEC 60721 -2-1, Classification of environmental conditions – Part 2 -1: Environmental conditions 
appearing in nature – Temperature and humidity  
IEC 60730 (all parts), Automatic electrical controls  
IEC 60745 (all parts), Hand- held motor -operated electric tools – Safety  
IEC 60950 -1, Information technology equipment – Safety – Part 1: General requirements  
IEC 60998 -2-1, Connecting devices for low- voltage circuits for household and similar purposes 
– Part 2 -1: Particular requirements for connecting devices as separate entities with screw -type 
clamping units  
IEC 60998 -2-2, Connecting devices for low- voltage circuits for household and similar purposes 
– Part 2 -2: Particular requirements for connecting devices as separate entities with screwless -
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current emissions (equipment input current ≤16 A per phase)  
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IEC 61508 -3:2010 , Functional safety of electrical/electronic/programmable electr onic safety -
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IEC 61508 -7:2010 , Functional safety of electrical/electronic/programmable electronic safety -
related systems – Part 7: Overview of techniques and measures 
IEC 62280, Railway applications – Communic ation, signalling and processing systems – Safety 
related communication in transmission systems  
IEC 62368 -1, Audio/video, information and communication technology equipment – Part 1: 
Safety requirements   – 208 – IEC 60335- 1:2020 © IEC 2020                    IEC 62841 (all parts) , Electric motor -operated hand -held tools, transportable tools and lawn and 
garden machinery – Safety  
CISPR 11, Industrial, scientific and medical equipment – Radio -frequency disturbance 
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CISPR 14 -1, Electromagnetic compatibility – Requi rements for household appliances, electric 
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tools and similar apparatus – Part 2: Immunity – Product family standard 
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scheme giving message recovery  
ISO/IEC  9797 (all parts),  Information technology – Security techniques – Message 
Authentication Codes (MACs)  
ISO/IEC  9798  (all parts),  IT Security techniques – Entity authentication  
ISO/IEC  10118  (all parts),  IT Security techniques – Hash- functions  
ISO/IEC  11770  (all parts),  IT Security techniques – Key management  
ISO/IEC  14888  (all parts),  IT Security techniques – Digital signatu res with appendix  
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techniques based on elliptic curves 
ISO/IEC  18033  (all parts),  Information technology – Security techniques – Encryption algorithms  
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cryptography  
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specifications ISO/IEC Guide 51, Safety aspects – Guidelines for their inclusion in standards  IEC 60335- 1:2020 © IEC 2020 – 209 –           ISO/IEC Guide 71, Guide for addressing accessibility in standards 
  – 210 – IEC 60335- 1:2020 © IEC 2020                    Index of defined terms  
accessible part  ................................ .............   3.6.3  
all-pole disconnection  ...................................  3.8.1  
authentication  ............................................  U.1 .1.1 
authorization  ..............................................  U.1 .1.2 
 
basic insulation  .............................................  3.3.1  
battery  ..........................................................  3.6.9  
battery -operated appliance  ............................  3.5.9  
battery system  .............................................  3.10.1  
built- in appliance ..........................................  3.5.5  
 cell ...............................................................  3.6.8  
charging system  ...........................................  3.10.2  
class 0 appliance  ..........................................  3.3.7  
class 0I appliance  .........................................  3.3.8  
class I appliance  ...........................................  3.3.9  
class II appliance  .........................................  3.3.10  
class III appliance  ........................................  3.3.12  
class II construction  .....................................  3.3.11  
class III construction  ....................................  3.3.13  
clearance  ....................................................  3.3.14  
combined appliance  ......................................  3.5.8  
creepage distance  ........................................  3.3.15  
cryptographic technique  .............................  U.1 .1.3 
 
dangerous malfunction  .................................  3.1.11  
data integrity protection  ..............................  U.1 .1.4 
detachable battery  .......................................  3.6.10  
detachable part  .............................................  3.6.2  
detachable power supply part ........................  3.6.7  
double insulation ...........................................  3.3.3  
 electronic circuit  ...........................................  3.9.2  
electronic component  ....................................  3.9.1  
entity  ...........................................................  3.11.1  
extra- low voltage ..........................................  3.4.1  
 fixed appliance  .............................................  3.5.4  
fully charged  ................................................  3.10.6  
fully discharged ...........................................  3.10.7  
functional insulation  ......................................  3.3.5  
 
hand- held appliance  ......................................  3.5.2  
heating appliance  ..........................................  3.5.6  
 integral bat ter
y ............................................  3.6.12  
interconnection cord  ......................................  3.2.2  
intentionally weak part  ..................................  3.7.8  
 
live part  ........................................................  3.6.4  
 message  ......................................................  3.11.2  
motor -operated appliance  ..............................  3.5.7  
 non- detachable part  ......................................  3.6.1  
non- rechargeable battery  ...........................  B.3.6.1  
non- self-resetting thermal cut- out  .................. 3.7.5  
normal operation ...............................  B.3.1.1; 3.1.9  
 off position ................................ .......................   3.8.2  
outlet load  .....................................................  3.1.12  
 PTC heating element  ........................................  3.8.4  
portable appliance  ...........................................  3.5.1  
protective device  ..............................................  3.7.6  
protective electronic  circuit  ...............................  3.9.3  
protective extra -low voltage circuit  ....................  3.4.4  
protective impedance  .......................................  3.3.6  
public network  ...............................................  3.11.3  
 
rated current  ....................................................  3.1.6  
rated frequency  ................................................  3.1.7  
rated frequency range  ......................................  3.1.8  
rated impulse voltage  .....................................  3.1.10  
rated power input .............................................  3.1.4  
rated power input range  ...................................  3.1.5  
rated voltage  ...................................................  3.1.1  
rated voltage range  ..........................................  3.1.2  
reinforced insulation  .........................................  3.3.4  
remote communication  ...................................  3.11.4  
remote operation ............................................  3.11.5  
room temperature ............................................  3.8.6  
 
safety extra- low voltage ....................................  3.4.2  
safety isolating transformer  ..............................  3.4.3  
self-resetting thermal cut- out ............................  3.7.4  
separabl e battery  ...........................................  3.6.11  
small part  ........................................................  3.6.6  
specified operating region for charging  ............  3.10.3  
stationary appliance  .........................................  3.5.3  
supplementary insulation  ..................................  3.3.2  
supply cord  ......................................................  3.2.3  
supply leads  ....................................................  3.2.1  
 temperature limiter  ...........................................  3.7.2  
thermal cut- out.................................................  3.7.3  
thermal link  ......................................................  3.7.7  
thermostat  .......................................................  3.7.1  
tool .................................................................  3.6.5  
type X attachment  ............................................  3.2.4  
type Y attachment  ............................................  3.2.5  
type Z attachment  ............................................  3.2.6  
 upper limi
t charging voltage  ............................  3.10.4  
user maintenance  ............................................  3.8.5  
 venting  ..........................................................  3.10.5  
visibly glowing heating element.........................  3.8.3  
 working voltage ................................................  3.1.3  
 
 
___________  
 INTERNATIONAL 
ELECTROTECHNICAL 
COMMISSION 
3, rue de Varembé 
PO Box 131 
CH-1211 Geneva 20 
Switzerland 
Tel: + 41 22 919 02 11 
info@iec.ch 
www.iec.ch