I ICS 29.120.99 
K 32 
 
 
National Standard for the People’s Republic of China 
GB 17885—200× 
In replacement of GB 17885-1999 
 
 
  
Electromechanical contactors for 
household and similar purposes 
 
 
 
（IEC 61095:2000, MOD ） 
 
 
（Draft for Approval ） 
 
             
Release on ××/××/200×                                   Implemented on ××/××/200× 
Issued by 
 
General Administration of Quality Supervision,  
Inspection and Quarantine of the People’s Republic of China 
Standardization Administration of the People’s Republic of ChinaGB 17885—200× 
 
 
   Table of Contents 
Introduction 
1 Scope 
2 Standard documents 
3 Terminology and Definition: 4 Classification 5 Features 6 Marking, installations and maintenance 7 Normal usage, installati on and transport conditions 
8 Structural and performance requirements 
9 Test 
Appendix A (Guideline Appe ndix) Contactor Terminal Marking and Identification 
Appendix B (Guideline A ppendix) Procedure Test and Sample Quantity 
Appendix C (Guideline Appe ndix) Instructions for Load Circuit Adjustment 
Appendix D (Guideline Appendi x) Methods for Identifying Short Circuit Power Factor 
Appendix E (Guideline Appe ndix) Measurement of Clear ance and Creepage Distance 
Appendix F (Guideline Appe ndix) Contactor’s Rated Im pulse Withstand Voltage 
Appendix G (Guideline A ppendix) Electrically Heat ed Wire Ignition Test GB 17885—200× 
 
  Introduction 
 
 
All technical contents of this  Standard are compulsory.  
The amendment to the Standard has adopted IEC 61095:2000-10 Ed.1.1, Electromechanical Contactors for Household and Similar Purposes. The technical contents and compiling format 
of this Standard are in compliance with IEC 61095. When adopting IEC 61095:2000-10 Ed.1.1, amendments have been made according to the actual conditions of China. Technical differences have been marked with vertical lines in the 
side margins of the corresponding body texts. Additional notes on the differences of this Standard and IEC are as follows: 
1. 3.6 has been added ，not included in IEC61095 ：2000. 
2. “8.2.6 On and Off Overvoltage” has been removed from IEC 61095 ：2000.10 Ed1.1. 
“5.1g)”, “5.8” and “6.1.2n)” have also b een removed.  Numbering for “9.3.3.5.4” and 
subsequent items have been changed accordingly. 
3. For testing procedures in 9.2.3, see “GB 14048.1-2006, Appendix C”. IEC testing 
procedures are still under discussion.  
4. The output factor in Table 16, IEC 61095 ：2000, was incorrect as ±0. 5. This has 
been amended to ±0. 05 in the current Standard. 
5. 690V rated insulation voltage has been added in Note e for Table 20. 
 This Standard is an amendment for GB  17885-1999, Electromechanical Contactors for 
Household and Similar Purposes. 
The main differences are ： 
1. GB 17885-1999 only contains termi nologies listed in IEC 1095 ：1992, but not in 
GB/T 2900.18—1992. Now all terminologies are included. 
2. “Rated frequency should be in compliance with GB/T 1980” has been removed from 
5.3.3.  
3. 7.1.4 General Condition for Electromagne tic Environment has been added. 
4. 8.1.10 has been amended as “For tes ting procedures in 9.2.3, see “GB 14048.1-2006, 
Appendix C”. 
5. 8.3 Electromagnetic Compatibility has b een added, including 8.3.1 Immunity and 
8.3.2 Emission. 
6. In 9.2.1.6, Chinese wording has been amended for CTI. “CTI for insulation materials 
are essential data for identifying creepage distance” have been removed from 9.2.1.6: 
9.1.2o) and Appendix B, Table B1: E-f. 
7. In 9.2.3, for testing procedures, see “GB 14048.1-2006, Appendix C”.  
8. In 9.2.4.3,  height changed from 75m to 75mm. 
9. 9.2.5.1, 3
rd paragraph: Chinese wording amendment ；5th paragraph: Chinese wording 
amendment. 
10. In 9.2.5.2.2 “spherical surface testing device” ch anged to “spherical testing device” ；
1st，“dropping and oscillating” change d to “dropping or oscillating” ；2nd paragraph: 
“vertical height” changed to “vertical distance”. 
11. 9.2.6 Chinese wording amendment. GB 17885—200× 
 
 
   12. 9.3.3.4.1b) “withstand voltage test not necessary” changed to “impulse withstand 
voltage 
 test not necessary” ；Notes amendments are per GB 14048.1-2006 8.3.3.4.1d). 
13. 9.3.4.2.2 “ …… current limits ……，…… as per maximum Iq of components …… ” 
has been changed to “ …… limited current ……，…… as per maximum allowed peak 
current Ip …… ”. 
14. 9.3.4.2.3 “ …… and Iq current test passed: ”has been changed to “ …… and Iq current 
(if applicable) test passed:” 
15. Addition of Figure 10 Hinge Joint. 
16. Notes added for Appendix A, A.2.2. 
17. Addition of G4 in Appendix G. 
This Standard is in replacement of GB17885-1999. Appendices A-G are as standard. This Standard has been brought forwar d by China Electric Tool Association. 
This Standard is administered by China Na tional Standardization Technical Committee of 
LVEA. Drafted by: Shanghai Electrical Apparatu s Research Institut e (Group) Co., Ltd 
Co-drafted by: Zhejiang Zheng Tai Electri c CO., LTD., Renmin El ectrical Appliance Co., 
Ltd、SASSIN International Electric Co .,Ltd、Delixi Electric Co .,Ltd、Tianshui 213 
Electrical Apparatus Co .Ltd、Schneider Electric (Chi na) Investment Co.,Ltd . 
Drafted by: ZEN Ping, JIA Feng 
Co-drafted by: XIAO Hongwei, GAO Wengl e, SU Hanlin, HUANG Rongrong, ZHENG 
Shiquan, GAO Weidong, ZENG Hui. Replaced earlier version: GB 17885-1999.GB 17885—200× 
 
  Electromechanical contactors for household and similar purposes 
1 Scope 
The standard provides specifications for the use of household and similar 
electromechanical contactors, the main contacts of  which are used to connect to the circuits 
that meet the following requirements: The ra ted voltage does not exceed 440V; the rated 
operating current under the categor y AC-7a is less than or eq ual to 63A, while the current 
limit under category AC-7b is less than or equal to 32A and its rated short-circuit current is 
less than or equals to 6KA. 
The contactors to which the standard applie s are generally not us ed for short-circuit 
breaking current. Therefore the appropriate electrical short-circui t protection should be 
installed as part of it when used. (see 9.3.4) 
This standard does not apply to the following electrical devices: 
a) Contactors in compliance with GB 14048.4 
b) Semiconductor contactors 
c) Contactors for special purpose 
d) Contactor’s auxiliary contact (rele vant requirements see GB 14048.5) 
The requirements of this standard are as follows: 
a) The characteristics of contactors 
b) The contactor shall meet the following requirements: 
1) Operation and performance 
2) Dielectric properties 
3) Housing protection rating 
4) Structure 
5) The properties of EMC 
c) The tests and test methods adopted  to meet the above conditions 
d) Submitting verified test procedures and test sample quantity 
e) The parameters provided by contac tors or by manufacturer samples 
2 Standard documents 
By quoting in this standard, the terms in th e following documents become standard terms. 
Any quoted documents with date s, and all its subsequent amendments to a single (not 
including the contents of corri genda) or revised edition, are not applicable to this standard. 
However, relevant parties who reach an agreement according to the standard are encouraged 
to researches into whether the latest vers ions of these documents should be used. For 
documents without a quoted date, the late st version applies to this standard. 
GB/T 2423.3-2006 Electrical and Electronic Produc ts Environmental Tes ting part II Testing 
method Trial Cab: Constant damp heat test (IEC 60068-2-78:2001, IDT) 
GB/T 2900.18-2008 Electrical terms Lo w-voltage electrical devices 
GB/T 4025-2003 Man-machine interface markings and identification of the basic methods 
and safety rules; Encoding rules of the indicators and operators (IEC 60073:1996, IDT) GB 17885—200× 
 
 
   GB/T 4026-2004 Man-machine interface markings and identification of the basic methods 
and safety rules; General rules on markings of  device terminals and conductor terminals and 
specific alphanumeric system (IEC 60445-1999, IDT) 
GB/T 4205-2003 Man-machine interface (MM I); Operating rules (IEC 60447:1993, IDT) 
GB/T 4207-2003 The measuring methods for CTI and CTI withstand for solid insulated 
materials under moisture (IEC 60112:1979, IDT)  
GB/T 5169.10-2006 Electrical and electronic product fire risk test; Part 10 glow wire/ hot 
wire test method; finished glow wire  ignition test (idt , IEC 60695-2-10:2000) 
GB/T 5465.2-2008 Electrical device graphic symbols Part 2: Graphic symbols (IEC 60417 
DB:2007, IDT) 
GB/T 11020-2005 List of test methods for solid non-metallic materials when exposed to fire 
(IEC 60707:1999,IDT) 
GB/T 11021-2007 Electrical insulation H eat-resistant grade (IEC 60085:2004, IDT) 
GB/T 11026.1-2003 Electrical insulati on material; Heat resistance  
Part 1: Aging procedures and test re sults of the assessment (IEC 60216-1:2001, ID Τ) 
GB 14048.1-2006 Low voltage switch  device and control device  
Part 1: General principle (IEC 60947-1: 2001, MOD) GB  14048.4-2003 Low voltage switch  device and control device  
Electromechanical contactors and motor starter (IEC 60947-4:2000, IDT) 
GB 14048.5-2008 Low voltage switch  device and control device  
Part 5-1 Control circuitry and electrical components  
Switching device control circuit electrical (MOD IEC 60947-5-1:2003) 
GB/T 16895.12-2001 Electrical installations in buildings; Part 4: Security 
Chapter 44: Overvoltage protection  No.433: Atmosphere overvoltage or operating overvoltage protection  
(idt IEC 60364-4-433:1995) 
GB/T 16935.1-2008 Low-pressure system device and insulation coordination  
Part 1: Principles, requirement s and tests (idt IEC 60664-1:2007) 
IEC 60050(151):1978 International Electrotechnical Terminology 
 GB 17885—200× 
 
  Part 151: Electric and magnetic devices 
IEC 60050(441):1984 International El ectrotechnical Terminology  
Part 441: switch device control device and fuse IEC 60050(604):1987 International Electro-technical Vocabulary 
Part 604: Operation of power transmission and distribution 
IEC  60050(826):1982 International Electrotechnical Terminology  
Part 826: Electrical installations IEC 60028 Copper resistance ISO 2039-2-1987 Plastic-hardness identific ation; Part 2: Rockwell hardness 
 
3 Terminology and Definition: 
The standard terminology and the relevant te rminology and definitions specified by GB/T 
2900.18 
3.1 Basic Terminology 
3.1.1 Over-current Any current over the rated current (441-11-06) 3.1.2 Short-circuit Through a low resistor or resist ance, two or more points at different voltage circuit are 
connected accidentally or intentionally  under normal circumstances. (151-03-41) 
3.1.3 Short-circuit current  Over-current caused by a short circuit due to ci rcuit failure or connect ion error. (411-11-07) 
3.1.4 
Overload  
The operating conditions of over-current gene rated in the normal circuit. (441-11-08) GB 17885—200× 
 
 
   3.1.5 
Overload current The over-current that has not been damaged in the circuit. 3.1.6  
Ambient air temperature 
Under the specified conditions, the air temperature surrounds th e entire switching device or 
fuse control. (441-11-13) 
Note: For switching device or fuse that has an  enclosing housing, th e temperature is the 
housing temperature. 
3.1.7 Conductive part  The conductor, but not necessarily part  of current work load. (441-11-09) 
3.1.8 
Exposed conductive part  
Under normal circumstances, the conductive parts, which are easily-reached by  operators, are not live. But under fault condi tions, they can become live. (411-11-10) 
Note: Typical exposed parts such as exposed wall, operating handle and so on. 
3.1.9 Electric shock The physiological and pathologi cal effects that are caused by  the current when it passes 
human or animal body. (826-03-04) 
3.1.10 Live part When the conductor and the conductive parts are normally live, the neutral conductor is 
included. But in common practice, it does not include the PEN conductor. (826-03-01) 
Note: This does not necessarily in clude the risk of electric shock. 
3.1.11 Protective part GB 17885—200× 
 
  In order to prevent electric shock, some measures are taken to connect the required conductor 
to the following components. The connected parts include: 
----------exposed conductive parts 
----------external conductive parts ----------the main terminal ----------ground electrode 
----------power point or artificial neutral point grounding (826-04-05) 
3.1.12 Neutral conductor 
The conductor that is connected to the neutra l point and is capable of transmitting power 
(826-01-03) 
Note: Under certain circumstances, the func tions of neutral c onductor and protective 
conductor are combined at the condition sp ecified. The conductor is called the PEN 
conductor (Symbol PEN) 
3.1.13 Enclosure 
Enclosure can provide a required specified protec tion level to external influences and prevent 
approaching or touching live pa rts or the operating component. 
Note: This definition is similar to the definition of complete circuit IEV 441-13-01 3.1.14 
Integral enclosure 
The integral enclosure belongs to the whol e electrical part an d is indispensable. 
3.1.15  Utilization category With electrical devices or fuses, it accomplishes the combinations that relevant regulation of 
running conditions demands, being used to indica te the actual characteristics of use. (441-17-
19) 
Note: The requirements may include the maki ng (if applicable) and breaking capabilities, 
other characteristics, the circuit connections as well as the condition of use and relevant 
performance. GB 17885—200× 
 
 
   3.2 Switching devices 
3.2.1 Switching device The switching device is one that makes or breaks one  or more electrical circuits in the current. 
(441-14-01) 
3.2.2  Mechanical switching device The mechanical switching device depends on th e motion of detachable contactor to close 
contact or disconnect one or more circuits. (441-14-02) 
Note: Any mechanical switching device can be accordingly named by the medium (for 
example, air, SF6, oil) in which the contactor is open or closed. 
3.2.3 
Semiconductor switching devices The switching devices that c onnect or disconnect circuit current by the controlled 
conductivity of the semiconductor. 
Note: Semiconductor switching device is also us ed to break electri cal current, so this 
definition is different from the definition of IEV441-14-03. 
3.2.4 Fuse When the current exceeds the set value for a long enough time, the circuit and its access 
points are disconnected through the fuse or so me specially designed corresponding parts. All 
the components that formed the complete elect rical devices are include d in fuse. (441-18-01) 
3.2.5  
Circuit-breaker The circuit-breaker is a mechanic switching device, which is not only capable of making, 
loading and breaking the current circuit under normal conditions, but is also able to make, 
load (for a certain period of time) and br eak current under abnormal conditions (such as 
short-circuit) (441-14-20) GB 17885—200× 
 
  3.2.6  
Contactor (mechanical) The contactor is a non-manual operation mechan ical switching device, which is equipped 
with only one position of rest that can make, load and break  current under normal circuit 
conditions (including overload operating conditions) (441-14-33) 
Note 1: The term “non-manual operation” means th at electrical devices can be controlled and 
maintained at an operation by using one or  more of the available external power. 
Note 2: In French, the main contact closes at  the position of rest is often referred to as 
“rupteur”, but in English it has no equivalent. 
Note 3: The contactor is fr equently used in operation. 
3.2.7 Electromagnetic contactor The contactor, which is generated by the el ectromagnet, makes and breaks the main contact 
or breaks the contactor on the main contact. 
3.2.8 Latched contactor The latched contactor refers to a kind of c ontactor that can deter the movable parts from 
returning to the position of rest with the help of latched device  when the actuator loses power. 
(441-14-34) 
Note 1: The latching and releasing of th e latched body could be mechanical, magnetic, 
electric and by gas, etc. 
Note 2: As a result of latched body, it in fact has two positions of  rest. In the strict sense, it 
cannot be defined as a contactor. But its usage an d design are close to thos e of a contactor. So 
it is more appropriate that it meets the requi rements of a contactor on certain occasions. 
3.2.9 Semiconductor contactor (solid state contactor) By use of the semiconductor contactor, the functi on of an electrical contactor can be achieved. 
Note: Semiconductor contact switch can  also include switching device. 
3.2.10  
Pilot switch GB 17885—200× 
 
 
   The pilot switch is a non-manually controlled  switch, which is reac ted under the required 
actuating momentum. 
Note: The actuating momentum can be pressure , temperature, speed, level, time and so on.  
3.2.11 Push-button 
The push-button is an actuator operated by a certain part  of the body (usually finger or the palm of a 
hand) and also is a control switch that is equi pped with resetting function (spring) (441-14-53) 
3.2.12 
SCPD Short circuit protective device SCPD is the device that protec ts circuit or the circuit components from damage by breaking a 
short circuit current. 
3.2.13 
Surge arrester The surge arrester protects th e electrical devices against high transient overvoltage and 
restricts time of afterflo w and amplitude. (604-03-51) 
3.3 Switch electrical components 
3.3.1  
Pole of a switching device It is the electrical pa rt that is only connect ed to a single conductive path of the switching 
device’s main circuit. It does not  include the part that is used to fix all the poles together and 
operate them simultaneously. (441-15-01) 
Note: If the switching device has only one pole, it is known as a unipolar switching device. If 
the switching device is linked t ogether and operated by two or mo re poles, it is referred as a 
multi-polar (bipolar, 3-pole, etc) switching device. 
3.3.2 Main circuit (of a switching device) The main circuit is the switching device’s ma in conductive parts for closing or breaking a 
circuit. (441-15-02) 
3.3.3 Control circuit (of a switching device) GB 17885—200× 
 
  Apart from the main circuit, all conductive pa rts of the switching devi ce that are used for 
closing or breaking a circuit. (441-15-03) 
3.3.4 
Auxiliary circuit (of a switching device) Apart from the main circuit and control circui t, all conductive parts of  the switching device. 
(441-15-04) 
Note: Some auxiliary circuits are used as a dditional functions, such as signal, interlocking, 
etc. At this time, these circuits can also be a part of a control circ uit of another switching 
device. 
3.3.5 
Contact (if a mechanical switching device) For two or more conductors, the circuit is connect ed when they are in contact. They close or 
break the circuit when operated due to their rela tive movements, or keep the circuit connected 
by rotating or sliding th e contacts. (441-15-05) 
3.3.6 Contact piece The contact piece constitutes a part of the conductive parts. (441-15-06) 
3.3.7 
Main contact 
The electrical contact of the main circuit of the switching device, which is carrying the main 
circuit’s current. (441-15-07) 
3.3.8 
Control contact 
The control contact is connected by the control ci rcuit in the electric sw itch, and it is operated 
mechanically by this switching device. (441-15-09) 
3.3.9 Auxiliary contact 
The auxiliary control is connected by the auxi liary contact in the switching device and is 
operated mechanically by this electric switch. (441-15-10) GB 17885—200× 
 
 
   3.3.10 
Auxiliary switch (of a mechanical switching device) The auxiliary switch is a kind of switch that has one or more control and (or) auxiliary 
contacts and is also operated mechani cally by the mechanical switch. (441-15-11) 
3.3.11 “A” contact, make contact “A” contact, a kind of c ontrol contact or auxiliary  contact, closes when the main contact of 
mechanical switch device closes and breaks when the main contact breaks. (441-15-12) 
3.3.12 “B” contact, break contact “B” contact, a kind of control c ontact or auxiliary contact, brea ks when the main contact of 
the mechanic switch device closes, and closes when the main contact breaks. (441-15-13) 
3.3.13 Release (of a mechanical switching device) The release, which is linked with mechanical  switching device, is used to release the 
Retention Mechanism to close or br eak the switching device. (441-15-17) 
Note: The release can be operated instantaneously or with a delay. 
3.3.14 Actuating system (of a mechanical switching device) All the operating component that deliver the actu ating power to the contact of the mechanical 
switching device. 
Note: Actuating system can be mechanic al, electromagnetic, hydraulic, pneumatic 
thermokinetic, etc. 
3.3.15 Actuator 
The actuator is the part that exerts force on the actuating system by external power. (441-15-
22) 
Note: The actuator can be in the form of  a handle, knob, button, trolley or a plunger. 
3.3.16 
Position indicating device GB 17885—200× 
 
  The position indicating device is  a device that indicates whether a mechanical switching 
device is open, closed or (if necessary ) indicates the ground point. (441-15-25) 
3.3.17 
Terminal  The terminal, the conductive part, is  the device that is used to c onnect to the external circuit. 
3.3.18 Screw-type terminal A screw-type terminal is used to tighten and lo osen wires or can also be used to connect two 
or more conductors. The connection can be made using different screws and nuts directly or 
indirectly. 
3.3.19 
Screwless-type terminal 
A screwless-type terminal is used  to tighten and loosen wires or  can also be used to connect 
two or more conductors. The connection can be  made using springs, the cuniform blocks, 
eccentrics or cone wheels di rectly or indirectly. 
3.3.21  Thread-cutting tapping screw Equipped with discontinuous self -tapping screw thread, the sc rew thread can remove the 
material in the hole (see Figure 2 for an example) 
3.3.22 Clamping unit  The clamping unit is essential for the conducto r’s mechanical fasten ing or the electrical 
connection. 
3.3.23 Unprepared conductor The unprepared conductor is a conductor which is chipped and then stripped of its insulation 
for the purpose of inserting into the terminal. 
Note: Conductors whose shape has been adjusted so as to be inserted into terminals, or with 
twisted wires together at the ends, are considered unprepared conductors. GB 17885—200× 
 
 
   3.3.24 
Prepared conductor Conductors that have wires welded together or  cable connectors or loops fitted at their end 
are considered prepared conductors. 
3.4 Operation of switching device 3.4.1 Operation (of a mechani cal switching device) 
Operation refers to moving a contact from one location to the next location. (441-16-01) 
Note 1: As for circuit breaker, it can be a making or breaking operation. 
Note 2: For clarity, the operati on in the electrical sense, for example, making or breaking, is a 
switching operation. But in the sense of opening or closing, for example, is a mechanical 
operation. 
3.4.2  Operation cycle (of a mechanical switching device) 
Operation cycle refers to the continuous operation 
— the conversion from one location to 
another and then return to the position of re st. If there are multiple positions, all other 
positions need to be passed. (441-16-02)  
3.4.3 Operating sequence (of a mechanical switching device) 
In the required time internal, required c ontinuous operations are completed. (441-16-03) 
3.4.4  Automatic control Automatic control refers to unattended operation, which is controlled in accordance with the 
specified conditions. (441-16-05) 
3.4.5 
Closing operation (of a mech anical switching device) 
The device changes from the open position to the closed position. 
3.4.6 Opening operation (of a mech anical switching device) GB 17885—200× 
 
  The device changes from the clos ed position to the open position 
3.4.7 Closed position (of a mechanical switching device) The closed position is the position that ensure s the contact in the main circuit in the 
predefined open position. (441-16-22) 
3.4.8 Open position (of a mechanical switching device) The open position ensures that the breaking contact in the main circuit meets the 
requirements of predefined medi um withstand voltage location. 
Note: The above definition is different from the requirements of the properties of the medium  
specified in IEV441-16-23 3.4.9 Position of rest (of a contactor) 
When the contactor solenoid or compressed air mechanism is not in operation, the position of 
the movable parts is the pos ition of rest. (441-16-24) 
3.4.10 Inching (jogging) Making or breaking the motor or the coil circu it multiple times within a very short time, 
moving the driven mechanism slightly. 
3.4.11 Plugging  To make an operating motor stop or reverse by us ing reverse-phase motor stator windings of 
the motor sequence. 
3.5 Feature measurements  3.5.1 Nominal value The nominal value is the suitable approximate value used to mark or identify a switch or 
electrical components and devices. (151-04-01) GB 17885—200× 
 
 
   3.5.2 
Limiting value  The limited value is a value of the maximum or minimum allowable in norms or standards. (151-04-02) 
3.5.3  
Rated value Under the required operating condition, the value generally given by manufacturers to a 
switch or electrical compone nts or devices. (151-04-03) 
3.5.4 
Rating  A group rating and operating conditions (151-04-04) 
3.5.5 Prospective current (of a circuit and with respect to a switching device or a fuse) 
The prospective current is the current that ma y flow through the circuit when the electrical 
switch or fuse to each pole is  replaced by a conductor whose resistance can be ignored. (441-
17-01) 
Note: The methods used to assess and indicate  current will be specifi ed in the relevant 
standard. 
3.5.6 Prospective peak-current The transient current at the expected peak  after the circuit is  connected. (441-17-02) 
Note: This definition is made under the assumption that an ideal switch is connected, that is, 
one which has infinite resistance during its o ff state and no current lim it during its on state. 
The current can pass through several paths, that is, a multi-polar circuit. This definition 
further assumes that the current at all poles is connected at the same time or even only single 
polar current may be considered. 
3.5.7 
Maximum prospective peak current (of an AC circuit) 
This is the maximum transient prospec tive peak current possible. (441-17-04) GB 17885—200× 
 
  Note: For the multi-polar device in multi-phase  circuit, the maximum prospective current 
only considers one polar. 
3.5.8 
Breaking current (of a switc hing devices or a fuse) 
In the process of breaking, the current flows through one pole of switc hing device or fuse, 
generating the instantaneous flow arc. (441-17-07) 
Note: For AC current, the current is i ndicated by RMS Symmet rical AC Component. 
3.5.9 Breaking capacity (of a switching device or a fuse) Under the specified conditions a nd performance, a switch or fuse can be capable of breaking 
the prospective value of breaking current under a provi ded voltage. (441-17-08) 
Note 1: Required voltage and condition are seen in the relevant  product standards. 
Note 2: AC current is indicated by symmetrical AC component value. 
Note 3: The making capability of  short circuit is shown in 3.5.11. 
3.5.10 Making capacity (of a switching device) Under the specified condition of use and performance, the predic tive making current value of 
the switching device under the specified voltage. (441-17-09) 
Note 1: For specified voltage and condition, see product standard. 
Note 2: For short-circu it making capacity, see 3.5.11. 
3.5.11 Short-circuit breaking capacity 
Under the required condition, the capacity to break, including the short circuit of the terminal 
switching device. (441-17-11) 
3.5.12 Short-circuit making capacity Under the required condition, th e capacity to connect, including the short-circuit terminal 
switching device. (441-17-10) 
3.5.13 GB 17885—200× 
 
 
   Joule integral ( I2t) 
The square of the current over a given time (441-18-23) 
 
3.5.14 
Cut-off current; let-through current 
The maximum transient current gained at the point of breaking the sw itching device or the 
fuse. (441-17-12) 
Note: When the circuit has yet to reach its pr ospective peak current, the concept of breaking 
the switching device or the fuse is particularly significant. 
3.5.15 Applied voltage (for a switching device) Before the current accesses, the applied voltage  is added at two poles between terminals. 
(441-17-24) 
Note: This definition is applicable to a singl e pole device. For a multi-polar device, applied 
voltage means the relative phase vol tage of the device power terminal. 
3.5.16 
Recovery voltage The voltage occurred at one polar  of the switching device or betw een the terminals of the fuse 
after breaking the current. (441-17-25) 
Note 1: The voltage can be considered as two consecutive stages, namely the transient 
recovery voltage and frequency or power fr equency or steady-state recovery voltage 
Note 2: This definition is applicable for a single pole device. For a multi-polar device, 
applied voltage means the relative phase voltage of the device power terminal. 
3.5.17 Transient recovery voltage (abbrev:TRV) 
The recovery voltage with obvious features  of transient at the time. (441-17-26) 
Note: Transient voltage can be oscillatory or non-oscillatory or a combination of the two, 
which depends upon the features of the circuit,  switching devices or fuse transient voltage, 
including the multi-phase neutral point voltage shift. 
3.5.18 GB 17885—200× 
 
  Power frequency recovery voltage 
Recovery voltage after th e disappearance of the tran sient voltage (441-17-27) 
3.5.19 DC steady-state recovery voltage 
Recovery voltage after the disappearance of the transient vol tage in DC circuit. If ripple 
exists, the voltage can be indicated by the average value. (441-17-28) 
3.5.20 Clearance The shortest straight-line dist ance between two conductive parts with a potential difference. 
(441-17-31) 
3.5.21 Creepage distance The shortest distance along th e surface of the insulating ma terial between two conductive 
parts with a potential difference. 
Note: The segment between the two insinuating parts is considered as one part of the surface. 
3.5.22 Working voltage Refers to the maximum AC voltage  or DC voltage that occurs in  part of any insulation end at 
the highest rated power supply voltage, when  it is open-circuit or  under normal operating 
conditions and transient phenomenon is not taken into account. 
3.5.23 
Switching overvoltage Due to a specific operation or a fault in the system, at a certain lo cation in the system  
the transient overvoltage occurs 3.5.24 Impulse withstand voltage Under the required test conditions , the highest impulsive voltage of a certain shape or polarity 
that does not cause disruptive discharge is re ferred to as impulse highest peak voltage. 
3.5.25 GB 17885—200× 
 
 
   Power-frequency withstand voltage 
Under the required test conditions , the value that does not cause  the disruptive discharge of 
the power frequency sine voltage. 
3.5.26 Pollution Any solids, liquid or gas (free gas) that can aff ect the dielectric strength or surface resistivity 
of the external material. 
3.5.27 Pollution degree (of environmental conditions) The classification of environmental conditi ons is according to the magnitude of the 
conductive dust or moisture absorption dusts, free  gas or salt and rela tive humidity, and the 
frequency of the occurrences of the decrease of surface dielectr ic strength and / or resistance 
due to moisture absorption.  
Note 1: The pollution degree of the exposed devi ces is different from the pollution degree in 
the macroeconomic environment, which provides  enclosure or internal heating to prevent 
moisture absorption. 
Note 2: The pollution degree in this standard  refers to the pollution degree in micro-
environment. 
3.5.28 Micro-environment 
Ambient conditions of the clearance and creepage distance.  
Note: The micro-environment of the clearan ce or creepage distance affects the insulation, 
rather than the device environment. The micro- environment might be better or worse than the 
device environment, including all the factors that affect insulati on, such as climatic 
conditions, electromagnetic conditio ns, or pollution degree, etc. 
3.5.29 Overvoltage category (of a circuit or within an electrical system) 
The classification is based on the prospect ive transient overvolta ge and the methods 
restricting overvoltage in the rest rictive (or control) circuit (or electrical system with different 
nominal voltage). 
Note: In an electrical system, the conversion from an overvoltage cat egory to another lower 
overvoltage category is achieved through lowe ring the transient overvoltage to a lower GB 17885—200× 
 
  overvoltage category surface. For example, use overvoltage protection or a combination of 
connections in series and in parallel.  
3.5.30 
Co-ordination of insulation On one hand, the insulating properties of the elec trical device are relate d to the characteristics 
of the expected overvoltage and overvoltage protection device. On the other hand, they are 
related to the expected micro-enviro nment and the pollution protection method. 
3.5.31 Homogeneous (uniform) field This refers to the electric fields where the elec trode voltage gradient is basically constant. For 
example, between two balls, the radius of each ba ll is larger than area of the electric field. 
3.5.32 Inhomogeneous (non-uniform) field Refers to the electric fields where the el ectrode voltage gradient is not constant. 
3.5.33 Tracking 
With the combination of electric stress and el ectrolysis impurities, th e conductive circuit of 
the surface of the solid insulating materials is gradually formed. 
3.5.34 Comparative tracking index (CTI) 
The maximum voltage (volt) under which the material can undertake 50 electrolyte drops 
without showing the marks of tracking. 
Note 1: Each test voltage value and th e value of CTI should be divided by 25. 
Note 2: The above definiti on is based upon GB/T 4207-2003 2.3. 
3.6 Signs 
a) Ic: Making and breaking the current 
b) Ie: Rated operating current c) Ur: Power frequency recovery voltage d) Ue: Rated operating voltage GB 17885—200× 
 
 
   e) cosΦ: Power factor 
f) Uimp: Rated voltage impulse tolerance g) Ui: Rated insulation voltage h) SCPD: Short circu it protection device 
i) SELV: Secure ultra-low voltage 
j) CTI: Comparative tracking index 
4 Classification 
Contactors in 5.2 in this standard can be  used as the basis for classification 
5 Features 
5.1 Feature overview 
Features must be indicated by the following items: a) The type of the contactor (see 5.2); b) The rated value and restrictive value of the main circuit (see 5.3); 
c) Usage categories (see 5.4); 
d) The control circuit (see 5.5); e) The auxiliary circuit (see 5.6); f) The performance under short-circuit conditions (see 5.7); 5.2 The type of the contactors The requirements are as follows  (also in reference to 6): 
5.2.1 Polar 
5.2.2 Control method 
a) Automatic (controlled by indicator switch or program-controlled); b) Non-automatic (for example, manual operation or button operation); 
c) Semi-automatic (partly automa tic and partly non-automatic). 
5.3 The rated value and restrictiv e value of the main circuit 
The rated value of the contactors and starters should be indicat ed as per 5.3.1 to 5.4 and 5.7 to 
5.8, which can be increased or decreased according to the need. GB 17885—200× 
 
  5.3.1 Rated voltage 
The contacts provide for th e following rated voltage. 
5.3.1.1 Rated operating voltage (U e) 
The rated voltage of the contacto r, a value that determines the use of the contactors with the 
combination of the rated operating current is rela ted with the relevant test and usage category. 
For a single pole contactor, the vo ltage at cross-polar ends (cont act disconnect location) is 
generally stipulated as rated operating voltage. For multi-pole contactors, the phase voltage is 
stipulated as rate d operating voltage. 
Note 1: By different jobs and usage category, contactors can be used to determine multiple 
rated voltage and rated ope rating current or power; 
Note 2: By different jobs and usage category, contactors can be used to determine multiple 
rated voltage and relevant ma king and breaking capabilities; 
Note 3: That the operating voltage in the c ontactors is different from its actual operating 
voltage must be notified. 
5.3.1.2 Rated insulation voltage （Ui） 
The rated insulating voltage of the contactors is a voltage value that is related to dielectric test 
voltage and creepage distance. 
Under no condition should the maxium value of  the rated operating voltage exceed the value 
of the rated insulating voltage. 
Note: Regarding the contactors that have b een provided for rated insulating voltage, the 
maximum of their rated operating voltage is considered as the rated insulating voltage. 
5.3.1.3 Rated impulsive withstand voltage (U imp) 
Under the required test cond itions, the impulse voltage p eak, which the contactors can 
withstand without disruptive discharge with th e provisions of the shap e and polarity. It is 
related to the electric clearance. 
The rated impulse tolerance volta ge of the contacts should be equal to or greater than the 
transient overvoltage value generated in the circuit. 
Note: For priority value of the rated impulse voltage value, see Figure 18. 
5.3.2 Current or power The contactors specify the following types of current: 
5.3.2.1 Free air thermal rated current (I
th) GB 17885—200× 
 
 
   Free air thermal rated current is the maximu m test current value for the non-enclosed 
contactors when performing the te mperature rise test (see 9.3.3.3). 
Free air thermal rated current is at least equa l to the maximum rating operating current value 
(see 5.3.2.3) of the non-enclosed contact unde r 8-hour operating c onditions (see 5.3.4.1). 
Atmospheric conditions should be interpreted as  normal interior conditions, without external 
radiation, ventilation or air condition. 
Note 1: Free air thermal rated current is not a rated value and does not need to be marked on 
the device. 
Note 2: The non-enclosed contactors are thos e that are not provided with housing by the 
manufacturer, or the housing provided is  not designed for contactor protection. 
5.3.2.2 Enclosed thermal rated current （Ithe) 
Provided by the manufacturer, enclosed ther mal rated current is used to conduct the 
temperature rise test for the c ontactors installed in the housing.  If the manufacturer specifies 
that the contactor is a closed, usually used w ith one or more specified housing types and sizes, 
the enclosed thermal rated current test mu st be performed. The test should adopt the 
minimum size housing (see 9.3.3,3). The enclosed th ermal rated current should be at least 
equal to the closed contactor’s maximum vo ltage value in 8 hour operating conditions (see 
5.3.2.3). 
If the contactor is usually in the non-specified  housing and the enclosed thermal rated current 
test has already been conducted, then the enclos ed thermal rated current may not be needed, 
in which case the manufacturer should provide guide for this. 
Note 1: Enclosed thermal rated current is not ra ted value, so it does not need to be marked on 
the device; 
Note 2: Closed contactors refer to the contac tor that is usually used with one or more 
specified housing types and sizes or with different types of housings. 
5.3.2.3 Rated operating current (I e) rated operating power 
The rated operating current of the contactor is specified by the manufacturer. The following 
factors should be taken into consideration when determining the rated operating current: 
Rated operating voltage (see 5.3.1.1); Free air therma l rated current, or the enclosed thermal 
rated current value,; rated frequency (see 5.3.3) ; rated operating conditions (see 5.3.4); usage 
category (see 5.4) and the type of protector. 
Separate motor contactors can be connected  and disconnected dire ctly. Rated operating 
current can be replaced or supplemented by th e maximum rated output power of the motor 
controlled by this contactor. Manufacturer should provide for the assumptive correlation 
between the current and power. GB 17885—200× 
 
  5.3.3 Rated power 
Used in contactor design and its corresponding power frequency. 
Note: One contactor can have a group of ra ted frequencies or rated frequency ranges. 
5.3.4 Rated working time 
The rated working time is made up of the following: 
5.3.4.1 8-hour working time This system means the main contact remains closed and carries constant current long enough 
to enable the contactor to achieve thermal equilibrium, but breaking must be effected after 8 
hours. 
Note 1: This is the basic working time to determine the contactor’s I
th and I the. 
Note 2: The breaking is effect ed by current breaking device. 
5.3.4.2 Intermittent cycle or intermittent working time There is a set ratio betw een the time with load and time w ithout load while the main contact 
maintains closed. It is a very short time and not enough to enable the connector to achieve 
thermal equilibrium.  
Intermittent working time is characterized by the current value, the hourly operating cycle 
and load factor. The load factor is the rati o of the power time and entire cycle, usually 
indicated as a percentage. 
According to the frequency of the operation cycl es they are able to conduct per hour, the 
contactors can be classified  into the following priority: 
 Grade  times of operation (per hour)  1  3 
 3  3 
 12  12  30  30  120  120  300  300  1200  1200 The contactors that are used for the intermitte nt working time can be named on the basis of 
the characteristics thereof. GB 17885—200× 
 
 
   For example: 5 min in each 2 min have 32A cu rrent passing through, the intermittent working 
time can be expressed as: 32A, 12A, 40% 
5.3.4.3 Short-term working time 
The time for the main contact to keep closed is not long enough for th e contact to achieve 
thermal equilibrium. Time with load is divi ded by the time without load. And the time 
without load is long enough to enable the temper ature of the contactor to  recover to the same 
ambient temperature of the medium. 
5.3.4.4 Cycle working time 
With cycle working time, an operation is conducted regularly and repetitively for both 
constant load and variable load. (151-04-11) 
5.3.5 The characteristics of normal load and overload This specifies the requirements for the ra ted value under the normal load and overload 
conditions. For details, see 8.2.4. 
5.3.5.1 The overload current breaking cap ability of the withstand motor 
The contactor should be able to withstand thermal stress generate d by the start-up and 
acceleration of the motor and overload. 
For detailed requirements, see 8.2.4.3. 5.3.5.2 Rated making capacity A variety of usage category’s (see 5.4) requi rement can be referred to in 8.2.4.1. Only when 
the contactors are operated according to the requirements in 8.2.1.1 and 8.2.1.2 are rated 
making and breaking capabilities valid. 
5.3.5.3. Rated breaking capacity A variety of usage category’s (see 5.4) requi rement can be referred to in 8.2.4.1. Only when 
the contactors are operated according to the requirements in 8.2.1.1 and 8.2.1.2 are rated 
making and breaking capabilities valid. 
5.3.5.4 Rated performance Rated performance, see making a nd breaking operations in 8.2.4.2 
5.3.6 Rated restrictive short-circuit current 
The manufacturer’s prospective current value. Under the required test  conditions in 9.3.4 at 
the operating time of electrical devices prot ection, SCPN specified by the manufacturer 
should be able to withsta nd the specified current. 
The details of SCPN should be supplied by the manufacturers. GB 17885—200× 
 
  Note: RMS component values (r,m,s) is used to  indicate the rated sh ort circuit restrictive 
current. 
5.4  Usage category 
The usage category of the contacto rs is to determine its utiliz ation and characterized by one 
or more using qualifications in the following. 
Current: indicated by the rated op erating current with a multiple 
Voltage: indicated by the rated operating voltage with a multiple 
Power factors The standard usage category in Table 1     Table 1 Usage category 
Usage Category 
a Typical usage 
AC-7a Low sensitivity load for household 
appliances and similar purpose 
AC-7b Load of the household motor b 
a Contactors can be used for other usage cat egory. Under this condition, the contactors 
should meet the requirements of the usage category specified in GB 14048.4 
b Category AC-7b can be used for a limited ti me for occasional tight joint making and 
breaking (inching) or reverse plugging. In the limited time avai lable, the operation 
frequency should be no more than 5 times per minute or 10 times within a 10-minute 
cycle. 
 
Each category is characterized by the current, voltage, power factor a nd data in Table 8 and 
Table 9, as well as the required test qualifications in this standard.  
Since making and breaking capabilities are directly  related to the usage category in Table 8, it 
is unnecessary to specify for the maki ng and breaking capacity separately.  
Unless specified otherwise, contactors in AC -7b usage category should be designed according 
to the motor’s starting characteristics related to  the making capability (see Table 8). When the 
starting current of the electri cal rotor and the motor exceed  the values in Table 8, the 
operating current of the contactor should be reduced accordingly. 
5.4.1 Identifying the usage category from the test result Contacts tested on the basis of a usage categ ory or some combination of parameters 
(maximum operating voltage and cu rrent etc) can be used in another usage category without GB 17885—200× 
 
 
   further test, provided that the co ntactor has been tested accordi ng to the parameters in Table 8 
and Table 10. The current used for temperature rise test should be no less than the rated 
operating current of the  selected usage category under extended use and the various 
parameters and test circuits s hould be less demanding than the te sts that have previously been 
carried out. 
5.5 Control circuit The features of the control circuit: a) Current category; 
b) Rated frequency;  
c) Rated control circuit voltage U
c (property and frequency); 
d) Rated control power voltage U s (property and frequency); 
e) The application of connec ting to the SELV circuit. 
Note: The difference between the two voltages in (c ) and (d) is that the former is the voltage 
between the two ends of the contactor (a cont actor) (see 3.3.11) in cont rol circuit, while the 
latter is the voltage applied on the terminals in a contactor co ntrol circuit. Because of its 
appearance in transformers, rectifiers, resistors,  etc, the control power voltage is different 
from the control circuit voltage. 
Rated control circuit voltage a nd rated power (if app licable) are the parameters to determine 
the characteristics of the actuation and te mperature rise in the control circuit. 
5.6 Auxiliary circuit The features of the auxiliary ci rcuit includes the quantity and category of the contactors in 
every circuit (a contactor, b contactor) as well as the rated value specified in GB 14048.5. 
5.7 The performance under short-circuit condition 
The contactors should be marked by its SCPD’s type, rated value and characteristics in order 
to prevent short circuit. Its re quirements are specified in 8.2.5. 
6 Marking, installations and maintenance 
6.1 The type of marking  
The manufacturer should provi de the following markings: 
6.1.1 Nameplate a) The factory’s name or trademark b) Product name, model or serial number GB 17885—200× 
 
  c) The standard number it complies w ith (such as factory statement) 
6.1.2 Features, basic rated value d) Rated operating voltage (see 5.3.1.1); e) Usage category and rated operating current or  rated power at the rated operating voltage 
(see 5.3.2.3 and 5.4); 
f) Rated frequency (for example: 50Hz or 50Hz/60Hz); g) Rated operating time and intermittent operatin g time classification (if any) (see 5.3.4); 
h) Rated making and breaking capacity. This parame ter can be replaced by usage category (if 
applicable) 
Security and installation: i) Rated insulation voltage (see 5.3.1.2); j) Rated impulsive withstand voltage (see 5.3.1.3) (if required); 
k) The degree of the housing protection (see 8.1.10) (IP symbol); 
l) Pollution degree (see 7.1.3.2); 
m) Rated short-circuit current (see 5.3.6) and the model of SC PD and the rated current value 
and characteristics, control circuit (see 5.5) (should be marked on the contactors or coils): 
n) Rated control circuit voltage (U
c), the type of the cu rrent and rated power; 
o) If necessary, rated control power voltage (U s), the type of the current and power. 
The control circuit connected to SELV 
p) The adaptability of the control circuit conne cted to SELV power; The power voltage to the 
main circuit is higher than that to the SELV. 
Auxiliary circuit: 
q) Auxiliary circu it ratings (see 5.6). 
6.2 Markings Markings should be durable  and easy to identify. 
In order to guarantee access to all data from the manufacturer, the name of the manufacturer 
or trademark, product name and model or serial  number should be marked on the contactor, 
better at the contactor’s nameplate. 
Note: In American and Canada, rated opera ting voltage may be marked as follows: GB 17885—200× 
 
 
   a) When the electric equipment is used in the three-phase four-wire systems, the phase 
voltage and line voltage should be marked  at the same time, for example 277/480V. 
b) When the electric equipment is used in th e three-phase three-wire systems, phase voltage 
should be marked, for example 480V. 
The contactor should also be marked with the fo llowing data and it should be easy to see after 
installation: 
——the direction of movement of the actua tor (as shown in 8.1.4.2) ( if applicable); 
——the location markings of the actuator (as shown in 8.1.5.1 and 8.1.5.2); ——Qualification markings or  certification markings 
——For micro-contactor, symbols, co lour code or alphanumeric code; 
——Identification and markings of  terminals (as shown in 8.1.6.4); 
——IP code and anti-electric shoc k protection level (if applicable ), should be marked on the 
contactors if possible 
The k) in 6.1 should be marked on the housing, c) and qualification mark ings (or certification 
markings) should be marked on the nameplate. The data in d) ~ j), l) ~ j) should be marked on 
nameplate or contactors or on the rele vant documents from the manufacturer. 
The markings of terminals can be seen in Appendix A Markings should not be placed on screws, remova ble pads or other removable components.  
Note: Additional usage category in GB 14048.4 may al so be marked up on the contactors (see 
Note 1) 
6.3 Description of installatio n, operation and maintenance  
Manufacturer shall provide the repairing conditio ns in its documentation or samples for the 
installation, operation, and c ontactor operation or repairing after the failure.  
If necessary, specifications should be provided in the manuals for contactor transportation, 
installation and opera tion, on how to install, use and operate the contactor. 
The above mentioned documents should provide  the specifications on the level and the 
frequency of recommended re pairing (if applicable).  
7 Normal usage, installation and transport conditions 
7.1 Normal usage conditions 
Contactors meeting the requirements of this standard can be operated in the following 
conditions: GB 17885—200× 
 
  7.1.1 Ambient air temperature 
The highest ambient air temperature is +40 ℃ and the average temperature does not go above 
+35℃ during the 24h. The minimum ambient air temperature is -5 ℃. 
For contactors without housing, the ambient air temper ature is the temperature of the ambient 
air. For contactors with housing, the ambient air temperature is the temperature of the 
housing. 
Contactors used at the ambien t air temperature exceeding +40 ℃ (especially in tropical 
countries) and lower than -5 ℃ should be specially designed for use according to the 
requirements provided with factory samples. 
7.1.2 Altitude  The altitude of the installati on site should not exceed 2,000 m 
If a contactor is lo cated at a height of more than 2,000 m, the decline in dielectric strength 
and the role of air-cooling need to consider ed. On such occasions, contactors should be 
specially designed for use according to the re quirements provided with factory samples. 
The data given by the manufacture can substitute the rules above. 
7.1.3 Atmospheric conditions 7.1.3.1 Humidity 
Maximum temperature is +40
℃, and relative humidity should not be more than 50%. At 
lower temperature, a higher relative hu midity is allowed. For example, at +20 ℃ the relative 
humidity can be at 90%. Measures should be taken to account for moisture which appears 
during changes of temperature. 
Note: The environmental conditions of the pollution degree defined in 7.1.3.2 is more 
accurate.  
7.1.3.2 Pollution degree Degrees of pollution (as shown in 3.5.27) are rela ted to the environmental conditions of the 
contactor.  
Note: The micro-environment of clearance and creepage distance determ ines the impact of 
the insulation, rather than the environment of the contactor. The micro-environment of 
clearance and creepage distance may be better or  worse than the envir onment of the contactor. 
Micro-environment includes all the factors that affect the insulation, such as weather 
conditions, electromagnetic condit ions or pollution and so on. GB 17885—200× 
 
 
   For contactors in housing or the contactors whose housing is the in tegral part of the contactor, 
environmental pollution degree within  the housing should be selected. 
In order to identify the clearance or creepage distance, micro-environment pollution can be 
divided into the following four  degrees (For clearance or cr eepage distance of different 
pollution degrees, see Tables 19 and 20) 
Pollution degree 1: No pollution or  only dry non-conductive pollution. 
Pollution degree 2: In general, only non-conductive pollution, but  the accidental short-term 
conductivity caused by moisture must be taken into account. 
Pollution degree 3: Conductive pollution: the dr y non-productive pollution will be turned into 
conductive pollution due to the moisture. 
Pollution degree 4: Persistent conductive pollution: for example,  due to conductive dust or 
rain, snow pollution. Contactors for household or similar purposes  are generally applicable 
for pollution degree 2. 
7.1.4 General conditions of electromagnetic environment 
In general, this refers to the environment re lated to the common low-voltage power grid, such 
as: civil, commercial, light industr ial sites and (or) similar usage. 
7.2 Transport and storage conditions Unless there are other provisions, the following te mperature is applicable  for transporting and 
storing: -25
℃ to +55 ℃, or +70 ℃ (short time, i.e. within 24 hours). 
7.3 Installations 
The contactors should be installed acco rding to the provisions of the factory. 
8 Structural and performance requirements 
8.1 Structural requirements 
Contactors with housing, rega rdless whether it is part of th e contactor, should be designed to 
withstand the stress aris ing from installation and normal us age. In addition, it should have 
abnormal heat resistance and ignition risk protection. 
Note: Enclosed contactor with housing is a ki nd of contactor insta lled in a housing. There 
should be only one contactor in each housing. 
8.1.1 Materials 
All materials of the contactor s hould be able to pass the follow ing test for usability. The test 
should be conducted on the contactor and (or) on the parts of the contacts (if it cannot be 
conducted on the contactor) GB 17885—200× 
 
  a) Anti-aging test (see 8.1.1.1); 
b) Damp resistance test (see 8.1.1.2); 
c) Heat resistance test (see 8.1.1.3); 
d) Abnormal heat resistance and ignition risk test (see 8.1.1.4); 
e) Rusting resistance test (see 8.1.1.5); 
The heat resistance test and abnormal heat resist ance and ignition risk test are best conducted 
on the contactors or the appropr iate parts of the contactors. 
In some cases, the test can be carried out  on materials instead of the contactors. 
8.1.1.1 Anti-aging tests The elastic parts (for example: lining, seal, cove r films and spiral pad, etc) of the contactors 
made from rubber, PVC and similar thermopl astic materials should have the anti-aging 
properties. 
The test methods are shown in 9.2.1.1. 8.1.1.2 Damp resistance test Contactors should be able to resist the impact of damp in normal use. 
For test method, see 9.2.1.2. 8.1.1.3 Heat resistance test 
Closed, semi-closed and non-closed  contactors, away from all th e live parts, should not be 
affected by the highest temperature. 
The test methods are shown in 9.2.1.3 and 9.2.1.3.2. 8.1.1.4 Abnormal heat resistance and ignition risk test 
Because of the effects of the thermal stress generated by electric effect, the parts of the 
insulating material might cause the degradati on of the contactor’s security. These parts 
should not be affected by abnormal heat and ignition. 
The test methods are shown in 9.2.1.4. 
If tests must be conducted at many places in a sample, it should be noted that the damage 
caused by a previous test should not affect a subsequent test. For parts with a surface less 
than 14 mm x 14 mm, the tests are not necessary. 
8.1.1.5 Rusting resistance test The black metal parts of the contactors shoul d have anti-rusting pr otecting, including the 
housing and cover (except for the electromagnetic pole surface) 
For test method, see 9.2.1.5. GB 17885—200× 
 
 
   8.1.2 The strength of screws and nuts for instal lation and maintenance ( not for the terminal 
block) 
When the required operating screw or nut ar e installed and maintained according to 
manufacturer’s illustrations, it should be able  to withstand mechanic stress of normal use. 
For the self-tapping screws and thread-cutti ng tapping screws that are used only as a 
mechanical combination of the extrusion-type: if they are screwed into the board, the two 
screws should be able to withstand the mechanical stress of normal use. 
Self-tapping screws of extrusion type are s hown in Figure 1, while th e thread-cutting tapping 
screws are shown in Figure 2. In addition, se lf-tapping screws and thread-cutting tapping 
screws operated by the installer should be  attached by relevant auxiliary parts. 
The screw or nuts that transfer contac t pressure should have metal thread. 
For electrical connection, the contact pre ssure should not be transferred through the 
insulating material (but other materials like ceramics that are capable of compensating any 
shrinkage or deformation are excluded). 
The above requirements should be observ ed and tested as specified in 9.2.2. 
8.1.3 Electric clearance and creepage distance 
a) For the contactors, which has been provided for Uimp (see 5.3.1.3) by the manufacture, the 
minimal electric clearance is shown in Table 19 and the minimal creepage distance is shown 
in Table 20. 
The two are relevant to the Ui. Its testing methods are shown in 9.3.3.4.1. b) For the contactors, which has not been provided with Uimp by the manufacture, its 
minimal electric clearance and creep age distance should not be le ss than the required values 
in Table 2, when the contactors are installed for normal use. 
The testing methods are shown in 9.3.3.4.2. 
c) For SELV circuit, minimal clearance or cr eepage distance are stil l under consideration. 
The requirements of the dielectr ic properties are shown in 8.2.3. 
Note 1: The different live parts of the contactors, which can be installed close to each other, 
should be provided with enough clearance. 
Note 2: For the contactors whose control circuit is to be conn ected to ultra-low power supply, 
when the voltage provided by the main circuit is  greater than the ultra-low security voltage, 
the electric clearance and creepage distance of the control circu it and the main circuit should 
be greater than or  equal to 6mm. GB 17885—200× 
 
  Its testing methods are shown in 9.3.3.4.2 
8.1.4 Actuator The requirements in 8.1.4.1 and 8.1.4.2 are applicab le to contactors with a manual operating 
actuator. 
8.1.4.1 Insulation The actuator of the contactor should have  good insulation from the live parts and its 
insulation should be determined by the cont actor’s rated insulati ng voltage and rated 
impulsive withstand voltage. In addition, if the actuator is made of metal, it should have a 
good connection with a protective co nductor, unless it has reliable a dditional insulation. If the 
actuator is made of insulating material or cove red up with materials, its internal metal parts 
might be contacted once the insulation is destro yed. Therefore, the parts of the metal should 
be reliably insulated from the live parts, and its insulation also ought to be determined by its 
rated insulating voltage. 
8.1.4.2 Actuating direction 
The actuating direction of the act uator ought to be in line with the requirements in GB/T 4205. 
  Table 2 Electric cleara nce and creepage distance 
Electric clearance  mm 
Difference between the polarity of the 
live components 3 
Live parts and between the exposed 
conductive partsa 3 (6) 
Creepage distance                          mm 
Between separate live parts when contact 
at open positionb 3 
Ue ≤ 250V 3 Live parts with 
different polarity 
250V < U e ≤ 440V 4 
Live parts and between the exposed 
conductive partsa 3 (6) 
a If the electric clearance and creepage distance between the live parts is reduced due 
to the contactor’s at a disadvantageous pos ition, then the value in parentheses should 
be adopted. GB 17885—200× 
 
 
   b Not applicable for auxiliary  and control contactors. 
 
8.1.4.3 Installations 
The actuators which are installed at movable panels or open doors should be properly linked 
up with the associated parts, when the control panel was back in place or when the door is 
closed. 
8.1.5 The markings of open and closed positions 8.1.5.1 Installation instructions When the contactor is marked with open and closed positions, these should be clearly marked. 
For enclosed contactors, this marking can  either be seen or not from outside. 
This can be marked by position indicator. (See 3.3.16) If graphic symbols are used, “1” and “0” should be used to  indicate contactor’s open or 
closed positions respectively. 
The contactor operated by two butto ns should be indicated by th e red colour only when it is 
marked for breaking. Otherwise use symbol “0”. 
No other buttons are allowe d to use the red colour. 
Any buttons, button-type indicator as well as the colour of the i ndicator should be in line with 
the provisions in GB/T 4205. 
8.1.5.2 Actuators used for position indication When the actuator is used to indicate the cont actor position, it should automatically remain in 
the relevant position opposite the contactor. Theref ore, the actuator shou ld have a set of two 
different resting positions that correspond to  the contactor. For auto-disconnecting, the 
actuator can have a th ird different position. 
8.1.6 Terminals 8.1.6.1 Structural requirements All the parts in contact and current loading part s of the terminals should be made from metal 
that has sufficient mechanical strength. 
In order to ensure sustainable maintenance of the necessary contactor pressure, the terminals 
should use effective ways to connect wires, such as screws, springs and others, etc. 
At the appropriate contact surface, the structur e of the terminals should enable wire pressing 
without causing damage to the wires and terminals. GB 17885—200× 
 
  The structure of the terminals should not allow the wires to move, or any movement should 
not affect the normal operation of  the contactor or cause the in sulating voltage to be reduced 
below the rated value. 
The testing methods are shown in 9.2.4.2, 9.2.4.3, 9.2.4.4. Note: North American countries have specifi c requirements regarding the terminals or 
markings that are suitable for aluminium conductors. 
8.1.6.2 The ability to connect to wires The manufacturer should indicate the type of wi re suitable for connecting terminals (hard line 
or soft line, single-core, or multi-strand wi re), the wire’s maximum and minimal cross-
section and the numbers of wires that can c onnect the terminals at the same time. The 
maximum cross-section of the terminals to c onnect to the wires should be no less than the 
requirement in 9.3.3.3. The terminals should be able  to connect to at le ast two wires of the 
same type with a smaller cross-section, as is specified in Table 3. 
(Table 3 lists the standard cross-section of  round copper wire, and also shows the general 
correlation of the ISO Metric  and AWG/MCM wire gauge.) 
 
Table 3 The standard cross-se ction of round copper wire 
The cross-section of the 
ISO wire AMG/MCM 
mm2 Gauge No Equivalent cross-section  
mm2 
0.2 
-a 
0.5 
0.75 
1 
1.5 
2.5 
4 6 24 
22 20 18 
-
 a 
16 
14 12 10 0.205 
0.324 0.519 
0.82 
-
 a 
1.3 
2.1 3.3 5.3 GB 17885—200× 
 
 
   10 
16 25 35 8 
6 4 2 8.4 
13.3 21.2 33.6 
a When considering the wiring capacity, the short line is seen as a gauge. 
 
8.1.6.3 Terminal connection 
The terminal should be easily to  accessible and easy to wire. 
The screws and nuts clamping the terminal and th e wires should not be used for other parts. 
8.1.6.4 Identification and markings of the terminals  The markings of the terminal, specified in GB/T 4026, should be clear and durable. 
The terminal specifically used for connecting to  the neutral wire should be marked with the 
letter “N” for identification. 
The identification and markings for ground pr otection terminals ar e specified in 8.1.8.3. 
Additional requirements of the termin als can be seen in Appendix A. 
8.1.7 The additional requirements for the contactor with neutral polarity. 
If the contactor has one pole to connect to the neutral point, it should be marked with letter 
“N” clearly for iden tification (see 8.1.6.4). 
The neutral polarity is not allowed to be disc onnected before other po larities, or to be 
connected later than others. 
Free air heating current contract is the same to all the poles. 
8.1.8 Specifications of ground protection 8.1.8.1 Structural requirements Exposed conductive parts and components (such as: floor, frame and the fixed metal piece, 
excluding components that do not pose dangers ), should be connected with each other 
electrically and connected to th e ground protective terminals. The requirements are applicable 
to contactors used independently an d also to the contactor assemblies. 
If the exposed conductive parts cannot be cont acted by hand, or cannot be held by hand, or 
their size is very small (about 50 mm × 50 mm) or  located at the positio n that has no contact 
with the live components, such as screws, na ils, nameplate, transformer iron core, certain GB 17885—200× 
 
  parts of electromagnet and releas e parts, they are considered to pose no dangers regardless of 
their size. 
8.1.8.2 Ground protective terminals 
Protective terminals should be eas ily accessible, easy to wire and can remain connected to the 
electrode or ground even when the cover a nd any other removable parts are removed. 
Protective terminals should have the appropriate anti-wearing protection. 
For the contactors that are equipped with c onductive frames and housing, measures must be 
taken to ensure that there sti ll exists electrical continuity between th e exposed conductive 
parts of the contactors and metal sheath. 
Protective terminals cannot be used for other purposes. Only when it is connected to PEN 
(see in 3.1.12) can the terminal of PEN not onl y used for protective grounding, but also used 
as neutral wire terminal. 
8.1.8.3 The markings and identification of the protective terminal The markings for protective termin al should be durable and clear. 
According to the provisions in GB/T 4026-2004 5.3, protective terminals should be identified 
by adopting colour markings (green-yellow ma rkings) or symbol PEN or markings on the 
devices with graphic symbol s under the condition of PEN. 
Symbol as specified  in GB/T 5465.2:  
Protective grounding 
Note: The former recommended symbol 
  should gradually be replaced by the symbol 
above. 
8.1.9 Housing The following requirements are only applicable to housings used together with the contactors. 
8.1.9.1 Design 
The housing should be designed in such a way that when open or ot her protective parts 
having been removed, all parts for installation and maintenance are easy to access. 
In order to enable the external wires enter th e housing and to ensure a good connection, there 
must be enough space left in the housing. 
The fixed part of the metal housing and th e other exposed conductive parts should be 
electrically connected and even connected  to the ground terminal, ensure a good ground 
connection or connection to th e ground protective c onductor. When the in stallations of the GB 17885—200× 
 
 
   housing’s removable metal parts are in place, they should not  be installed from the ground 
terminals and the removable parts are fixed firm ly at a fixed place in the housing in order to 
prevent the accidental release or loss due to the contacto r’s operation or vibration. 
The housing, which has housing protection degree IP1 to IP4 (includingIP4), should be left 
with enough space to set scuppers. The detailed requirements can be referred to in GB/T 
14048.1. 
The housing should have appropriate mechanical strength. (see 8.1.11) 
It is not allowed to open the housing or remove  any parts of the housi ng without the correct 
tools. 
The required housing is consider ed as an irremovable part. 
Removal of buttons from the external housing is is not permitted. 8.1.9.2 Insulation In order to prevent the metal housing from accide ntally contacting with the live parts, some 
or all of the housing should be lined with insu lating materials, which should be firmly fixed 
in the housing. 
Visually inspect whether it is in line with the requirements. 
8.1.10 The housing’s protective degree of the enclosed contactors The requirements and testing methods of the housing’s protective degree of the enclosed 
contactors are shown in appendix C in GB 14048.1-2006 
8.1.11 Impact resistance performance 
The external parts of the closed and semi-c losed contactor and parts of the non-closed 
contactors should be able to withstand the expected impact under normal conditions. 
The testing methods are shown in 9.2.5. 8.1.12 Durability of the markings The markings of the contactors should be clear, easy to identify and durable. 
Testing methods are shown in 9.2.6 
8.2 Performance requirements 8.2.1 Operating conditions 8.2.1.1 The general requirements of the operating conditions The contactors ought to be operated accordi ng to the provisions of the manufacturer. GB 17885—200× 
 
  In operation, every polarity of  the multi-contractors should be  connected and disconnted at 
the same time (See 8.1.7 for neutral) 
8.2.1.2 Actuating range  
The contactor can actuate at any value betw een 85% and 110% of the rated control power 
voltage U s. In this range, 110% U s is the upper limit and 85% U s is the lower limit. 
Between 75% and 20%, the contactors should rel ease and break completely. In this range, 20 
Us is the upper limit and 75% U s is the lower limit.  
The pick-up limits are determined at  the ambient temperature of +40 ℃ and when coils 
achieve constant temper ature rise under 100% U s. 
The release limits are determined at the ambient temperature of -5 ℃ and when the coil is cold. 
This value can be acquired from the conversion of the value obtained at room temperature. 
The above values are applicable to AV voltage with specified frequency. 
8.2.2 Temperature rise In accordance with the requirements in 8.2.2, 8.2.2.1, 8.2.2.2 and 8.2.2.3, it is applied to clean 
and new contactors. 
When the contactor conducts tests accord ing to the provisions in 9.3.3.3, the allowed 
temperature rise of every part should not exceed the limit value provided in 8.2.2.1, 8.2.2.2 
and Table 6. 
Note: Under normal usage condition, the temperatur e rise might be different from the testing 
value, which is determined by the installa tion condition and the size of the conductors 
connected. 
8.2.2.1 The temperature rise of the terminal The temperature rise of the terminal should not  exceed the limited value provided in Table 4. 
  Table 4 The terminal’s temperature rise limit  
Materials of the terminal Temperature rise limit 
K
a 
Bare copper 60 
Bare brass 65 
Copper (or brass) silver plated 65 
Copper (or brass)or silver or nickel plated   70a GB 17885—200× 
 
 
   Other metals b 
a Terminal’s temperature rise limit (7 0K) is based upon the cable of PVC. 
The external wires used should not be signi ficantly smaller than the wires provided by 
the test (see Table 17), otherwise they w ill cause a big temperature rise of the 
contactor’s terminal and internal parts, wh ich is disadvantageous to the contactors. 
b The temperature rise limit should be based e xperiences or life expectancy test, but it 
should not exceed 65K. 
 
 
8.2.2.2 Temperature rise of the accessible parts  Temperature rise of the accessible parts should not exceed the limits in Table 5. 
  Table 5 Temperature rise limit of the accessible parts 
Accessible part name Temperature rise limit
a 
K 
Parts operated by hand 
Metal 
Non-metal  
15 
25 
Part can be touched but not held 
Metal Non-metal  
30 40 
Parts not touched in the normal 
operations 
Metal 
Non-metal  
40 50 
Parts not touched in the normal 
operations and housing surface near 
the access point of the cable 
Metal Non-metal 40 
50 GB 17885—200× 
 
  The devices with different experime ntal conditions and sizes may be 
provided with different temperature rise  limits, but should not be 10k higher 
than the temperature rise value specified in this cable 
 
8.2.2.3 Ambient air temperature 
The temperature rise limits in Table 4 Table 5 and Table 6 can only be applicable when the 
ambient air temperature remains w ithin the range specified in 7.1.1 
8.2.2.4 Temperature rise of the main circuit 
Conducting tests according to the provisions in  9.3.3.3.4, the contactor’s main circuit should 
be able to withstand the followi ng current without  its temperat ure rise exceeding the limits 
provided in 8.2.2.1: 
—— 8-hour operating time: rated free ai r heating current (see 5.3.2.1 and 5.3.2.2) 
—— Intermittent or short-term operating time: rated operating current (see 5.3.2.3) 
8.2.2.5 Temperature rise of control circuit The control circuit of the cont actors should be under normal operating time specified in 5.3.4. 
When test is conducted as specified in 9.3.3.3.5, th e temperature rise should not exceed the 
limits set in Table 4 and Table 5. 
8.2.2.6. The winding temperature rise of  the solenoid coil and magnet 
8.2.2.6.1 8-hour operating time  
When the current specified in 8.2.2.4 is passing through the main  circuit, the coil winding 
should be able to withstand th e rated control voltage at co ntinuous rated lo ad and rated 
frequency. The temperature rise should not exceed those specified in 8.2.2.2 and Table 6. 
  Table 6 Temperature rise limits of insulating coils in the air 
Heat resistance rating of insulating 
materials Temperature rise limits of insulating coils 
in the air measured by resistance 
K 
A 
E 
B 
F 85 
100 110 135 GB 17885—200× 
 
 
   H 100 
Note 1: The degree 2 in GB/T 11021-2007 is taken as the insulating degree 
Note 2: The temperature rise limits in Ta ble 6 and 8.2.2.2 is only applicable when the 
ambient air temperature remains between -5 ℃~+40 ℃ 
 
8.2.2.6.2 Intermittent operating time 
When there is no current passing the main circ uit and when it is operated by the specified 
intermittent operating time in Table 7, for co il winding under the rated frequency and rated 
control voltage, its temperature rise shoul d not exceed the limits specified in 8.2.2.2 and 
Table 6. 
8.2.2.6.3 Special operating time (short-term and cycle operating time) 
Test with special operating time should be c onducted under the strictest operating conditions 
and its rated value is provided by the manufacturer. 
8.2.2.7 Temperature rise of the auxiliary circuit The contactor’s auxiliary circuit (including auxiliary switch) shoul d be able to withstand the  
free air heating current. When tests are conduc ted according to the provisions in 9.3.3.3.7, the 
temperature rise should not exceed the limits specified in Table 4 and Table 5. 
Note: If the auxiliary circuit is  a part of the contactor, its testing can be conducted together 
with the main circuit, but actual operating current should be applied. 
 
 Table 7 The operating conditions of the intermittent operating time 
The intermittent operating 
time classification Each operating cycle 
s Coil charging time 
1 
3 
12 30 
300 
1200 3600 
1200 
300 120 
12 
3  
 
Select as per load factor. 
 GB 17885—200× 
 
  8.2.2.8 The temperature rise of other parts 
The temperature rise of other parts should not affect their adjacent cu rrent loading parts, 
especially for insulating materials. The factor y should show that they are in accordance with 
the insulating materials heat resistance category (identified by the methods in GB/T 11026.1), 
or as specified in GB/T 11021. 
8.2.3 Dielectric properties 8.2.3.1 General principles a) If the factory has specified the U
imp value (see 5.3.1.3), 8.2.3.2 or 8.2.3.1c), test methods 
are shown in 9.3.3.4.1, 
Note: The requirements of overvoltage categor y II (see appendix F) should be met, unless 
specified otherwise. 
b) If the manufacturer does not specify the U imp value, the provisions in 9.3.3.4.2 should be 
used. 
c) Specified contactors in SELV circuit shoul d be able to withsta nd power frequency test 
voltage of 4000V with an app lication time of 1 min applied on live parts and components of 
any other circuit in SELV circuit. 
d) After the test, check the condi tion of the contactor. Carry out the power frequency voltage 
withstand test for 1 min, as  specified in 9.3.3.5.4b) and 9.3.3.6.2. 
8.2.3.2 Dielectric performance requirements 
a) The following requirements, which are based upon the principles in GB/T 16935.1-1997, 
provide the possibility for th e insulation coordination of the contactors and devices. 
b) Contactors should withstand the dielectric test required in 9.3.3.4.1. 
c) Contactors shall withstand rated impulsive withstand voltage (see 5.3.1.3) corresponding to 
the overvoltage categories specified in the appendix F. 
d) The rated impulsive withstand voltage corr esponding to a specified rated operating voltage 
(see 5.3.1.1 Note 1, 2) , should be no less than th e nominal voltage of the power system the 
contact is in and rated impulsive with stand voltage specified in appendix F. 
8.2.3.2.1 The main circuit of shock pressure a) The creepage between the live parts and groun d and that between the poles should be able 
to withstand the rated impulsive withst and test voltage in Table 18 (see 9.3.3.4.1). 
b) Contactors related solid insu lations in a) shall withstand the impulsive withstand voltage 
specified in a). 
8.2.3.2.2 Impulsive voltage of the auxili ary circuit and control circuit GB 17885—200× 
 
 
   a) Auxiliary circuit and control circuit, which connected direc tly with the main circuit under 
the rated operating voltage , should meet the requirements in 8.2.3.2.1a) and b) . 
b) Auxiliary circuit and control circuit, which ha ve no direct connection w ith the main circuit, 
can be different in its ability to withstand the vo ltage of the main circuit. These circuit (AC or 
DC) and related creepage of solid insulation sh ould be able to withstand the corresponding 
voltage required in Appendix F.  
8.2.3.2.3 Clearance Clearance should enable the contact to withstan d rated impulsive withstand voltage specified 
in 8.2.3.2.1 and 8.2.3.2.2. 
Contactors should adopt the minimum clearance  provided in Table 19, circumstance B (for 
uniform electric field, see 3.5.31) and conduct test s as per 9.3.3.4.1f). If it is more than the 
minimum clearance in Table 19 circumstance A (non-uniform electri c field), it is not 
necessary to conduct the rated im pulsive withstand voltage test. 
Clearance measurements are shown in appendix E. 
8.2.3.2.4 Creepage distance a) Determine the distance For contactors of pollution le vel 3 and 4, although minimum cl earance allowed can be less 
than circumstance A specified in 8.2.3.2.3, in orde r to reduce the disruptive discharge risks, 
creepage distance should be  no less than the circumstance A specified in 8.2.3.2.3. 
The creepage distance measurements are shown in appendix E. Creepage distance should corres pond to the relevant product st andards or the pollution level 
specified in 7.1.3.2, and correspond to the relevant categories of the rated voltage or actual 
operating voltage of insulati on materials in table 20. 
Insultation materials can be di vided into the following four categories according to their CTI 
values: 
Insulation materials group I:  600 ≤CTI 
Insulation materials group II:  400 ≤CTI < 600 
Insulation materials group IIIa:  175 ≤CTI < 400 
Insulation materials group IIIIb: 100 ≤CTI < 175 
Note 1: The value of CTI is obtained by the methods specified in GB/T 4207, for insulation 
materials. GB 17885—200× 
 
  Note 2: Non-organic insulation materials, such  as glass and ceramic,  do not produce electrical 
marks. Creepage distance does not need to be gr eater than relevant cl earance, but disruptive 
discharge must be taken into consideration. 
b) The use of ribs Regardless of the quantity of the ribs, if minimum height is 2m m, then the creepage distance 
can be reduced to 0.8 times of the relevant va lue in Table 20. The minimum width of the ribs 
is determined by mechanical requirement (appendix E E.2) 
Measure to see if they meet the requirements. 8.2.3.2.5 Solid insulation 
The principle to determine the size of th e solid insulation is under consideration. 
8.2.3.2.6 The electric clearance between the separate circuit To determine the electric clearance between the separate circuit, creepage distance and solid 
insulation, the highest rated volta ge should be considered. Use the rated impulsive withstand 
voltage to determine electric clearance and solid insulation, a nd use rated insulating voltage 
or actual operating voltage to determine the creepage distance. 
Use the measurements to determine whether they conform to the requirements. 
8.2.4  
Normal load and overload condi tion performance requirements 
The requirements of the charac teristics of the normal load and overload in 5.3.5 will be 
provided in 8.2.4.1 ，8.2.4.2 and 8.2.4.4 below. 
8.2.4.1 
Making and breaking abilities According to the specifications on testing me thods in 9.3.3.5, contactors should be able to 
make and break current and perform operati ng cycle times according to the relevant 
categories in Table 8. 
The power time and time interval should not  exceed the values in Table 8 and Table 9. 
If the manufacturer agrees, it is allowed to shorten the time inte rval or extend the power time. 
Table 8 : The conditions of making and break ing capabilities for different categories 
The conditions of making and breaking 
Usage 
category Ic/Ie Ur/Ue cosφ power timea time No. of 
operation GB 17885—200× 
 
 
   s interval 
s cycles 
AC-7a 
AC-7b 1.5 
8.0 1.05 
1.05 0.80 
0.45 0.05 
0.05 b 
b 50 
50 
a 0.05s listed in table is the minimum, the maximum power time should not exceed 
0.1s. If the contactor has been completely closed before disconnection, time less than 
0.05s is allowed. 
bSee table 9 
 GB 17885—200× 
 
   
Table 9 The correlation of breaking current and the interval time 
Breaking current I c 
A Interval time 
s 
Ic≤100 
100 ＜ Ic ≤ 200 
200 ＜ Ic ≤ 300 10 
20 30 
 
8.2.4.2 Rated operating performance 
The test relevant to the operation performan ce of the contactors was used to verify the 
capabilities of the device on making, carrying and breaking th e main current without any 
faults. 
According to the provisions of the testing method in 9.3.3.6, contactors should be able to 
make and break the current and perform operati ng cycle times according to the categories in 
Table 10. 
 
Table 10 Conditions of making and breaking capabilities for different categories 
The conditions of making and breaking 
Usage 
category Ic/Ie Ur/Ue cosφ power timea 
s time 
interval 
s cycling 
times 
AC-7a 
AC-7b 1.0 
d 1.05 
c 0.80 
0.45 0.05 
0.05 b 
b 30 000 
30 000 
a 0.05s listed in table is the minimum, the maximum power time should not exceed 
0.1s. If the contactor has been completely closed before disconnection, time less than 
0.05s is allowed; 
b 
See table 9; 
c To making operation Ur/Ue=1.0  to break operation Ur/Ue=0.17; GB 17885—200× 
 
 
   d To making operation Ic/ Ie=6.0 to break operation Ic/ Ie=1.0.  
8.2.4.3 Overload current withstand capacity 
Usage category for AC - 7b contact shall withstand test methods according to the provisions 
in 9.3.5, the current regulations in Table 11. 
Table 11 Overload current withstand requirements 
Test current Power time 
s 
8Iemax (AC-7b) 10 
8.2.5 Short-circuit protection coordination 
Under the condition of the circuit performan ce (rated restrictive short-circuit current) 
For contactors using SCPD as backup protection,  its rated restrictive short-circuit current 
should be tested as specified  in 9.3.4. Specifications are: 
Prospective current Ir, see table 12: 
Table 12 Prospective test current corresponding to rated operating current I r 
Rated current I e 
A Prospective current Ir 
kA 
0 ＜Ie ≤ 16 
16 ＜Ie ≤ 63 1 
3 
a) Rated restrictive short-circuit current I q, only when the current I q is greater than I r, can the 
current I q test be conducted. 
SCPD rated value should be applicable to any given rated current, rated voltage and the 
corresponding rated usage category. 
Test condition will be shown in 9.3.4.2 
Coordination in short circu it conditions: contactor shall not bring harm to people and 
equipment. It is not to be used before being repaired and having parts replaced. GB 17885—200× 
 
  Note: Using SCPD other than that recomme nded by the manufacturer  may invalidate 
coordination. 
8.3 Electromagnetic compatibility 
8.3.1 Immunity Performance of household and similar purpose el ectromechanical contactors in time of 
voltage change should be  as specified in 8.2.1.2. 
Contactor is not sensitive to  the other electromagnetic in terference under th e condition of 
normal use described in 7.1.4 , so it is unn ecessary to conduct the immunity test. 
8.3.2 Emission Household and similar purpose electromechanical contactors do not includ e a circuit, or only 
include simple diode rectifier circuit or components, such as  resistors, or electrical 
components rheostat, (such as wh en using surge suppressor), etc 
The electromagnetic interference only occu rs in the making and breaking operation. The 
electromagnetic interferen ce only lasts for milliseconds. 
Until further research is carried out, the frequency and level are considered to be a part of the 
household and similar purpose electromechan ical contactor normal electromagnetic 
environment. Therefore, there is no n eed for the electromagnetic emission test. 
9 Test 
9.1.1 Overview 
The test should show whether contactors confor m to the requirements of this standard. The 
testing procedures are shown in appendix B. 
9.1.2 Model test 
The model test is used to verify whether the c ontactor's design meets the requirements of this 
standard. 
Experimental test items include the following: a) Temperature rise test (see 9.3.3.3) b) The dielectric pr operties test (see 9.3.3.4) 
c) Rated making and breaking capability test (see 9.3.3.5) 
d) Rated operating performance test (see 9.3.3.6) e) Actuating and actuating sc ope testing (see 9.3.3.1 and 9.3.3.2) 
f) Overload current withst and capacity test (see 9.3.5) GB 17885—200× 
 
 
   g) Performance test under the sh ort circuit cond ition (see 9.3.4) 
h) Terminals of mechanical properties test (see 9.2.4) 
i) Enclosed contactor housing protection degree test (see 9.2.3) 
j) Aging performance test (see 9.2.1.1) 
k) Humidity resistance test (see 9.2.1.2) 
l) Heat resistance test (see 9.2.1.3) m) Abnormal heat resistance and ignition risk test (see 9.2.1.4) n) Rusting resistance test (see 9.2.1.5) o) CTI test (see 9.2.1.6), p) Screws and nut for instal lation and maintenance purpose (not used for terminals) 
performance test (see 9.2.2) 
q) Impact resistance test (see 9.2.5) r) Marking durability test (see 9.2.6) Test procedures using the authentication type group. 
Test procedures, and the quantity and result of the sample are speci fied in appendix B. 
Unless specified otherwise, all tests (or pr ogrammed) should be conducted on the new and 
intact  product. 
Unless specified otherwise, the co ntactor tests are conducted in 25
℃±10℃ ambience air 
temperature. 
9.1.3 Routine testing 
A routine test used to detect defects in material or function, and determine the normal 
function of the contactor. A routine test shoul d be carried out on the contactors one by one 
before the products leave the factory. The test co nditions should be the same or equal to the 
required model testing condition. (see 9.3.6.1) 
The routine test of th e contactors includes: 
—— actuation and actua tion scope (see 9.3.6.2) 
—— dielectric properties (see 9.3.6.3) 
9.1.4 Factory sampling test This standard specifies the validation of the sampling test is the el ectrical clearance test. GB 17885—200× 
 
  Test method (see 9.3.3.4.1f) 
Sampling plan and test procedure are still under consideration. 9.2 Validation requirements The validation of the relevant structural requi rements can be referred to in 8.1, including: 
——materials; 
——contactor structure; ——enclosed device housing protective degree; ——mechanical performance of the terminals; ——the actuator; ——position indicator device (see 3.3.16). 
9.2.1 Materials 
9.2.1.1 Age resistance test 
Contactor elastic components made from rubber,  PVC or similar thermoplastic materials (e.g., 
sealing gasket, film and spiral  cover mat etc), should be test ed in the heating cabinet. The 
atmospheric elements and pressures should be the same as the ambient air in the cabinet, 
having the same natural ventil ation and circulating. Tested components should be suspended 
freely in the cabinet. 
The temperature in the cabinet should be 70
℃±2℃. 
Tested sample should be placed in the heati ng cabinet for 7d (168h). Electric heating is 
recommended for the cabinet. Natural circul ation and ventilation can be achieved through 
aperture on walls. After 7 days, it should be re moved from the heating cabinet and placed in 
the relative humidity of 45% ～55% in room temperature for less than 4 days (96 hours). 
After the test, surface crack or shrinkage should not  appear to have affected its further use, 
nor should it become sticky or greasy. The evaluation method is as follows: 
Using the index finger wrapped with a piece of dry coarse cloth, applying 5N pressure on the 
sample. Indenting marks should show on cloth. Th e testing materials shou ld not stick on the 
cloth. (5N pressure obtained are as follows: test materials will be put on one tray of the scale, 
in another tray the weight put on is equal to the weight  of the testing material plus 500g, then 
use the index finger with a piece of dry cloth to apply pressure to the testing material so as to 
keep the scale in balance). 
9.2.1.2 Damp resistance test GB 17885—200× 
 
 
   The contactor's damp resistance should use th e Cab provided in GB/T 2423.3: constant damp 
heat tests to be carried out. Test conditions are as follows: 
If the contactor has air inlet ap ertures, then they should be op en. If it has knock-off holes, one 
should be open. The parts that can be re moved without tools should go through heat 
resistance test after it has been removed, toge ther with the contactor . The cover should be 
open when conducting the tests. 
The sample should be placed in room temperature no less than 4 hours before putting into the 
test cabinet. Test cycl e is 4 days (96 hours). 
After damp heat tests, the samples should be ta ken out. Installed all parts and put on the cover. 
Then according to the provisions in 9 .3.3.4.2, power frequency test voltage of 2U e with a 
voltage of no less than 1000V should be a pplied between different parts for 1 minute. 
9.2.1.3 Heat resistance tests 9.2.1.3.1 Contactor heat resistance test 
a) The insulation materials, which support a nd fix current loading components, should 
withstand the ball pressure te st at the temperature of 125
℃±2℃. Insulation material parts on 
the housing supporting or fixing gr ound terminal should undertake te st as specified in b). Ball 
pressure test device as shown in Figure 3.The plane of the test components should be placed 
in a horizontal position supported by a steel plate. The thickness of  steel plate should be at 
least 5mm. Using  a steel ball with a diamet er of 5mm, apply 20N vertical force on the 
surface of the test components. The test should be carried out in the heating cabinet at a 
temperature of 125 ℃±2℃. The test should last for 1 hour. 
After the test, remove the ball and submerge in water. It will cool down close to room 
temperature in 10 seconds. 
Then measuring steel ball is lowered into the tracking of the sample, which should not exceed 
2mm. 
If all or part of this test cannot be conduc ted, a sample with a th ickness of at least 2mm 
should be used for the high pressure ball test. 
Note: For components with a thic kness of less than 2mm, several stacked-up layers may  be 
used. 
b) Does not support insulation materials for cu rrent loading parts and ground components 
(even if they are in contact). It should be able  to withstand ball pressu re test in a) with a 
temperature of 70 ℃±2℃ or 40 ℃±2℃ plus maximum temperature rise, the highest 
temperature rise is determined by the actual value. 
c) Before placing the contactor in heating cabin et, it should be deposited in the room 
temperature for no less than 4 hours. GB 17885—200× 
 
  The contactor should be in place for long enough  to achieve thermal equilibrium and for  
not less than 1 hour. The temperat ure in the cabinet should be 100 ℃±2℃. 
Then, the tested sample should be co oled close to room temperature. 
Then a force of no more than 5N should be  applied to the accessible housing surface 
using a test bar (see Figure 10) . The test bar should not touch any of the powered parts of 
the contactor. Also check the markings on th e contactor are still clear and legible.  
9.2.1.3.2 Material heat resistance test Sample thickness of the insulation material shoul d be at least 2mm, and should withstand the 
requirement of the heat resistance test in (9.2.1.3.1 a) and (or) b)  
Note: If reliable data can be  obtained from the insulation ma terial manufacturer or other 
reliable sources, which can prove that the insu lation materials meet th e above requirements of 
the heat resistance, then the test can be omitted. 
9.2.1.4 Abnormal heat resistance and ignition risk test 
9.2.1.4.1 Contactor component test The validation of the abnormal heat resistance ig nition risk test is the thermal effect produced 
by simulating heat source or glow wire. The gl ow wire test is conducted according to the 
provisions of GB/T 5169.10 and GB/T 5169.11 under the following conditions: 
a) The insulating material components, which s upport or fix the loading parts, should adopt 
the glow wire top end temperature of 850
℃. When conducting tests, ground conductor 
protection is not regarded as the current load ing component. 
b)The insulating material components, which do not support or fix the loading parts and 
ground components (even in contact), should adop t the glow wire top end temperature of 
650℃. 
9.2.1.4.2 Material test 
Perform the following material sample test: Note: If reliable data can be  obtained from the insulation ma terial manufacturer or other 
reliable sources, which can prove that the in sulation materials meet  the requirements of 
8.1.1.4, then the test can be omitted. 
a) Inflammable classification of GB/T test, 11020 b) HWI test (see appendix G). 9.2.1.5 Rusting resistance tests GB 17885—200× 
 
 
   First, the tested black metal components shoul d be submerged in cooling chemical agents 
(such as pure gasoline). Stir the diachronic for 10min to remove all oil stains. Then immerge 
the test components into 10% of ammonium chloride soluti on for 10 minutes. The solution 
temperature should be  controlled at 20 ℃±5℃). Get rid of  excess water drops on parts 
(without drying). Place in the steam-fille d container at a temperature of 20 ℃±5℃ for another 
10 minutes. Then place in the heating cabinet at the temperature of 100 ℃± 5℃ for 10 
minutes to dry. The surface should be free of rust. Rusty spots at the top and yellow rusty 
spots can be ignored. 
For small springs and similar components and parts which are difficult to access, grease 
coating can be used to prevent corrosion. Only when the protective effect is in doubt should 
the test to be performed on them. There is no need to remove the grease stain on the surface 
before the test. 
9.2.1.6 Compared to the index (elect ric mark determination  CTI) 
The test uses the regulation in GB/T 4207 to me asure the insulation material’s CTI value and 
materials group. 
The right parts may be removed from the contac tor or conducted on the right materials with 
permission. 
9.2.2 Screws and nut for installation and main tenance purpose (not used for terminals) 
performance test  
Screw and nut should be tighten ed and loosened as below: 
—— For use with insulating materials, screw th read and nut are tightened and loosened for 
10 times. 
—— For all other conditions, 5 times. For use with insulating materials,  the bolts and nuts should be screwed completely each time. 
Appropriate screwdrivers and to rque wrench should be used, according to the regulation in 
Table 13 or manufacturer. Bolt and nut should not be over-tightened. 
For hexagonal slot bolts tightened with screwdri vers, when the torque values listed in column 
II and III are different, testing should be car ried out twice. The steps are as follows:  
—— Use a wrench to apply the torque specified in column III  
—— Use a screwdriver to apply the torque specified in column II on new samples  
If the value in column II is same to the value in column III, only the test using a screwdriver 
is needed. GB 17885—200× 
 
  In the test, the screw should not get loose, nor should there be damage that might prevent the 
contactor functioning, such as damage to the sc rew, the slot, threaded screw head gasket, 
stirrup or damages to the housing and cover. 
9.2.3 Enclosed contactor housing protection degree test Relevant test procedures  are shown in GB 1408.1-2006. 
After protection degree II test has been carried out, 2U
e test with a voltage  of no less than 
1000V applied for 1 minute should be carried out as specified in 9.3.3.4.2.  
9.2.4 Terminals of mechanical properties test The following test is not applicable for alumin ium terminals and terminals connected to the 
aluminium conductors. 
9.2.4.1 The general conditions of the test Unless specified otherwise, every test should be  carried out on new and intact terminals. 
When round copper wire is used to conduct te sting, it should be in accordance with IEC 
60028. 
9.2.4.2 Terminals mechanical strength test The appropriate type of maximum cross-sectiona l area of conductor should be adopted for the 
tests. Each conductor should be connected and removed 5 times. For screw-type terminals, 
tightening torque should be 110% of the to rque value provided Table 13 or as per 
manufacturer’s specification (w hichever is greater) for test. 
This test should performed on two terminals. For hexagonal head screws tightened with screwd rivers, if the values in the column  II and III 
in Table 13 are different, the test  should be carried out twice. 
Use the torque value in column III for the first te st and then use the torque value in column II 
for the second test. 
If the values in the column II and III are the same, then only the screwdriver test is needed. 
A new conductor should be used each time the bolt or nut is loosened. 
In the test, the screw should not get loose, nor should there be damage that might prevent the 
contactor functioning, such as damage to the sc rew, the slot, threaded screw head gasket, 
stirrup or damages to the housing and cover. 
9.2.4.3 Conductor test for accidental loos ening or damage (bending test) 
This applies to prefabricated round copper wire terminals. Fact ory should specify the number 
of wires, sectional area and type (soft lines and/or hard line, thr ead and/or single core) GB 17885—200× 
 
 
   Use 2 new terminals to perform the test below: 
a) with minimum cross-section wire and th e maximum number of connections allowed 
attached to  terminals for the test 
b) with the maximum cross-section wire a nd the maximum number of connections allowed 
attached to terminals for the test 
c) with provisions of the maximum and mi nimum cross-section wire and the maximum 
number of connections allowed attached to terminals for the test 
For terminals that can be connect ed with both soft and hard wi re (single core and/or more 
thread), tests should performed on di fferent groups of test samples. 
For terminals that can be connect ed with both soft and hard lines at the same time (single 
core and/or more thread), tests should performed as specifi ed in c) above. 
 
Table 13 The tightening torque for screw-type terminal for the mechanical strength test  
Threads diameter, Φmm Torque N·m 
Standard 
values in 
metrics Diameter range Ia IIb IIIc 
2.5  
3.0  
-  
3.5  
4.0  
4.5  
5.0  
6.0  8.0  
10       Φ ≤2.8  
2.8 < Φ≤3.0  
3.0 < Φ≤3.2  
3.2 < Φ≤3.6  
3.6 < Φ≤4.1  
4.1 < Φ≤4.7  
4.7 < Φ≤5.3  
5.3 < Φ≤6.0  
6.0 < Φ≤8.0  
8.0 < Φ≤10.0 0.2 
0.25 
0.3 0.4 0.7 0.8 0.8 
1.2 
2.5 
- 0.4 
0.5 0.6 0.8 1.2 1.8 2.0 
2.5 
3.5 4.0 0.4 
0.5 0.6 0.8 1.2 1.8 2.0 
3.0 
6.0 
10.0 GB 17885—200× 
 
  a Applicable to screw he ads not extruding the hole  (countersunk head) after 
tightening, and can’t be tightened by screwdriver due to the size  
b Applicable to bolts and nuts tightened with a screwdriver. 
c Applicable to bolts and nut tightened by a tool other than a screwdriver. 
The test should be conducted on the appropriate  test device. Connect the required number of 
the wires to the terminals. The length of test wire should be l onger than the height specified 
in the Table 14 by 75mm. The tightening torque  should be as specifi ed in Table 13. Test 
equipments are as shown in Figure 4. 
Each wire is under circular motion accord ing to the following test procedures: 
The end of wire should go through the hole busher on the binder plate. The plate is set at 
position H (see Table 14). Bend all other wires so th at they will not get in the way of the test. 
Bushings should be installed together with wire , horizontally position on the plate. Bushings 
with a speed of 10 (r.p.m) ±2 (r.p.m) draw a ci rcle with a diameter of 75mm on the surface 
around the linking piece. The dist ance between the terminal ou tlet and the surface of the 
bushing is height (H), with a to lerance of 13mm. Lubrication shoul d be applied to bushings in 
order to prevent the insulation wire from be nding, twisting or rotati ng. The mass provided in 
Table 14 should be applied to the end of the wires, while the te st should continue rotating for 
135 circles. 
During testing, the wires should not emerge fr om the terminals nor be broken near the 
clamping point. 
After bending test, wires used in the test s hould undergo a pull-out te st as specified in 9.2.4.4. 
Table 14 Test values of the round copper wire bending test and the pull–out test  
Wire section 
mm Bushing 
aperturea 
mm Height H±13 
mm Quality 
kg Tension 
N 
0.2 
- 6.4 
6.4 260 
260 0.3 
0.3 10 
20 
0.5 
0.75 6.4 
6.4 260 
260 0.3 
0.4 30 
30 
1.0 1.5 6.4 
6.4 260 
260 0.4 
0.4 35 
40 GB 17885—200× 
 
 
   2.5 
4.0 9.5 
9.5 279 
279 0.7 
0.9 50 
60 
6.0 
10 9.5 
9.5 279 
279 1.4 
2.0 80 
90 
16 25 12.7 
12.7 298 
298 2.9 
4.5 100 
135 
- 
35 14.3 
14.3 318 
318 5.9 
6.8 156 
190 
aIf it’s difficult for the hole (diameter specified in the table) to accommodate the wire, 
the next available larger apertu re in the table can be used. 
 
9.2.4.4 Round copper wire pull-out test After the bending test in 9.2.4.3, then the tensio n provided in Table 14 should be applied to 
the bending test's wires in 9.2.4.3.  
Wire clamping screw in the test should not be tightened again. Tension should be maintained 
for 1 minute. Tension should be applied gradually. 
Wires should not get loose from the terminals during the test, or br eak  while they are 
clamped. 
9.2.4.5 Round copper wire of maximum cr oss-section access capability test 
9.2.4.5.1 Test procedures Table 15 provides the analogue gauge for the te st. The cross-section of the gauge should be 
able to pass through the holes on the terminals and the gauge shoul d be able to set  into the 
terminals completely by its own weight (see note in table 15). 
  Table 15 Biggest wire s ection and corresponding gauges 
Cross-sectional area Analogue gauge (see Figure 5) 
Soft wire 
 
mm Hard wire 
(Single or 
multiple 
thread) 
mm Model no. 
 Diameters 
a 
mm Width 
b 
mm Tolerance 
of a and b 
mm GB 17885—200× 
 
  1.5 1.5 A1 2.4 1.5 
2.5 2.5 A2 2.8 2.2 
2.5 4 A3 2.8 2.4 0 
-0.05 
4 6 A4 3.6 3.1 
6 10 A5 4.3 4.0 
10 16 B6 5.3 - 0 
-0.06 
16 25 B7 6.9 - 
25 35 B8 8.7 - 
35 50 B9 10.0 - 0 
-0.07 
Note: If the wire section is as specifie d in the table, round copper wire with 
appropriate section value can be used as the analogue gauge, inserting force should be 
no more than 5N. 
 
9.2.4.5.2 Gauge structure 
Gauge structure as shown in Figure 5 Size a and size b and Tolerance are shown in Table 15. Gauge measurement part should be 
made of gauge steel. 
9.2.5 Impact resistance test 9.2.5.1 Procedure test Exposed components of the open and semi-enclose d contactors, cover and cover plate of the 
contactors should be tested on the pendulum test equipment with impact energy of 0.5J. 
The housing of the enclosed contactor should be  tested with spherical test equipment (see 
9.2.5.2.2) with impact energy of 2J. 
Ambient air temperature is 25
 ℃ ±10  ℃. 
Samples with cover and housing should be inst alled in accordance with the normal conditions 
of use, or should be attached next to the stee l rack. The cable inlets should be open. If the 
cable inlets use knock-off holes, th en two of them should be open. 
Before the impact, base, cover and similar fasten ers should adopt 2 / 3 of the torque in Table 
13 to conduct the tightening. GB 17885—200× 
 
 
   The sample should be subject to the impact 10 times, and the point of impact should be 
evenly distributed. 
The impact should not fall on the knock-off hole area or fragile components (such as 
observation windows, i ndicators, etc.)  
5 of the impacts should be conducted as follows: a) For an embedded contactor, one impact falls on the centre and then one on each end of the 
installation slot. The other two impacts should fa ll on the midway of the previous two points 
of impact, best to be on the lateral edges. 
b) For other types of contactor s and install cabinets, one impact falls on the centre and then 
rotate the sample horizontally (c lose to but not more than 60º)  and the impact falls to each 
side of the sample. The other two impacts s hould fall on the midway of the previous two 
points of impact, best to be on the lateral edges. The other two impacts are conducted the 
same way after rotating the sample 90º vertically. 
After the test, the sample should not have any damage that will affect its further use. In 
particular, the cover should not be damaged leaving live parts are accessible. And there 
should be no damage that will affect the normal use of contactors, actuators and insulation 
pads or dividers. In case of doubt, external  components such as housing and cover can be 
removed for inspection (but thes e components or the insulation pads should not be damaged).  
Any cracks on the surface that will not reduc e the creepage or clearance to below the 
specifications in Table 8.1.3, small dents or  damages that have no obviously effects on 
electric shock protec tion can be ignored. 
9.2.5.2 Test equipment 9.2.5.2.1 Pendulum test equipment (0.5J test) Test equipments are shown as in Figure 6, Figure 7 and Figure 8. Test equipments should be able to move the sa mple horizontally and ro tate it along the axis 
perpendicular to the laminate and the vertical  axis of the laminate  can rotate along the 
perpendicularly axis. 
The mass of impact components is 0.25kg. It sh ould fall from the height of 0.20 m onto the 
exposed surface of the contactor installed as per normal usage, and the impact point should 
fall on the plane perpendicular to the pendulum. 
The drop height should be the vertical distance be tween the testing point at the release of the 
pendulum and impact point. The testing point sh ould be marked on the surface of the impact 
component. 
The head of the impact component should have  a semi-spherical surface with a radius of 
10mm, which is made from polyamide materi al. The surface hardness is Rockwell hardness GB 17885—200× 
 
  R100. Impact component was fixed under a steel pi pe which has an external diameter of 9 
mm, a wall thickness of 0.5 mm. The top of the pipe  is fixed with a hinge so that it can only 
swing within a vertical plane. 
The axis of the hinge should be 1000mm ±1 mm on top of the axis of the impact components 
To determine the polyamide Rockwell hardness of  the head of the impact components, the 
following should be adopted: 
──Diameter of the ball: 12.7 mm ± 0.002 5mm ； 
──Starting load: 100N ± 2N; 
──Overload: 500N ± 2.5N. 
For details, see ISO 2039-2. The plane-installed c ontactors should be installed on a laminate 
of 8mm thick, 175mmin size. The laminated shoul d be fixed on a steel rack, which is also 
part of the installation rack (see Figure 7).The  mass of the rack is 10kg ±1kg. It is installed on 
a steel frame with a pivot. 9.2.5.2 .2 Ball test equipment (2J Test) As shown in Figure 9, the impact is produced by the drop or the swing of the ball. The steel ball has a diameter of 50mm and a weight of 0.5k g and is released from  a height of 0.4 m. 
Height (H) is the vertical distance. When the cycl oid is in vertical positi on, the steel ball is in 
contact with the test sample. The mass of the cycloid can be ignored when compared to the 
steel ball. The support should be on e layer of oak board with two layers of laminates. The oak 
board has a thickness of about 19mm. The joint board should be placed on a concrete floor. 
Nonelastic supports of the same  effect can also be used. 
9.2.6 Marking durability test To test if the marking is as  specified in 8.1.12, rub it with a wet cloth for 15 seconds, then 
with a gasoline-absorbent cloth for another 15 se conds. The gasoline used in the test is made 
from aliphatic hexane solution. The maximum vo lume ratio of aromatic series should be no 
more than 0.1%. The kauri buranol value is 29. The boiling point is 65
℃, drying point is  
69℃ and the specific gravity is 0.68g/cm3. 
After the test, the markings should be easy to  identify. The nameplate should not move or 
warp. The markings should still be easy to read after all tests in the standard  have been conducted. 
Markings made from stamping, mould pressing, ramming or carv ing do not need to undertake 
this test. 9.3 Verifying the performance requirements 9.3.1 Procedure test Procedure test and test sample see Appendix B. Sample should be able to withstand the 
procedure test. 9.3.1 General conditions of the test 9.3.2.1 General requirements All data of the contactors tested should be th e same as in the figures  and technical documents. 
Unless specified otherwise, the current type, frequency under AC conditions and phase of the 
test should be the same as expected. If stricter test data have been adopted to facilitate the test, GB 17885—200× 
 
 
   eg. higher frequency has been adopted to reduce th e test cycle, this must be agreed by the 
manufacturer. Contactors tested should be inst alled on the rack or supports of similar effects as specified in 
the manufacturer’s manual. Wiring should be done as per normal use. Environmental conditions for installation location should be as specified in 7.1. Enclosed contactors should be installed prope rly. Apertures closed in normal operation 
should be closed as well during the test. Enclos ed contactor in single housing should be tested 
in the smallest housing as specified by the manufacturer.  Note: Single housing is designed to be used by only one contactor. 
Otherwise, contactors should be tested in the atmosphere. Unless specified otherwise, when 
conducting making and breaking te st and performance test unde r short-circuit conditions, 
metal mesh should be placed around the contactors at the possible yield points, as specified 
by the manufacturer. The distance between the contactor and the mesh should be noted in the 
rest report.  Unless specified otherwise, repair an d part replacement are not allowed. 
Prior to the test, contactors can be operated empty-loaded a few times. 
Unless specified otherwise in the standard, the operating sy stem should be operated under 
expected usage conditions usi ng the rated control parameters  (eg. rated cont rol voltage). 
9.3.2.2 Test parameters 9.3.2.2.1 Test parameter value All tests should be conducted using the data pr ovided in the standard  and as per the rated 
parameters of manufact urer’s specifications. 
9.3.2.2.2 Tolerance of the test parameters Unless specified otherwise in th e standard, tolerance in the te st should be as specified in 
Table 16. If agreed by manufacturer, the test  can be conducted in stricter conditions. 
Table 16 Tolerance of test parameter 
All tests Tests under empty load, 
normal load & overload 
conditions Tests under short-circuit 
conditions 
Current: 0+5% 
   Voltage: 0+5% Power factor: ±0.05 
Frequency: ±5% Power factor: 0 -5% 
Frequency: ±5% 
Note 1: Specifications in table ar e not applicable to operating range. 
Note 2: As agreed by manufacturer and user, test conducted under 50 Hz can be 
considered as applicable to under 60 Hz conditions, vice versa. 
 
9.3.2.2.3 Recovery voltage 
a) Power frequency recovery voltage 
For all breaking and short-circu it breaking capabilities test, power frequency recovery voltage 
should be 1.05 times of the rated operating voltage. Note 1: The power frequency recovery voltage  is 1.05 times of the rated operating voltage. 
This has taken into consideration of the fluctuation of the power system voltage. 
Note 2: The applied voltage can be increas ed in the breaking test. However, without 
manufacture’s agreement, the predictive peak  making current should not exceed the specified 
value. Note 3: If agreed by the manu facturer, the upper limit of power  frequency recovery voltage 
can be increased (see 9.3.2.2.2).  b) Transient recovery voltage Requirements see 9.3.3.5.3. 9.3.2.3 Test result evaluation GB 17885—200× 
 
  For contactor’s operating condi tions and after-test conditions , see relevant parts in the 
standard. 9.3.2.4 Test report The manufacturer should provide  appropriate documents to show the contactors are in 
compliance with the standard. Test details, e.g. housing, size, wire size, distance between live  parts and housing or distance 
to parts connected to ground under normal opera ting conditions and operating system etc, 
should be listed in the test report. Test value and parameters are listed in details in the test report.  9.3.3 Performance test under empty load, normal load & overload conditions 9.3.3.1 Actuating conditions Conduct test as specified in 8.2.1.1 9.3.3.2 Actuating range Actuating range should be verified as meeting the requirements in 8.2.1.2. 
9.3.3.3 Temperature rise test 9.3.3.3.1 Ambient air temperature At least two temperature gauges (eg. thermometer or thermoelectric couple) should be used to 
test the ambient air temperature and the ga uges should be evenly distributed along the 
contactors, at half of the height of the contactor and 1 metre away from it. Make 
measurements and recordings at the last ¼ cy cle of the test. The temperature gauge should 
not be affected by the current, heat radiation and r eading errors from the sudden change of 
temperature.  
During the test, the ambient air te mperature should be within +10 ℃～＋ 40℃, and its change 
should not be over 10K.  
9.3.3.3.2 Appropriate temperature ga uge should be used. Measurem ent points are those at the 
highest temperature rise. Measurement point s should be noted in the test report. 
The temperature gauge should not have  obvious impact on temperature rise. 
Good heat exchange should be maintained betw een the temperature gauge and the test sample 
surface. Resistance methods are normally used for measuri ng the coil temperature. Only when this is 
difficult, other methods are considered. The difference in temperature between the co il and the surrounding medium should be no 
more than 3K. 
The hot-state temperature of the coil T
2 can be calculated by cold-state temperature T 1, hot-
state resistance R 2 and cold-state resistance R 1 from the formula below:  
 
where, 
T1,T2－temperature, ℃ 
R1,R2－resistance, Ω . 
T2 is the when the constant temperature rise has been achieved (charging time no more than 8 
hours); When the temperature rise is less than  1K per hour, it is considered constant 
temperature rise has been achieved. 9.3.3.3.3 Temperature rise of parts GB 17885—200× 
 
 
   Temperature rise of parts is the temperat ure difference between the part temperature 
measured as specified in 9.3.3.3.2 and the ambien ce temperature measured as specified in 
9.3.3.3.1.  9.3.3.3.4 Temperature rise test  of the main circuit 
Contactors should be installed as per 9.3.2.1, and should not be a ffected by external abnormal 
heating and cooling.  Main circuit should undertake load as specified in 8.2.2.4. 
Generally, the auxiliary circuits  should apply the maximum ra ted operating current (see 5.6). 
Rated voltage should be applied to the control circuit. For co ntactors with housing, rated free-
air heating current should be applied, and abnormal vents on the housing are not allowed.  
Contactors that can be used in different types of housings should be tested in the smallest 
housing as specified by the manuf acturer or tested without hous ing. If tested without housing, 
manufacturer should provide a rated encl osed heating current  value (see 5.3.2.2). 
For multi-phase current test, the current for each phase should be balanced with a tolerance of 
±5%, and the average value should not be less than the test current specifies. 
Unless specified otherwise, the temperature rise  test of the main ci rcuit should be conducted 
under one or all rated free-air heatin g currents as per 5.3.2.1 and 5.3.2.2, and under any 
voltage.  When the heating and the temperature rise be tween the main circuit, control circuit and 
auxiliary circuit affect each other, the temper ature rise tests for thes e circuits should be 
conducted at the same time as per 9.3.3.3.4 ～9.3.3.3.7. 
If agreed by the manufacturer,  multi-pole contactors should us e parallel connec tion to apply 
single-phase current to conduct test. After the test, the temperature ri se of all parts in the main ci rcuit should not exceed the values 
in Table 4 and 5. The wires should be selected as follows: 
a) The wires should adopt PVC insulating copper wire, with a cross-section as specified 
in Table 17, or smaller if  agreed by manufacturer. 
b) Wires should be placed in atmosphere, dist ance between wires is the distance between 
terminals. 
c) When conducting single-phase or multi-phase temperature rise te sts, the distance 
between terminals, or terminal to power s upply or to star conn ecting point should be 
no less than 1 metre 
9.3.3.3.5 Temperature rise test of the control circuit 
Temperature rise test of the c ontrol circuit should be conducted at  the same time as the test in 
9.3.3.3.4.  
Temperature rise test of the control circuit should adopt rated current, frequency and voltage. 
Temperature rise test of the control circuit s hould be carried on until a constant temperature 
rise is achieved. 
After the test, the temperature rise of all parts in the cont rol circuit should not exceed the 
values in 8.2.2.5.  
 GB 17885—200× 
 
   
 
Table 17 Copper leads for temperature rise tests 
Lead section Test current range (I) 
A mm2 AWG/MCM 
0< I≤8 
8<I≤12 
12< I≤15 
15< I≤20 
20< I≤25 
25< I≤32 
32< I≤50 
50< I≤65 
65< I≤85 
 1.0 
1.5 2.5 2.5 4.0 6.0 
10 16 25 
 18 
16 14 12 10 10 
8 6 4 
 
Note 1: To facilitate test, conductors with lower test current can be used if agreed by 
manufacture. Note 2: Conduct size in metric measurement is  listed in the table,  together with the 
AWG/MCM change. 
 
9.3.3.3.6 Temperature rise of electromagnetic coil Electromagnetic coils should be tested according to 8.2.2.6. 
Test should be carried on until a constant te mperature rise has been achieved. Temperature 
rise should be measured when the main ci rcuit and the electroma gnetic coil have both 
achieved thermal equilibrium. Electromagnetic coils of the contact ors should be tested as follows: 
a）For contactors to be used for 8 hours, onl y the test specified in 8.2.2.6.1 should be 
performed on its electromagnetic coils. The appr opriate rated current will be applied in the 
main circuit in the test and the te mperature rise is tested in 9.3.3.3.4. 
b）For contactors used in intermittent cycles , corresponding test specified in 8.2.2.6.2 should 
be performed on its electromagnetic coils. The main circuit is not powered in the test. 
c）For contacts used for special purpose (temporaril y or in intermittent cycles), test specified 
in 8.2.2.6.3 should be performed on its electromagnetic  coils. The main circuit is not powered 
in the test. After the test, temperature rise  for all parts should not exceed  the value specified in 8.2.2.6. 
9.3.3.3.7 Temperature rise of auxiliary circuit The temperature rise test for auxiliary circ uit should be performed in test 9.3.3.3.4. Test 
conditions are as specified in 9.3.3.3.5; howev er, they can be tested in any voltage. 
After the test, temperature rise  for all parts should not exceed  the value specified in 8.2.2.7. 
9.3.3.4 Dielectric characteristics Tests should be performed as follows: 
a） If rated impulse withstand voltage U
imp  (see 5.3.1.3) is specified by the manufacturer, 
the test is performed as specified in 9.3.3.4.1. GB 17885—200× 
 
 
   b） If rated impulse withstand voltage U imp  is not specified by manufacturer, test is 
performed as specified in 9.3.3.4.2. 
Under such circumstances, clearance and cr eepage distance are verified according to 
measurement methods (see Appendix E). 9.3.3.4.1 Dielectric characteristic test for impulse voltage 
a）General conditions 
Contactors tested should m eet the requirements in 9.3.2.1. If the contactors do not have 
housing, they should be placed on a metal plate with all exposed conductive parts (frames etc) 
to ground connected to the metal plate. If th e contactors do not have a housing, insulated 
material actuators and non-metal housing should be wrapped in foil, and connected to the 
frame or the installation metal plate. Foil shoul d cover all areas in contact with the test 
samples (see Figure 10). 
b）Verify the impulse withstand voltage (cl earance and corresponding so lid insulators)   
Contactors should meet the requirements of 8.2.3.1 and 8.2.3.2. 
 Rated impulse withstand voltage test (see Figure 18) is used to verify the clearance of the 
contactors and the dielectric characteristics of the solid insulators. When clearance is greater than or equals to th e specification in instance A in Table 19, it can 
be verified using the measurement method in Appendix E, with no need for the impulsive 
withstand voltage test. Disruptive discharge such as puncture  or flashover should not occur. 
Note 1: Intentional disruptive discharge is an  exception, for instance,  transient overvoltage 
restrictive measures. Note 2: Disruptive discharge is related to in sulator fault under the electric stress tensor. 
Under this circumstance, discharge will short circuit the insulator being tested and reduce the voltage to zero or near zero. Note 3: Sparkover is used when disruptive discharge happens in gas or liquid matter. 
Note 4: Flashover is used when disruptive disc harge happens in the surface of gas or liquid 
matter. Note 5: Puncture is used when disrup tive discharge happens through solid matter. 
Note 6: Disruptive discharge will make solid matter lose its dielectric strength permanently, 
while just temporarily for gas or liquid matter. 
c）Test voltage 
The voltage in the impact test s hould be as specified in 8.2.3.1 and 8.2.3.2. 
 Test voltage energy should not exceed the specification for overvoltage suppressor (if 
applicable).  Note: The rated value of voltage suppressor must be suitable for use, which is under 
consideration. Apply 1.2/50µs positive and negative impulsive w ithstand voltage for three times each, with 
a gap of at least 1 second. 
 
Table 18 Impulsive withstand voltage and altitude correction value 
U1.2/50 Impulsive voltage 
 
kV 
Impulsive 
withstand 
voltage 
Uimp 
kV Sea level 200m 500m 1 000m 2 000m 
0.33 
0.5 0.36 
0.54 0.36 
0.54 0.35 
0.53 0.34 
0.52 0.33 
0.5 GB 17885—200× 
 
  0.8 
1.5 2.5 
4 6 8 
12 0.95 
1.8 2.9 4.9 7.4 9.8 
14.8 0.9 
1.7 2.8 4.8 7.2 9.6 
14.5 0.9 
1.7 2.8 4.7 
7 
9.3 
14 0.85 
1.6 2.7 4.4 6.7 
9 
13.3 0.8 
1.5 2.5 
4 6 8 
12 
 
d）Application of test voltage  
Contactors tested should be installed and prep ared according to the specification in a), with 
the voltage applied at: 1) Contacts are at the normal working locations. Terminals on the main circuit are connected 
between housing and installation plate. 2) Contacts are at the normal working locations. Each pole on the main circuit is connected 
between housing and installation plate. 3) Normally not connected between the control ci rcuits and the auxiliary circuits of the main 
circuit and the following parts: ──main circuit 
──other circuits 
──exposed conductive parts 
──housing or installation plate 
Parts above can be connected as appropriate. e) Verification of creepage Minimum creepage of the contac tors between phases, conductors from different voltage 
circuits, and between electrical  conductors and exposed conduc tors should be measured and 
should meet the requirements in 8.2.3.2.4. f) Sampling test for creepa ge distance verification 
Sampling test is for verification of contactors (creepage distance less than the value specified 
in Table 19, instance a) meeting the design requ irements. Test voltage corresponds to rated 
impulsive withstand voltage. GB 17885—200× 
 
 
    
Table 19 Minimum creepage distance in air 
Min. creepage 
mm 
Instance A 
Uneven electric field (see 3.5.32) Instance B 
Even electric field (see 3.5.31) 
Pollution degree Pollution degree Impulsive withstand 
voltage 
Uimp 
kV 
1 2 3 4 1 2 3 4 
0.33 0.01 0.01 
0.5 0.04 0.04 
0.8 0.1 0.2 
0.1 0.2 
1.5 0.5 0.5 0.8 
0.3 0.3 
2.5 1.5 1.5 1.5 1.6 
0.6 0.6 0.8 
4 3 3 3 3 1.2 1.2 1.2 1.6 
6 5.5 5.5 5.5 5.5 2 2 2 2 
8 8 8 8 8 3 3 3 3 
12 14 14 14 14 4.5 4.5 4.5 4.5 
Note: Minimum creepage distan ce in air is based on 1.2 /50 µs impulsive voltage. Air 
pressure is 80kPa, equal to normal air pressure at 2,000m altitude. 
 
Sampling test scheme and pro cedures are in consideration. 
Voltage should be applied as per specification in  d), but foil does not need to be attached 
outside of actuator and housing. Disruptive discharge should not occur during the test. 
9.3.3.4.2 Dielectric characteristic test  for power frequency voltage 
a）Conditions for tested contactors 
The dielectric characteristic te st should be performed on properly  installed (inc luding internal 
wiring), clean and dry contactors.   If contactors use an insulated base, the metal parts should be tightened appropriately and be 
considered as part of the contactor frame. When the contactors are installed inside the 
insulated housing, the housing should be wrappe d in foil and corrected to the frame. If the 
dielectric strength is related to the special in sulator of the lead tap, the same lead tap or 
special insulator should be used in the test. 
b）Application of the test voltage 
If motor, meter, snap switch and semi-conduc tor devices have been installed, plus the 
withstand dielectric test voltage  is less than the specification in c), they should be removed 
for the test as per the manufacturer’s instructions. 1) Power frequency withsta nd voltage for main circuit 
Connect the control circ uits (which are not normally connect ed to the main circuits and the 
auxiliary circuits) to the ma in circuit. Time: 1 minute. 
When main contact is closed: ——between all terminals connected together and contactor frames 
——each pole and all poles connected to the frame When main contact is open: 
——between all terminals connected together and contactor frames 
——between all incoming-line terminals and outgoing-line  terminals connected  GB 17885—200× 
 
   
Table 20 Min. Creepage 
Creepage distance of contactor s under prolonged voltage 
mm 
Pollution degree Pollution degree Pollution degree Pollution degree 
1 f 2 f 1 2 3 4 
Material category Material category a Material category Material category Rated 
insulated 
voltage or 
actual 
operating 
voltage of 
contactors 
(r.m.s) 
Ve b c b I II IIIa IIIb I II IIIa IIIb I II IIIa IIIb
10 
12.5 
16 20 25 32 40 50 63 80 
100 125 160 200 250 320 400 500 630 
 0.025 
0.025 0.025 0.025 0.025 0.025 0.025 0.025 
0.04 
0.063 
0.1 
0.16 0.25 
0.4 
0.56 0.75 
1 
1.3 1.8 0.04 
0.04 0.04 0.04 0.04 0.04 0.04 0.04 
0.063 
0.1 
0.16 0.25 
0.4 
0.63 
1 
1.6 
2 
2.5 3.2 0.08 
0.09 
0.1 
0.11 
0.125 
0.14 0.16 0.18 
0.2 
0.22 0.25 0.28 0.32 0.42 0.56 0.75 
1 
1.3 1.8 0.4 
0.42 0.45 0.48 
0.5 
0.53 0.56 
0.6 
0.63 0.67 0.71 0.75 
0.8 
1 
1.25 
1.6 
2 
2.5 3.2 0.4 
0.420.450.48
0.5 
0.53
0.8 
0.85
0.9 
0.95
1 
1.05
1.1 1.4 1.8 2.2 2.8 3.6 4.5 0.4 
0.42 0.45 0.48 
0.5 
0.53 
1.1 1.2 
1.25 
1.3 1.4 1.5 1.6 
2 
2.5 3.2 
4 5 
6.3 1 
1.05
1.1 1.2 
1.25
1.3 1.4 1.5 1.6 1.7 1.8 1.9 
2 
2.5 3.2 
4 5 
6.3 
8 1 
1.05
1.1 1.2 
1.25
1.3 1.6 1.7 1.8 1.9 
2 
2.1 2.2 2.8 3.6 4.5 5.6 7.1 
9 1 
1.05 
1.1 1.2 
1.25 
1.3 1.8 1.9 
2 
2.1 2.2 2.4 2.5 3.2 
4 5 
6.3 8.0 
10 1.6 
1.6 1.6 1.6 1.7 1.8 1.9 
2 
2.1 2.2 2.4 2.5 3.2 
4 5 
6.3 
8 
10 
12.5 1.6 
1.6 1.6 1.6 1.7 1.8 2.4 2.5 2.6 2.8 3.0 3.2 
4 5 
6.3 
8 
10 
12.5
16 1.6 
1.6 1.6 1.6 1.7 1.8 
3 
3.2 3.4 3.6 3.8 
4 5 
6.3 
8 
10 
12.5
16 20 d 
 
a According to GB/T 16935.1, trackin g is unlikely to occur here; 
b  Material category I, II, IIIa, IIIb; 
c  Material category I, II, IIIa ； 
d  Creepage distance of the area is not identified yet, material category IIIb is generally not recommended for 
pollution degree 4; 
e  As an exception, the creepage distance of ra ted insulated voltage 127V, 208V, 415/440V, 660/690V can 
adopt the creepage distance of  relatively lower voltage  of 125V, 200V, 400V, 630V; 
f  Creepage distance of print circuit materials can adopt th e values in these two columns. 
 
 
2) Power frequency withstand voltage test fo r control circuits a nd auxiliary circuits 
Normally the control circuits and auxiliary circu its connected to the main circuits are tested 
together with the main circuits. GB 17885—200× 
 
 
   For the control circuits and auxi liary circuits not connected to the main circuits, normally the 
main circuit is connected to the frame, test ed voltage is applied at (time = 1 minute): 
——between control circuits, auxiliar y circuits and contactor frames 
——between all parts connect ed to parts that are insulated to all other parts under normal 
operating conditions 
c） Test voltage value 
Test voltage is a sine wave with a frequenc y between 45Hz and 65Hz. On empty load, after 
adjusting the voltage as per requirement, when short circuit the test terminal, short-circuit 
current of at least 0.2A can be generated. Power should not be tripped when the current is less 
than 0.1A (if a power tripping device is installed). 
 
For main circuits, control circ uits and auxiliary circuits no rmally connected to the main 
circuits, see Table 21 fo r their test voltage. 
 
Table 21 Test voltage value for pow er frequency withstand voltage 
Rated insulated voltage Ui 
V Voltage value for power frequency withstand 
voltage (AC)  (r.m.s) 
V 
       U i ≤60 
60＜ Ui ≤300  
300＜ Ui ≤690 1 000 
1 500 
2500 
 
For main circuits and control circuits and a uxiliary circuits not nor mally connected to the 
main circuits: 
—— When rated insulated voltage Ui ≤60V, power frequency withstand voltage = 1,000V ； 
——When rated insulated voltage Ui ＞60V, frequency withstand voltage = 2Ui+1,000V, but 
no less than 1,500V. 
For contactors in SELV circuits , voltage between the loop of powered parts in SELV circuits 
and other loops should be at least 4,000V. 
d）Test result 
If no disruptive discharge occurs (see 9.3.3.4.1b), th e test is considered to have been passed 
successfully 9.3.3.5 Making and breaking capabilities 9.3.3.5.1 General test conditions When verifying the making and breaking capabiliti es, the contactors being tested should meet 
the requirements in 9.3.2.1. 4-pole contactors should be test ed as 3-pole contactors. Poles not  in use and neutral should be 
connected to frame. Tests performed on 3 adjacent poles can represent all poles. 
Test should be performed as per requirements in Table 8 and free of error (For test evaluation, 
see 9.3.3.5.4b) Control power voltage = 110%Us in half of the operating cycles, and = 85%Us in the other 
half. The wiring of the main circu its should be the same with  the normal operating of the 
contactors. Control circuits and auxiliary circuits, esp ecially the electromagnetic coils, can be 
supplied by another independent power source,  which should supple the same current and 
voltage as per requirements. GB 17885—200× 
 
  9.3.3.5.2 Test circuits 
a） Test circuits in figure 11 ～14 are for the following tests: 
Figure 11:  Single pole contactor singl e phase AC test circuit diagram; 
Figure 12:  Dual pole cont actor single phase AC test circuit diagram; 
Figure 13:  3-pole contactor or 3-single phase contactor 3-phase AC test circuit diagram; 
Figure 14:  4-pole contactor 3-phase 4-wire AC test circuit diagram; 
Details of the circuit diagram should be described in the test report. 
b） Prospective short-circuit current of the power  end of the contactor should be no less than 
10 times the test current. 
c） Test circuit is composed of test power S, tested contact D and the load circuit. 
d） Load circuit is composed of parallel resist or hollow reactors. Any tubular reactors should 
be in parallel connection with the resist or shunt, the value of which should be 0.6 ％of the 
current passing the resistor. 
Should there be any requirements for transient recovery voltage, use a parallel resistor and 
capacitor to replace 0.6 ％resistor shunt to connect to the load. For complete load circuit 
diagram, see Figure 15. 
e） Under the specified test voltage, adjust th e load to meet the following requirements: 
 ──The current, power factor and power frequency recovery vo ltage values specified in 
Table 8   ──The oscillation frequency f of the transi ent recovery voltage and over-oscillation 
coefficient γ 
Over-oscillation coefficient γ is the ratio of transient re covery voltage peak value U
1 and the 
zero current transient power frequency r ecovery voltage shunt transient value U 2 (see Figure 
16) , i.e. 
  
f） Test circuit should be directly connected to ground at one point. Its location should be 
described in test report. 
g）All parts of contactors that connect to ground in normal us e (including housing and metal 
netting) should be insulated to ground in test , and connected to the sp ecified points in Figure 
11～14. 
To detect the faulty current, a fuse compone nt F should be connected between the part by 
which the device connects to the ground and ground points (as shown in Figure 11 ～14). The 
fuse component should use coppe r wires with a diameter of Φ0.8mm and a length of 50mm 
or similar. The predicted faulty current should be 1 ,500A±10 ％, except for those specified in 
Note 2 and Note 3. Current restricting resistor should be used if necessary. 
Note 1: Copper wires with a diameter of Φ0.8mm melts in half period wave under 1,500A 
current (frequency between 45Hz and 60Hz). Note 2: According to product specification, fo r small capacity device (predicted faulty 
current < 1,500A) the smaller copper wires with the same melting time as in Note 1 should be used (see Note 4).  
Note 3: In power systems where there’s a designat ed neutral, small predicted faulty current is 
allowed if agreed by manufacturers. Smaller copper wires should be used (see Note 4).  
Note 4: In fuse component circuits, the correl ation between the predicted faulty current and 
copper wire is as follows: GB 17885—200× 
 
 
    
Table 22 Correlation between the predicted fa ulty current and copper wire diameter 
Copper wire diameter 
mm Predicted faulty current in the faulty circuit tested 
A 
0.1 0.2 0.3 0.4 0.5 0.8 50 
150 300 500 800 
1 500 
 
9.3.3.5.3 Features of transient recover voltage 
Here requires contactors suitable for category AC －7b. 
Transient recover voltage is to simulate se parate motor load (inductive load) circuit 
circumstances, the oscillation frequency f should be adjusted to the value resulting from the 
formula below, tolerance = ±10%: 
 
Where, f—— oscillation frequency, kHz 
I
c——breaking current, A 
Ue——rated operating voltage, V. 
 Over-oscillation coefficient γ should be adjusted to the value resulting from the formula 
below, tolerance = ±0.05: 
 
Where, U
1, U2 see Figure 16 (see 9.3.3.5.2e) 
To obtain the reactance value need ed, reactors can be connected in  parallel. The reactors have 
the same time constants. Load terminal of the contactors should be connect ed to the terminal adju st the load circuit. 
Wiring should be as short as possible. Adjustme nt should be made after wirings have been 
fixed. Transient recovery voltage shoul d be adjusted on the whole lo ad circuit. Ground point should 
not be moved throughout. Procedur e is specified in Appendix C. 
9.3.3.5.4 Rated making and br eaking capabilities 
a） Rated making and breaking capabilities 
Contactors should be able to make and break current and operate as specified in Table 8.  
b） Characteristics of the making and br eaking test and af ter test condition 
When performing the making and breaking test  in 9.3.3.5 and when verifying the operating 
performance in 9.3.3.6.1, continuous ignition arc, el ectrode flashover, fuse component in the 
ground circuit blow  (see 9.3.3.5.2) and contact we lding should not occur.  
Dielectric characteristics are verified by dielectric test. A dopt basic sinusoidal wave test 
voltage, test voltage = 2U
e (no less than 1,000V), test voltage  as per 9.3.3.4.2b) 1) when main 
contact is at closed positi on (application time = 1 minute). 
Afterwards, contactors can operate as normal. GB 17885—200× 
 
  9.3.3.6 Conventional performance test 
The conventional performance test is used to verify if contactors meet the requirements in 
Table 10. Wiring of the main circuit is the same as the wiring of the contactor when under normal 
operating condition.  
Test circuit as per 9.3.3.5.2, load as per 9.3.3.5.3. Control voltage = 100 ％Us. 
9.3.3.6.1  Conventional operating performance  
Contactors should be able to make and break current and operate as specified in Table 10. 
9.3.3.6.2 Characteristics of the c onventional operating performa nce test and after test 
condition Requirements in 9.3.3.5.4b should be met. Dielectric  characteristics are verified by dielectric 
test. Adopt basic sinus oidal wave test volta ge, test voltage = 2U
e (no less than 1,000V), test 
voltage as per 9.3.3.4.2 b) 1) when main contact  at closed position (application time = 1 
minute). 9.3.4 Characteristics under shor t circuit circumstances  
This test is used to verify if contactors m eet requirements in 8.2.5.Procedures, test sequences 
and after test contactor condition re quirements are provided in 9.3.4.1 and 9.3.4.2. 
9.3.4.1 General conditions for short circuit. 9.3.4.1.1 General requirement 9.3.2.1 Application of ge neral requirements 
Contactors are operated under 8.2.1 requirements. It s operation under empty load should also 
meet requirements. 9.3.4.1.2 Test circuit 
a） Circuits in Figure 17 ～20 are for the following tests: 
Figure 17:  Single pole contactor singl e phase AC test circuit diagram; 
Figure 18:  Dual pole cont actor single phase AC test circuit diagram; 
Figure 19:  3-pole contactor 3-single  phase AC test circuit diagram; 
Figure 20:  4-pole contactor 3-phase 4-wire AC test circuit diagram. 
Details of the circuit diagram should be described in the test report. 
b） Power S supple for the circuit composed of resistor R
1, Reactor X and test contactor D. 
Power supply should be sufficient for contacto r characteristics to be verified under all 
circumstances. Resistor and reactor should be  adjusted to meet requirements. Reactor X 
should be tubular and in parall el connection with resistor R 1.  
To obtain the reactor value needed, reactors can be connected in parallel, and only when the 
reactors have the same time constants. As the translient recovery vo ltage of the large scale tubula r reactor test circuit cannot 
represent the normal operating c onditions, unless manufactures  specify otherwise, each 
reactor is in parallel connection with a breaking current. Its value is approx. 0.6 ％of the 
current passing the reactor. 
c） In each test circuit (Figure 17 ～20), the resistor should be connected between power S 
and tested contactor D, the positi ons at which device A and sensors l
1,l2,l3 are connected may 
be different from Figure 17 ～20. Wiring connecting contactors to  circuit should be described 
in the test report. 
When the test current is less than the ra ted limiting short circuit current, additional 
impendence is normally required between load si de of contact and th e short circuit point. 
Additional impendence can also be connected at the power side, which should be noted in the 
test report. GB 17885—200× 
 
 
   Unless manufactures have made agreements with users and specified in th e report, test circuit 
should be as shown in Figure 17 ～ 20. There should be only one ground point, which can be 
the short circuit point, the ne utral point or others as appr opriate. Grounding methods should 
be noted in the test report. 
d）See 9.3.3.5.2g, also see Figure 17, 18, 19, 20. 
9.3.4.1.3 Power factor of circuit 
The power factor should be identified as per requirements and should be noted in the test 
report.  See Appendix D for the two methods on how to identify power factor. Power factor of the multi-phase circuits should be considered as the average value of the individual values. The power factor  should be chosen as per Table 23. 
The difference between the average value and th e max. or min. values should be within ±0.05. 
 
Table 23 Correlation of the power factor, peak value coefficient and the test current 
Test current (I) 
kA Power factor (cos φ) 
 Peak value coefficient (n) 
 
         I ≤1.5 
1.5﹤I≤3.0 
3.0﹤I≤4.5 
4.5﹤I≤6.0 0.95 
0.9 0.8 0.7 1.41 
1.42 1.47 1.53 
 
Peak value coefficient is the ratio of shor t circuit current peak value and valid value.  
9.3.4.1.4 Adjustment to the test circuit When adjusting the test circuit, use wires (the  resistance of which can  be ignored) to replace 
the device. Wires should be as short as possible.  
Under the applied voltage , adjust resistor R
1 and reactor X to obtain the test current equal to 
rated short circuit breaking cap ability and power factor spec ified in 9.3.4.1.3. To test the 
contactor’s breaking and making ca pabilities by verifying the se t value of the waveform, the 
circuit must be adjusted to guarantee prospective making current is achieved.  
Note: Applied voltage of making current must ge nerate the power frequency recovery voltage 
as specified (see 9.3.2.2.3, note 1). All poles should be connected to  power at the same time and the time recording for current 
waveform should be at least 0.1 second. 9.3.4.1.5 Test procedure After the test circuit has been adjusted as  specified in 9.3.4.1.4, replace the temporary wires 
with the tested contactors. Contactors and relevant  SCPD should be inst alled and connected as normal. Each circuit 
should use wirings with max. length of 2.4m (as per operating current). 
3-phase test can be considered as covering single-phase circumstance.   
9.3.4.1.6 Descriptions for the wave form a) Identifying the applie d voltage and the power fr equency recovery voltage. 
Identify from the relevant wave form diagrams for the contactor breaking test, as specified in 
Figure 21.  The voltage on the power side is  measured in the first complete cycle when all arcs go out 
and the voltage high frequency com ponents clear away (see Figure 21). 
b) Identifying the prospective breaking current GB 17885—200× 
 
  Compare the current waveform curve when adju st the circuit to the one from the contactor 
breaking test to identify the pr ospective breaking current (see  Figure 21). The AC component  
of the prospective breaking curren t equals to the valid value of the AC component at the 
waveform curve of the setting current at the arc contactor breaking transient (Figure 21, curve 
a A2/2√2). Prospective breaking current should be th e average value. The difference between 
the any prospective breaking current at any phase and the average value should not exceed 
10% of the average value.  
c） Identifying the prospective breaking current peak value 
The prospective breaking current peak value sh ould be identified by the set current wave 
form when adjusting the circuit, whic h is the value in Figure 21curve a A 1. In a 3-phase test, 
the highest current value corresponds to the 3 A 1s. 
Note: For a single-phase contactor single-phase test, the value obtained from the set current 
wave form may be different from the actua l making current value. This depends on the 
making transient phase angle. Therefore, this can be resolved by using phase making devices. 
9.3.4.2 Restricting the short circuit current Contact and SCPD in parallel connection should perform the test in 9.3.4.2.1 and 9.3.4.2.2, 
under the maximum I
e and U e. 
For electromagnetic contactors, control power should be supplied by a separate power source. 
SCPD should meet the requirement in 8.2.5. If SCPD is breaking device of which the set 
current can be adjusted, the test should be  performed under the maximum current of the 
breaking device. During the test, all apertures on the housing should be closed as per normal operating 
conditions. Gates for lids should be fastened. 
A new sample can be used for each ope ration in the perspective current I
r and I q test 
procedures.  9.3.4.2.1 Perspective current I
r test 
Current should be adjusted to the specified value in Table 12.  
Connect the contactor and SCPD in parallel in the circuit. Follow the procedures below: 
 
a） Before the test,  SCPD and contactor are cl osed. Use another device to connect the short 
circuit current. Use SCPD to perform a breaking operation. 
b） Use the contactor to connect the short circ uit current. Use SCPD to perform a breaking 
operation. 
Select the power factor from Table 23 in 9.3.4.1.4. 9.3.4.2.2 Rated restrictive short circuit current I
q test 
Only perform this test when current I q is higher than I r. 
Adjust current I q to rated restrictive short circuit current. 
If SCPD is the fuse, the test current should be within the restriction of the fuse. Fuse should 
allow for peak value current I p and I2t.  
Connect the contactor and SCPD in parallel  in the circuit. Perform the following: 
a） Before the test,  SCPD and contactor are cl osed. Use another device to connect the short 
circuit current. Use SCPD to perform a breaking operation. 
b） Use the contactor to connect the short circ uit current. Use SCPD to perform a breaking 
operation. 
9.3.4.2.3 Determine the test result If all conditions below have been met, it is considered that the I
r current test and I q current test 
(when applicable)  have been passed. GB 17885—200× 
 
 
   a） SCPD successfully breaks the fa ulty current and the fuse or  the fuse component between 
the housing and the power is not blown. 
b） The gates or lids on the hous ing are not parted and can be  opened. Housing deformation 
is allowed as long as housing prot ection rating is no lower than IP2X. 
c） Wiring and terminals are intact and not separated.  
d） Insulated base should not contain chips which could damage the energised part 
installations. 
e） Discharge should not happen on the surface part of the housing. Contactor damage may 
happen and may be unsuitable for further use. 
9.3.5 Overload current withstanding capability Contactors are installed, connected and operated as specified in 9.3.2. 
Each pole of the contactor is tested at the sa me time as per overload current requirement and 
time specified in 8.2.4.3. It is performed in room temperature under convenient voltage. 
Samples should have no noticeable de formation or damage after test. 
Note: The resulted I
2t value (Joule integral) cannot be  used for assessing contactor 
performance under the short circuit conditions. 9.3.6 Routine test The routine test is performe d after each contactor is be ing manufactured or after the 
manufacture. The purpose is to verify  they meet all the requirements. 
9.3.6.1 Overview Routine test conditions should correspond to the specifications in 9.1.2. Actuation range tests 
in 9.3.3.2 can be performed under common ambience air temperature, but must be calibrated 
under the normal ambience conditions. 9.3.6.2 Actuation and actuation range The purpose is to verify the actuation characte ristics within the range specified in 8.2.1.2. 
Note: It is not necessary to achieve thermal equilibrium for this test. 
9.3.6.3 Dielectric  test 
Test should be performed on dry, intact contactors. Test voltag e is as specified in 9.3.3.4.2c). 
Test time = 1 second. Test voltage is applied: a) Between each pole when main contact is in  the closed position (Main contact should be 
open for parallel connections)  b) Between each pole and frame the main cont act is in a closed position. When the whole 
contactor is enclosed in a insulated housing, it should be installed on a metal plate. Test 
voltage is applied between each pole of  the contactor and the metal plate. 
c) Between the terminals of each pole when the main contact is open. d) Control circuit and au xiliary circuit are as specified in 9.3.3.4.2b) 2). 
It is not necessary to use the foil in 9.3.3.4.1a). If the tested contactor meets the requirements in 9.3.3.4.2d), the te st is considered to have 
been passed successfully. 
 GB 17885—200× 
 
   
  Figure 1 Self Tapping  
Figure 2 Treading Cutting Screw 
Figure 3 Ball Pressure Test Device BallSampleGB 17885—200× 
 
 
    
Measurement Unit: mm  
Figure 4: Bending Test Device 
 
Measurement Unit: mm Clamps 
Platform 
Dowel Hole 
Qualit y 
A-Type B-Type GB 17885—200× 
 
   
Figure 5:  A-Type, B-Type Modelling Gauge 
 
 
 
Measurement Unit: mm 
Parts Material: ①Polyamide; ②③④⑤ Fe360 Steel 
 
Figure 6:   Devices for Pendulum Impact Test 
 
 
 Figure 7: Sample Racks for Mechanical Shock Impacts Measurement Unit: mm  Pivot Plywood 
Pivot GB 17885—200× 
 
 
    
 
Figure 8:  Devices for Pendulum Impact Test Measurement Unit: mm 
 
 
 
 
 
Note: Ball should be in contact with sample when vertical. 
 
Figure 9:  Ball Impact Test Frame 
Sample 
Installation Rac k
Ball Starting 
Point Ball Starting Point 
Ball Impact Point Ball Impact 
Point 
Steel Rack 
Steel Su pportin g Steel Su pportin gSample SampleGB 17885—200× 
 
   
 
Material: Metal (unless specified otherwise). 
Measurement Unit: mm 
Tolerance of Dimensions ( unless specified otherwise) ： 
 
Angle ：   0 
 − 1 0 ′ 
 Linear: 
  0 
Above 25mm: −0.05 
Below 25mm:  ±0.2 
Articulation point rotating a ngle (one direction only): 
 
Figure 10:  Articulation Test 
 Handle 
Shield 
Insulation 
Material  
Baffle 
Articulation 
Point Edge 
Bevelling 
Cylinder 
Sectio n 
Sectio n sphericity GB 17885—200× 
 
 
    
 
 
S－power 
Ur1, U r2—voltage sensor 
F—fuse component (See 9.3.3.5.2g) 
Z—load circuit (See figure 15) 
RL— fault current resistor  
D—contactor tested (including connecting cable) B—temp correcting wires for adjustment 
I
1—current sensor 
T—ground point (one point only for load side or power side) 
Figure 11: Test circuit for single-pole contactor 
single phase AC making and breaking capabilities.
 
 
 
       S－power 
Ur1, U r2, U r3— voltage sensor 
V－voltage gauge 
N—power neutral (or designated neutral) 
F— fuse component (See 9.3.3.5.2g) 
Z— load circuit (See figure 15) R
L— fault current resistor  
D—contactor tested (including connecting cable) 
B—temp correcting wires for adjustment 
I1, I2— current sensor 
T—ground point (one point only for load side or power side) 
Note 1:  U
r1 can be set between phase and neutral. 
Note 2:  F should be co nnected at the power phase 
when device is expected to be used with ground 
system or in 4 pole device neutral tests.  
Note 3:  In US or Canada, F should be connected at: 
－Power phase when device marked with single 
voltage  Ue 
－Neutral when device marked with dual voltage 
Figure 12: Test circuit for bipolar contactor GB 17885—200× 
 
 
   single phase AC making and breaking 
capabilities.   
 
 
S－power 
Ur1, U r2, U r3, U r4, U r5, U r6—voltage sensor 
V－voltage gauge 
N—power neutral (or designated neutral) 
F—fuse component (See 9.3.3.5.2g) 
Z—load circuit (See figure 15) 
RL— fault current resistor  
D—contactor tested (including connecting cable) 
B—temp correcting wires for adjustment 
I1 、I2 、I3—current sensor 
T—ground point (one point only for load side or 
power side) Note 1:  U
r1, U r2, U r3 can be set between phase and 
neutral. 
Note 2:  F should be co nnected at the power phase 
when device is expected to be used with ground 
system or in 4 pole device neutral tests.  
Note 3:  In US or Canada, F should be connected at: 
－Power phase when device marked with single 
voltage  Ue 
－Neutral when device marked with dual voltage   
Figure 13:  Test circuit for 3-pole contactor 
single phase AC making and breaking 
capabilities. S－power 
Ur1, U r2, U r3, U r4, U r5, U r6—voltage sensor 
V－voltage gauge 
N—power neutral (or designated neutral) 
F—fuse component (See 9.3.3.5.2g) 
Z—load circuit (See figure 15) 
RL— fault current resistor  
D—contactor tested (including connecting cable) 
B—temp correcting wires for adjustment 
I1 、I2 、I3—current sensor 
T—ground point (one point only for load side or 
power side) Note 1:  Ur1, Ur2 and Ur3
 can be set between phase 
and neutral. 
Figure 14:  Test circuit for 4-pole contactor 
single phase AC making and breaking 
capabilities. 
 
 
 GB 17885—200× 
 
 
   
 
S—power 
D—device tested C—selector switch B— diode 
A—recorder 
R
a—resistor 
G—high frequency generator R—load circuit resistor X— load circuit resistor (see 9.3.3.5.2 d) 
R
p—parallel resistor  
Cp—shunt capacitor 
I1,I2,I3—current sensor 
 See figure for high frequency generator position (G) and diode position (B). Connection to ground can 
only be set at positions shown. 
 
Figure 15: Adjustment for load circuit 
 GB 17885—200× 
 
  
 
                                               Transient zero current  
 
Figure 16:  Sketch map for recovery voltage between arcing-extinguishing contactors under ideal 
circumstances  
 
 
 Curren t
VoltageTime 
Time GB 17885—200× 
 
 
    
 
S－power 
Ur1, U r2—voltage sensor 
V－voltage gauge 
A－circuit closing device 
R1—adjustable resistor 
F— (See 9.3.4.1.2d) 
X—adjustable resistor R
L— fault current resistor  
D—contactor tested (including connecting cable) 
B—temp correcting wires for adjustment I
1—current sensor 
T—ground point (one point only for load side or 
power side) r—resistor shunt (see 9.3.4.1.2b) 
Note: Adjustable load X and R
1 can be connected 
on the high or low voltage side; Apparatus A should be connected at the low voltage side. 
Figure 17: Circuit diagram for testing single-
pole connector single-phase AC short circuit making and breaking capabilities. 
 
 
 
  
 
  
 
  
 
S－power 
U
r1, U r2, U r3—voltage sensor 
V－voltage gauge 
A－circuit closing device 
R1—adjustable resistor 
N—power neutral (or designated neutral) 
F—fuse component (See 9.3.4.1.2d) 
X—adjustable resistor R
L— fault current resistor  
D—contactor tested (including connecting cable) 
B—temp correcting wires for adjustment I
1, I2—current sensor 
T—ground point (one point only for load side or 
power side) r—resistor shunt (see 9.3.4.1.2b) 
Note 1: Adjustable load X and R
1 can be connected 
on the high or low voltage side; Apparatus A should be connected at the low voltage side. 
Note 2:  U
r1 can be set between phase and neutral. 
Note 3:  F should be co nnected at the power phase 
when device is expected to be used with ground 
system or in 4 pole device neutral tests.  Note 4:  In US or Canada, F should be connected at: 
－Power phase when apparatus marked with single 
voltage  Ue 
－Neutral when apparatus marked with dual 
voltage   GB 17885—200× 
 
 
   Figure 18:  Circuit diagram for testing bipolar 
connector single-phase AC  short circuit making 
and breaking capabilities. GB 17885—200× 
 
   
 
 
 
 
 
 
S－power 
Ur1, U r2, U r3, U r4, U r5, U r6—voltage sensor 
V－voltage gauge 
A－circuit closing device 
R1—adjustable resistor  
N—power neutral (or designated neutral) F—fuse component (See 9.3.4.1.2d) 
X—adjustable resistor 
R
L— fault current resistor  
D—contactor tested (including connecting cable) 
B—temp correcting wires for adjustment 
I1 , I2,  I3—current sensor 
T—ground point (one point only for load side or 
power side) r—resistor shunt (see 9.3.4.1.2b) 
Note 1: Adjustable load X and R
1 can be connected 
on the high or low voltage side; Apparatus A should be connected at the low voltage side. 
Note 2:  U
r1 , U r2 , U r3 can be set between phase 
and neutral. Note 3:  F should be co nnected at the power phase 
when device is expected to be used with ground 
system or in 4 pole device neutral tests.  Note 4:  In US or Canada, F should be connected at: 
－Power phase when apparatus marked with single 
voltage  Ue 
－Neutral when apparatus marked with dual 
voltage   Figure 19:  Circuit diagram for testing 3-pole 
connector single-phase AC short circuit making 
and breaking capabilities. 
 
 
S－power 
U
r1, U r2, U r3, U r4, U r5, U r6—voltage sensor 
V－voltage gauge 
A－circuit closing device 
R1—adjustable resistor  
N—power neutral (or designated neutral) 
F—fuse component (See 9.3.4.1.2d) 
X—adjustable resistor 
RL— fault current resistor  
D—contactor tested (including connecting cable) B—temp correcting wires for adjustment 
I
1 , I2,  I3—current sensor 
T—ground point (one point only for load side or power side) 
r—resistor shunt (see 9.3.4.1.2b) 
Note 1: Adjustable load X and R
1 can be connected 
on the high or low voltage side; Apparatus A 
should be connected at the low voltage side. 
Note 2:  U r1 , U r2 , U r3 can be set between phase 
and neutral. 
Note 3:  Connecting wires C1 and C2 can be 
omitted for additional neutral and adjacent pole tests. 
Figure 20:  Circuit diagram for testing 4-pole 
connector single-phase AC short circuit making and breaking capabilities. 
 GB 17885—200× 
 
   
 
a)  Test circuit settling wave form 
 
 
 
 
b)  Breaking “O” or making “CO” test wave form 
 Current 
Current Voltage 
Voltage 
Makin g
Brakin g
Prospective  making peak current  
Prospective  symmetric breaking current (effective value)  
Applied voltage  (effective value)  GB 17885—200× 
 
 
   
 
Note 1: After test current is generated, amplit ude of voltage wave form changes with circuit 
closing device, adjustable impedance, voltage se nsor positions, and change s as per test circuit 
diagrams. Note 2: Presume settling wave and test wave make at the same time. 
 
Figure 21:Legend for sing-pole contactor si ngle-phase AC short circuit making and 
breaking test. 
 Power voltage  (effective value)  
Making capability (peak value)  
Breaking capability  (effective value)  GB 17885—200× 
 
   
Appendix A (Guideline  Appendix) Contactor Terminal  Marking and Identification 
A.1 General 
Contact terminal marking is to provide the function of each terminal or its relative position and other usage information.  A.2 Contactor Terminal Marking and Identification 
 
A.2.1 
Coil Terminal Marking and Identification 
Electromagnetism contactor coil terminal are marked by alphanumerics such as A1, A2;   
 
 
 
For tapped coils, the tapped terminal  should be marked as A3, A4, etc. 
For example: 
 
 
 
Note: Following the sequence, both the input and output can be odd or even numbers. For coils with two windings, the first winding termin als are marked as A1, A2; while the second winding 
terminals are marked as B1, B2. 
 
 
 
A.2.2 Main Circuit Terminal Marking and Identification Main circuit terminal should be marked by separate alphanumberic system.  
 
 
Note: The two current marking methods (i.e.1-2 and L1-T1) will be replaced by the method mentioned above. 
In other words, terminals can be identified by the wiring diagram. 
 
A.2.3 Auxiliary Circuit Terminal Marking and Identification 
Auxiliary circuit terminals should be marked and identified by 2 digits: ones place is function, tens place is sequence. For example: 
 
 GB 17885—200× 
 
 
    
A.2.3.1 Function Number 
Function number 1 and 2 indicate normally closed circuits, while 3 and 4 indicate normally open 
circuits. 
 
Note: Dots indicate sequence number, must be with the corresponding numbers.  
Terminals for converting contact element circuit shou ld be marked with function number 1, 2 and 4. 
 
 
 
Function number 5 and 6 (normally closed circuit), 7 and 8 ( normally open circuits) indicate special 
functions. 
For example: 
 
 
                   Time closing breaking contact   Time closing making contact  
 Terminals for converting contact element circuit with  special functions should be marked with function 
number 5, 6 and 8. 
For example: 
 
Time closing breaking and making converting contact 
 A.2.3.2 Sequence Number  Terminals belonging to the same contact element should use the same sequence number marking. 
All contact elements with the same function numbers should use different sub-sequence numbers. 
For example:  
 
4 contact elements               3 contact elements 
 
Appendix B (Guideline A ppendix) Procedure Test and Sample Quantity 
 
B.1 Procedure Test Test should be carried out as per Table B.1. Each group of procedure tests should be carried out following the sequences specified in the table. GB 17885—200× 
 
   
Table B.1 Procedure Test 
Procedure Test Procedure Test Case  Performance Testing 
Method 
A a.  temperature rise test 
b. operation and operation scope 
c. rated making and breaking capabilities 8.2.2 
8.2.1 
8.2.4.1  9.3.3.3 
9.3.3.1,9.3.3.2 
9.3.3.5  
 
B a.  dielectric performancea 
b. committed operational performance 
 8.2.3 
8.2.4.2  
 9.3.3.4 9.3.3.6
 
 
C a.  water resistance performance 
b. overload current stamina 
c. corrosion resistance performance  8.1.1.2 
8.2.4.3 
8.1.1.5  
 9.2.1.2 
9.3.5 
9.2.1.5  
 
D a.  durability of markings 
b. impact resistance performance 
c. measuring of clearance and (when 
necessary) creepage distance  8.1.12 
8.1.11 
8.2.3.2.3, 8.2.3.2.4  
 9.2.6 
9.2.5 
── 
 
E a.  mechanical performance of terminals 
b. performance tests on bolts and nuts for 
installations and repairs 
c. heat resistance performance 
d. test on abnormal heat resistance and fire 
hazards 
e. CTI testsb 8.1.6 
8.1.2 
8.1.1.3 
8.1.1.4 
── 
 9.2.4 
9.2.2 
9.2.1.3 
9.2.1.4 
9.2.1.6  
 
F a. aging property 
b. enclosure protection rating 8.1.1.1 
8.1.10  
 9.2.1.1 9.2.3
 
 
G Performance under short circuit circumstances 8.2.5 
 9.3.4 
 
a No need to measure clearance and creepage distance 
b When no i nsulation material samples to be tested  
 
B.2 Sample Quantity 
 
See Table B.2 for sample quantity. 
 
Table B.2 Sample Quantity 
Procedure Test Sample Quantity  
A 
B C 
D 
E 
F 
G 3 
3 1 1 
1 
1 
4
a 
aWhen necessary, a new sample can be used for each task (see 9.3.4.2). 
 
 
 
 
 
Each sample in a procedure test must pass its test in the procedure. If all samples pass all tests, then 
the test is approved. If any single test fails, then th e procedure test fails. Further tests must be carried 
out with new test samples until all samples pass their tests.  
 GB 17885—200× 
 
 
    
Appendix C (Guideline Appe ndix) Instructions for Load Circuit Adjustment 
Load circuit can be adjusted in a few wa ys to meet the specifications in 9.3.3.5.3. For 
example: For circuit diagram, see figure 16. The oscillation frequency f and γ of transient recovery voltage mainly depends on the natural 
oscillation frequency and the damping of the load circuit. As these values are not relevant to 
the applied voltage and frequency, AC power can be used to adjust the load circuit, the 
voltage and frequency of whic h can be different from those of the device being tested. A 
diode breaks the circuit when current crosses ze ro, the oscillation wave form of the recovery 
voltage will be shown on cathode-ray oscill oscope. The scanning frequency of the 
oscilloscope should be the same as the power frequency (see figure C.1). 
To obtain reliable measurement, load circuit is  powered by high-frequency signal generator G. 
The high-frequency signal ge nerator should supply a voltage suitable for diode. The 
frequency of the selected generator is as below: 
a）2 kHz when test current  ≤ 1 000 A ； 
b）4 kHz when test current  > 1 000 A 。 
 
The following are in series  circuit with the generator: 
——For a ）and b ）, resistor Ra is greater than voltage dropping resistor of the load circuit 
(Ra≥10 Z, while Z= √R
2 +(ωL)2 , and ω=2π×2 000s-1 or ω=2π×4 000s-1) 
——switching diode for transient cut-off, normally  used for computers, e.g. diffused silicon 
switching diode with forward current rating less than 1A As generator generates high frequency and load ci rcuit is in fact purely inductive, the applied 
voltage at the ends of the load  circuit is its peak value when current crosses zero. To ensure 
the load circuit parts are suitable, they must be tested on screen. Ma ke sure the transient 
voltage curve at the starting poi nt (see A in figure C.1) ha s virtually horizontal tangent. 
  Actual coefficient γ equals U11/U12. U11 is screen r eading. U12 is the reading between y-
axis of A and y-axis of the wave form when  high-frequency generato r stops supplying power 
to load circuit (see figure C.1). When observing the transient volta ge in load circuit and there 
is no parallel resistor Rp or parallel capacito r Cp, the natural oscill atory frequency can be 
read on screen.  If the natural oscillatory freque ncy is over the upper-limit of the f value, parallel resistor Rp 
or parallel capacitor Cp can be  connected to obtain suitable frequency value and coefficient γ. 
Resistor Rp should be non-inductive. Note 1: The higher frequency it generates, the easier it is to be observed and improved. 
Note 2: Other methods for identifying the frequency and coefficient γ can be adopted (e.g. the 
use of square-wave current).  GB 17885—200× 
 
  
 
Figure C.1 Measurement of coefficient γ Transient 
zero- current 
Unenergized 
circuit tracing GB 17885—200× 
 
 
    
Appendix D (Guideline Appendix) Methods for Identifying Short Circuit Power Factor 
 
Currently there is no precise way of identifying the short circuit power factor or the time 
constant. For the need of this guideline, one of the following methods can be adopted: 
Note: Other methods are in consideration. 
D.1 DC component 
Phase angle φ is measured via the asymmetrical curre nt DC component curve from the short 
circuit transient and contact breaking transient. Note: Not applicable when current is meas ured by current transformer, unless errors 
introduced by the following can be avoided: ──Time constant of the transformer and th e time constant calculated by its load 
──Magnetic saturation generated by transient magnetic flux and possible magnetic residual 
Step 1: To identify time constant L/R from DC component formula. 
DC component formula: Id＝I
d0e-Rt/L 
where,  
Id── DC component value  at t 
Id0──short circuit transient （t＝0）DC component value  
t──time from transient, s 
L/R──circuit time constant, s 
a. Id、Id0 and t can be obtained from the asymmetrical current DC component curve 
b. R/L obtained from DC component formula ； 
Step 2: To obtain phase-angle φ from φ＝arctg (ωL/R) 
where, 
ω = 2π f , f is power frequency 
  D.2 Measured by auxiliary generator  Use one generator coaxial with the test gene rator. Compare the phase of the auxiliary 
generator voltage with the test generator empty load voltage on the oscillogram. Then compare the current phase of the two generato rs. The difference between the phases is the 
power factor φ. 
 
 GB 17885—200× 
 
   
Appendix E (Guideline Appe ndix) Measurement of Clearance and Creepage Distance 
E.1 Basic Principles 
In E1 ～E12, the groove width X is a function of pollution degree , see table below: 
 
Table E.1 Correlation of groove width and pollution degree 
 
Pollution degree  Groove Width (min.) 
mm 
1 0.25 
2 1.00 
3 1.50 
4 2.50 
 
 
If relevant clearance is less than 3mm, groove width can be reduced to 1/3 of the clearance. 
See Figure E1 ～E12 for measuring method of clearance and creepage distance. There is no difference 
between clearances and grooves or any types of insu lation. (Clearances are indicated by dotted lines, 
while creepage distances are indicated by 
  in the figures.). 
and: 
——Presume arbitrary angle is bridged by the insulation joint with a width of X mm at the least 
advantageous position ( see Figure E.4); ——When the span over the groove is greater than X mm, measure the creepage distance along the 
groove contour ( see Figure E.3); 
——When the moving part is at the least advant ageous position, measure the clearance and the 
creepage distance. 
 
E.2 Use of Rib  
As the ribs can reduce the effect of pollution and provide good performance on drying, they substantially 
reduced the current leakage. If the minimum height of  the rib is 2mm, the creepage distance can be 
reduced to 0.8 times of the requirement.   
 
 
 Min. height 
of the rib 
Minimum bottom width of the rib depending on 
mechanical requirement GB 17885—200× 
 
 
    
 
Condition: Track of creepage distance includes grooves with a parallel edge  or convergent edge  (width 
less than Xmm, any depth). 
Rule: Creepage distance and clearance as shown in figure are measured as the span over the groove. 
Figure E.2 
 
 
Condition: Track of creepage distance includes grooves with a parallel edge  (width greater than or equals 
to Xmm, any depth). 
Rule: Clearance is the distance of the dotted line.  Creepage distance is the contour of the groove. 
Figure E.3 
 
 
Condition: Track of creepage distance includes a V groove (width greater than Xmm). 
Rule: Clearance is the distance of the dotted line.  Cr eepage track follows the contour of the groove, but 
short-circuited by Xmm connection. 
Figure E.4 
 
 
Condition: Track of creepage distance includes a rib. GB 17885—200× 
 
  Rule: Clearance is the shortest distance by which the air travels over the rib. Creepage track follows the 
contour of the groove. 
Figure E.5 
 
Condition: Creepage distance includes an unwelded joint and a groove with the width of each edge less 
than Xmm. 
Rule: Creepage distance and clearance is dotted line shown. 
Figure E.6 
 
 
 
Condition: Creepage distance includes an unwelded joint and a groove with the width of each edge greater 
than or equal to Xmm. 
Rule: Creepage distance is dotted line shown. Creepage track follows the contour of the groove. 
Figure E.7 
  
 
Condition: Creepage distance includes an unwelded joint and a groove with the width of one edge less than 
Xmm and another edge greater than or equals to Xmm. 
Rule: Creepage distance and clearance is as shown in the figure. 
Figure E.8 GB 17885—200× 
 
 
    
 
Condition: Creepage distance through an unwelded joint is less than the creepage distance over a separator. 
Rule: Clearance is the shortest distance by which the air travels over the top of the separator. 
Figure E.9 
 
 
 
Condition: The clearance between the bolt tip and th e concave is wide enough to be taken into 
consideration. 
Rule: Creepage distance and clearance is as shown in figure. 
Figure E.10 
  GB 17885—200× 
 
   
 
Condition: The clearance between the bo lt tip and the concave is too narrow to be taken into consideration. 
Rule: When the distance equals to Xmm,  creepage distance is from bolt to wall. 
Figure E.11 
  
 
 
Clearance = d ＋D 
Creepage Distance = d ＋D 
C’── Movable Parts 
Figure E.12 
  GB 17885—200× 
 
 
    
Appendix F (Guideline Appe ndix) Contactor’s Rated Im pulse Withstand Voltage 
 
This Appendix provides data on how to select electric system or devices used in part of its circuit. Table F.1 and F.2 provide examples of correlations between power system nominal voltage and rated impulse withstand voltage for relevant device. 
The rated impulse withstand voltage provided in Table F.1 and F.2 are based on the characteristics of 
surge suppressors. 
It should also be known that the overvoltage controlling the values in Table F.1 and F.2 can also be 
obtained from an appropriate power system, e.g. with appropriate resistance or power cables.  
When other methods than surge suppressors are used for cont rolling overvoltage, the correlation 
between the power system nominal voltage and device rated impulse withstand voltage is specified in 
GB/T 16895.12. 
 
 
Table F.1 The correlations of installation category, power system nominal voltage and rated impulse 
withstand voltage in a insulation coordination system cont aining overvoltage restrictions. 
 
Nominal voltage of power system 
(≤Rated insulation voltage of contactors.) Priority value of" rated impulse withstand 
voltage 
（1.2/50µs ， Uimp at 2000m ） 
kV 
 
Installation Category 
IV  
 III II  I Max. 
rated 
working 
voltage 
to 
ground. 
 
Valid 
value for 
AC or 
DC, 
V 
 
Valid 
value for 
AC, V 
Valid 
value for AC, V 
 
Valid value 
for AC or 
DC, 
V 
 
Valid value 
for AC or DC, 
V Device 
power 
grade 
(house-
service 
wire) Power 
distribution 
circuit 
grade Load 
level 
(device) Special 
protection 
level 
50 － 
 － 
 12. 5, 24, 
25, 30, 
42, 48  60-30  
 1.5 
 0.8 0.5 0.33 
100 66/115  66 60 － 2.5 1.5 
 0.8 0.5 
150 120/208 
127/220  115, 120, 127  
 110, 120  
 220-110 240-120
 4 2.5 1.5 
 0.8 
300 220/380 
230/400 
240/415 
260/440 
277/480  220, 230, 240 
260, 277  
 220 440-220  
 
  6 4 2.5 
1.5 
 
600 347/600 
380/660 
400/690 
415/720 
480/830  347, 380, 400 
415, 440, 480 
500, 577, 600  
 480 960-480  
 8 6 4 2.5 
1000 － 660, 690, 720 
830, 1 000  1000 － 
 12 8 6 4 
 GB 17885—200× 
 
   
If the device is only used for underground power dist ribution systems or systems with an overvoltage 
restriction which can reduce the lightening severit y, its rated impulse withstand voltage can be 
selected from Table F.2 below. 
 
Table F.2 The correlations of installation category,  power system nominal voltage and rated impulse 
withstand voltage in a insulation coordination system  with overvoltage restrictions which can reduce 
the lightening severity. 
 
Nominal voltage of power system 
(≤Rated insulation voltage of contactors.) Priority value of" rated impulse withstand 
voltage 
（1.2/50µs ， Uimp at 2000m ） 
kV 
 
Installation Category 
IV  
 III II  I Max. 
rated 
working 
voltage 
to 
ground. 
 
Valid 
value for 
AC or 
DC, 
V 
 
Valid 
value for 
AC, V 
Valid 
value for AC, V 
 
Valid value 
for AC or 
DC, 
V 
 
Valid value 
for AC or DC, 
V Device 
power 
grade 
(house-
service 
wire) Power 
distribution 
circuit 
grade Load 
level 
(device) Special 
protection 
level 
50 － 
 － 
 12. 5, 24, 
25, 30, 
42, 48  60-30  
 0.8 0.5 0.33 － 
100 66/115  66 60 － 1.5 
 0.8 0.5 0.33 
150 120/208 
127/220  115, 120, 127  
 110, 120  
 220-110 240-120
 2.5 1.5 
 0.8 0.5 
300 220/380 
230/400 
240/415 
260/440 
277/480  220, 230, 240 
260, 277  
 220 440-220  
 
 
 4 2.5 1.5 
 0.8 
600 347/600 
380/660 
400/690 
415/720 
480/830  347, 380, 400 
415, 440, 480 
500, 577, 600  
 480 960-480  
 6 4 2.5 1.5 
 
1000 － 660, 690, 720 
830, 1 000  1000 － 
 8 6 4 2.5 
Note: Table F.2 is also applicable for overvoltage protection from underground power distribution systems 
or protection which can reduce the lightening severity ( µ25). 
 
 
 
 GB 17885—200× 
 
 
    
Appendix G (Guideline Appe ndix) Electrically Heated Wire Ignition Test 
 
 
G.1 Every material is tested by 5 samples. Sample size = 150mm×13mm, with even thickness and 
representing the thinnest section of the component, and without burrs. 
 
G.2 Test uses nichrome ( 80％ nickel 、20％ chrome, no iron ) resistance wires with 0.5mm diameter, 
250mm±5mm length, and a cold resistance of 5.28 Ω/m. Resistance wires are connect ed to the adjustable 
power in a direct line. Adjust the power so th at the power loss within the resistance wires is 
0.26W/mm in 8s ～12s. Wrap the resistance wires around the sample 5 times with a gap of 6mm when 
cold.  
 
G.3 Samples wrapped in resistance wires are placed on a flat su rface. Connect the 2 terminals of the 
resistance wires to the adjustable power. Adjust th e power so that the power loss within the resistance 
wires is 0.26W/mm (see Figure G.1). 
  
G.4 Start the test, connect to the power so that the linear power by current is 0.26W/mm. 
  
G.5 The resistance wires are heat ed until the sample ignites. Cut o ff the power at ignition and record 
the time.  Stop the test if no ignition after 120 seconds. 
 For samples melted without ignition, stop the test  when samples are no lo nger in close contact 
with the 5 circles of resistance wires.
 
 
G.6 Test should be repeated with other samples. 
  
G.7 Material ignition time by the electrically heated wires are the average time from all samples.  
  
 
Figure G.1 Device for electrically heated wire ignition test