1971L0320 — EN — 03.01.1986 — 005.001 — 1
This document is meant purely as a documentation tool and the institutions do not assume any liability for its contents
►B COUNCILDIRECTIVE
of26July1971
ontheapproximationofthelawsoftheMember Statesrelating tothebrakingdevicesofcertain
categories ofmotorvehiclesandoftheirtrailers
(71/320/EEC)
(OJ L 202, 6.9.1971, p. 37)
Amended by:
Official Journal
No page date
►M1Commission Directive 74/132/EEC of 11 February 1974 L 74 7 19.3.1974
►M2Commission Directive 75/524/EEC of 25 July 1975 L 236 3 8.9.1975
►M3Commission Directive 79/489/EEC of 18 April 1979 L 128 12 26.5.1979
►M4Commission Directive 85/647/EEC of 23 December 1985 L 380 1 31.12.1985
Amended by:
►A1Act of Accession of Denmark, Ireland and the United Kingdom of Great
Britain and Northern IrelandL 73 14 27.3.1972
Corrected by:
►C1Consolidated text of corrigenda to instruments published in Special
Editions1952-72, p. 96 (71/320/EEC)
►C2Corrigendum, OJ L 247, 23.9.1975, p. 36 (75/524/EEC)
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COUNCILDIRECTIVE
of26July1971
on the approximationof the lawsofthe Member States relating to
the braking devices of certain categories of motor vehicles and of
theirtrailers
(71/320/EEC)
THE COUNCIL OF THE EUROPEAN COMMUNITIES,
Having regard to the Treaty establishing the European Economic
Community, and in particular Article 100 thereof;
Having regard to the proposal from the Commission;
Having regard to the Opinion of the European Parliament(1);
Having regard to the Opinion of the Economic and Social
Committee(2);
Whereas the technical requirements which motor vehicles must satisfy
pursuant to national laws relate, inter alia , to the braking devicesof
certain categoriesof motor vehiclesand of their trailers ;
Whereasthos e requirementsdiffer from one Member State to another;
whereas it is therefore necessary that all Member States adopt the samerequirements either in addition to or instead of their existing rules, inorder, in particular, to allow the EEC type approval procedure whichwasthe s ubject of the Council Directive of 6 February 1970 on the
approximation of the lawsof the Member Statesrelating to the type
approval of motor vehiclesand their trailersto be applied in res pectof each type of vehicle(
3);
Whereas the harmonised requirements must ensure road safety
throughout the whole Community;
HAS ADOPTED THIS DIRECTIVE:
Article 1
1. For the purposes of this Directive, ‘vehicle’ means any motor
vehicle falling within one of the international categorieslis ted belowand intended for use on the road, such vehicle being with or withoutbodywork, having at least four wheels and a maximum design speedexceeding 25 km/h, and itstrailers , with the exception of vehicles
which run on rails, agricultural tractors and machinery and public
worksvehicles :
(a) Category M: Motor vehicleshaving at leas t four wheelsor having
three wheelswhen the maximum weight exceeds1 metric ton, and
used for the carriage of passengers:
— Category M
1: Vehicles used for the carriage of passengers, and
comprising not more than eight seats in additionto the driver'ss eat;
— Category M
2: Vehicles used for the carriage of passengers,
comprising more than eight seats in addition to
the driver'ss eat, and having a maximum weight
not exceeding 5 metric tons;
— Category M3: Vehicles used for the carriage of passengers,
comprising more than eight seats in addition tothe driver'ss eat, and having a maximum weightexceeding 5 metric tons.1971L0320 — EN — 03.01.1986 — 005.001 — 2
(1) OJ No C 160, 18.12.1969, p. 7.
(2) OJ No C 100, 1.8.1969, p. 13.
(3) OJ No L 42, 23.2.1970, p. 1.
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(b) Category N: Motor vehicleshaving at leas t four wheelsor having
three wheelswhen the maximum weight exceeds1 metric ton, andused for the carriage of goods:
— Category N
1: Vehiclesus ed for the carriage of goodsand
having a maximum weight not exceeding 3·5metric tons;
— Category N
2: Vehiclesus ed for the carriage of goodsand
having a maximum weight exceeding 3·5 but
not exceeding 12 metric tons;
— Category N3: Vehiclesus ed for the carriage of goodsand
having a maximum weight exceeding 12 metrictons.
(c) Category O: Trailers (including semi-trailers):
— Category O
1: Trailerswith a maximum weight not exceeding
0·75 metric tons;
— Category O2: Trailerswith a maximum weight exceeding 0·75
but not exceeding 3·5 metric tons;
— Category O3: Trailerswith a maximum weight exceeding 3·5
but not exceeding 10 metric tons;
— Category O4: Trailerswith a maximum weight exceeding 10
metric tons.
2. Articulated category M vehiclesmade up of two non-s eparable
but articulated units shall be considered to be single vehicles.
3. In the case of a category M or N drawing vehicle designed to be
coupled to a semi-trailer, the maximum weight to be taken into consid-eration when classifying that vehicle shall be the weight of the drawingvehicle in running order plusthe maximum weight trans ferred to thedrawing vehicle by the semi-trailer and, where appropriate, the
maximum weight of the drawing vehicle'sown load.
4. In the case of category N vehicles, the equipment and fittings of
certain special vehicles not intended for the carriage of passengers
(such as crane vehicles, workshop vehicles, publicity vehicles) shall
be considered to be goods.
5. The maximum weight to be taken into consideration when classi-
fying a category O semi-trailer shall be the weight transmitted to the
ground by the axle or axlesof the s emi-trailer when coupled to the
drawing vehicle and laden with a maximum load.
Article 2
No Member State may refuse to grant EEC type-approval or national
type-approval of a vehicle on groundsrelating to itsbraking device ifthat vehicle isfitted with the devicess pecified in AnnexesI to VIII andX to XII and if these devices satisfy the requirements set out therein.
Article 2a
No Member State may refuse or prohibit the sale, registration, entry
into service or use of a vehicle on grounds relating to its brakingdevicesif that vehicle isequipped with the braking devicess pecifiedin Annexes I to VIII and if such braking devices satisfy the require-mentss et out therein.1971L0320 — EN — 03.01.1986 — 005.001 — 3
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Article 3
The Member State which hasgranted type approval s hall take the
necessary measures to ensure that it is informed of any modification
to a component or characteristic mentioned in item 1.1 of Annex I.
The competent authoritiesof that State s hall decide whether the modi-fied prototype should be submitted to fresh tests and whether a freshreport should be drawn up thereon. If such tests reveal failure tocomply with the requirementsof thisDirective, the modification s hallnot be authorised.
Article 4
Pending the entry into force of a separate Directive on the definition of
an ‘urban bus’, such vehicles shall continue to be submitted to the
Type II A test described in Annex II where their maximum weight
exceeds10 metric tons .
Article 5
The amendments necessary for adjusting the requirements of the
Annexes so as to take account of technical progress shall be adoptedin accordance with the procedure laid down in Article 13 of theCouncil Directive of 6 February 1970 on the type approval of motorvehiclesand their trailers .
Article 6
1. Member States shall put into force the provisions containing the
requirementsneeded in order to comply with thisDirective within
eighteen monthsof itsnotification and s hall forthwith inform the
Commission thereof.
2. With effect from 1 October 1974, the provisions of item 2.2.1.4
of Annex I shall also apply to vehicles other than those in categoryM
3or category N3.
3. Member States shall ensure that the texts of the main provisions
of national law which they adopt in the field covered by thisDirective
are communicated to the Commission.
Article 7
This Directive is addressed to the Member States.1971L0320 — EN — 03.01.1986 — 005.001 — 4
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ANNEX I
DEFINITIONS,REQUIREMENTS,CONSTRUCTIONANDFITTING
1. DEFINITIONS
For the purpose of this Directive:
1.1.‘Typeofvehiclewithrespecttothebrakingdevices’
‘Type of vehicle with respect to the braking devices’ means vehicles
which do not differ in such essential respects as:
1.1.1.In the case of motor vehicles
1.1.1.1. the vehicle category, asdefined in Article 1 of this
Directive
1.1.1.2. the ►M3maximum mass ◄, asdefined in item 1.14
1.1.1.3. the distribution of ►M3mass◄among the axles
1.1.1.4. the maximum design speed1.1.1.5. a different type of braking device with particular refer-
ence to the presence or otherwise of devices for
braking a trailer
1.1.1.6. the number and arrangement of the axles1.1.1.7. the engine type1.1.1.8. the number and ratiosof gears1.1.1.9. ratio(s) of rear drive axle(s)1.1.1.10. the tyre dimensions
1.1.2.In the case of trailers
1.1.2.1. the vehicle category, asdefined in Article 1 of this
Directive
1.1.2.2. the ►
M3maximum mass ◄, asdefined in item 1.14
1.1.2.3. the distribution of ►M3mass◄among the axles
1.1.2.4. a different type of braking device1.1.2.5. the number and arrangement of the axles1.1.2.6. the tyre dimensions
1.2.‘Brakingdevice’
‘Braking device’ meansthe combination of partswhos e function is
progressively to reduce the speed of a moving vehicle or to bring it to
a halt, or to keep it stationary if it is already halted. These functions
are specified in item 2.1.2. The device shall consist of the brake
control, the transmission and the brake proper.
1.3.‘Graduatedbraking’
‘Graduated braking’ meansbraking during which, within the normal
range of operation of the device, during either the application or the
releasing of the brakes,
— the driver can, at any time, increase or reduce the braking force
through action on the control,
— the braking force actsin the s ame direction asthe action on the
control (monotonic function),
— it is easily possible to make a sufficiently fine adjustment to the
braking force.
1.4.‘Control’
‘Control’ meansthe part actuated directly by the driver (or, where
appropriate, in the case of a trailer, the driver's mate) to supply to the
transmission the energy required for braking or controlling it. This1971L0320 — EN — 03.01.1986 — 005.001 — 5
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energy may be the muscular energy of the driver, or energy from
another source controlled by the driver, or in appropriate cases the
kinetic energy of a trailer, or a combination of these various kinds of
energy.
1.5.‘Transmission’
‘Transmission’ means the combination of components situated between
the control and the brake and connecting the two operationally. The
transmission may be mechanical, hydraulic, pneumatic, electrical, or
mixed. Where the braking power is derived from or assisted by a
source of energy independent of the driver but controlled by him, the
reserve of energy in the device shall likewise be regarded as part of the
transmission.
1.6.‘Brake’
‘Brake’ meansthe part in which the forcesoppos ing the movement of
the vehicle develop. It may be a friction brake (when the forcesare
generated by the friction between two partsof the vehicle moving rela-
tively to one another); an electrical brake (when the forcesare
generated by electromagnetic action between two partsof the vehicle
moving relatively to but not in contact with one another); a fluid brake
(when the forcesare generated by the action of a fluid s ituated between
two partsof the vehicle moving relatively to one another); or an engine
brake (when the forcesare derived from a controlled increas e in the
braking action of the engine transmitted to the wheels).
1.7.‘Differenttypesofbrakingdevices’
‘Different typesof braking devices ’ meansequipment which differsin
such essential respects as:
1.7.1. components having different characteristics,
1.7.2. a component made of materialshaving different characteris tics
or a component different in shape or size,
1.7.3. a different assembly of the components.
1.8.‘Brakingsystemcomponent’
‘Braking system component’ means one of the individual parts which,
when assembled, constitute the braking device.
1.9.‘Continuousbraking’
‘Continuousbraking’ meansthe braking of combinationsof vehicles
through an installation having the following characteristics:
1.9.1. a single control which the driver actuates progressively, by a
single movement, from his driving seat,
1.9.2. the energy used for braking the vehicles constituting the combi-
nation of vehicles is supplied from the same source (which may
be the muscular energy of the driver),
1.9.3. the braking installation ensures simultaneous or suitably phased
braking of each of the constituent vehicles of the combination,
whatever their relative positions.
1.10.‘Semi-continuousbraking’
‘Semi-continuousbraking’ meansthe braking of combinationsof vehi-
cles through an installation having the following characteristics:
1.10.1. a single control which the driver can actuate progressively, by
a single movement, from his driving seat,
1.10.2. the energy used for braking the vehicles constituting the
combination of vehicles is supplied from two different sources
(one of which may be the muscular energy of the driver),
1.10.3. the braking installation ensures simultaneous or suitably phased
braking of each of the constituent vehicles of the combination,
whatever their relative positions.1971L0320 — EN — 03.01.1986 — 005.001 — 6
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1.11.‘Automaticbraking’
‘Automatic braking’ meansbraking of the trailer or trailersoccurring
automatically in the event of separation of components of the combina-
tion of coupled vehicles, including such separation through coupling
breakage, without the effectiveness of the remainder of the combina-
tion being affected.
1.12.‘Inertiaor“overrun”braking’
‘Inertia braking’ meansbraking by utilis ing the forcesgenerated by the
trailer'smoving up on the drawing vehicle.
1.13.‘Ladenvehicle’
‘Laden vehicle’ means, except where otherwise stated, a vehicle laden
to its‘►M3maximum mass ◄’.
1.14.‘►M3 Maximummass ◄’
‘►M3Maximum mass ◄’ meansthe ►M3maximum mass ◄
stated by the vehicle manufacturer to be technically permissible (this
►M3mass◄may be higher than the ‘permissible ►M3maximum
mass◄’).
1.15.‘Hydraulicbrakingdevicewithstoredenergy’
‘Hydraulic braking device with stored energy’ means a braking system
where energy is supplied by a hydraulic fluid under pressure, stored in
one or more accumulators fed from one or more pressure pumps each
fitted with a means of limiting the pressure to a maximum value. This
value shall be specified by the manufacturer.
1.16.‘CategoryO3andO4trailer types’
1.16.1.‘Semi-trailer’
‘Semi-trailer’ meansa towed vehicle in which the axle(s ) is
(are) positioned behind the centre of gravity of the vehicle
(when uniformly loaded) and which isequipped with a
connecting device permitting horizontal and vertical forcesto
be transmitted to the drawing vehicle.
1.16.2.‘Full trailer’
‘Full trailer’ means a towed vehicle having at least two axles,
and equipped with a towing device which can move vertically
(in relation to the trailer) and controlsthe direction of the front
axle(s), but which transmits no significant static load to the
drawing vehicle.
1.16.3.‘Centre-axle trailer’
‘Centre-axle trailer’ meansa towed vehicle equipped with a
towing device which cannot move vertically (in relation to the
trailer), and in which the axle(s) is (are) positioned close to the
centre of gravity of the vehicle (when uniformly loaded) such
that only a small static vertical load, not exceeding 10 % of the
maximum mass of the trailer or 1 000 kg (whichever is the
lesser) is transmitted to the drawing vehicle.
The maximum mass to be taken into consideration when clas-
sifying a centre-axle trailer shall be the mass transmitted to the
ground by the axle(s) of the centre-axle trailer when coupled to
the drawing vehicle and laden with a maximum load.
1.17.‘Retarder’ (1)
‘Retarder’ means an additional braking system having the capability to
provide and to maintain a braking effect over a long period of time
without a significant reduction in performance. The term ‘retarder’
covers the complete system including the control device.1971L0320 — EN — 03.01.1986 — 005.001 — 7
(1) Until uniform procedureshave been agreed to calculate the effectsof retarderson the
provisions in the Appendix to item 1.1.4.2 of Annex II, this definition does not cover
vehicles fitted with regenerative braking systems.▼M4
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1.17.1.‘Independent retarder’
‘Independent retarder’ meansa retarder whos e control device is
separate from that of the service and other braking systems.
1.17.2.‘Integrated retarder’ (1)
‘Integrated retarder’ meansa retarder whos e control device is
integrated with that of the service braking system in such a
way that both retarder and service braking systems are applied
simultaneously or suitably phased by operation of the
combined control device.
1.17.3.‘Combined retarder’
‘Combined retarder’ meansan integrated retarder which in
addition hasa cut-out device, which allowsthe combined
control to apply the service braking system alone.
2. CONSTRUCTION AND FITTING REQUIREMENTS
2.1.General
2.1.1.Braking device
2.1.1.1. The braking device must be so designed, constructed and
fitted as to enable the vehicle in normal use, despite the
vibration to which it may be subjected, to comply with
the undermentioned requirements.
2.1.1.2. In particular, the braking device must be so designed,
constructed and fitted as to be able to resist the corrosion
and ageing phenomena to which it isexpos ed.
2.1.2.Functions of the braking device
The braking device defined in item 1.2 must fulfil the following
conditions:
2.1.2.1. Service braking
The service braking must enable the driver to control the
movement of the vehicle and to halt it safely, speedily
and effectively, whatever itss peed and load, on any up
or down gradient. It must be possible to graduate this
braking action. The driver must be able to achieve this
braking action from hisdriving s eat without removing
hishandsfrom the s teering control.
2.1.2.2. Secondary braking
The secondary braking must make it possible to halt the
vehicle within a reasonable distance in the event of the
failure of the service braking. It must be possible to
graduate thisbraking action. The driver mus t be able to
obtain thisbraking action from hisdriving s eat while
keeping at least one hand on the steering control. For
the purposes of these requirements, it is assumed that
not more than one failure of the service braking can
occur at one time.
2.1.2.3. Parking braking
The parking braking must enable the vehicle to be held
stationary on an up or down gradient even in the absence
of the driver, the working partsbeing then held in the
locked position by a purely mechanical device. The
driver must be able to achieve this braking action fromhis driving seat, subject, in the case of a trailer, to the
requirementsof item 2.2.2.10.1971L0320 — EN — 03.01.1986 — 005.001 — 8
(1) Until uniform procedureshave been agreed to calculate the effectsof retarderson the
provisions in the Appendix to item 1.1.4.2 of Annex II, vehicles equipped with an inte-grated retarder must also be equipped with an anti-lock device, acting on at least theservice brakes of the axle controlled by the retarder, and on the retarder, and complying
with the requirementss pecified in Annex X.▼B
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2.1.3.Pneumatic connections between motor vehicles and trailers
2.1.3.1. In the case of a braking device operated by compressed
air, the pneumatic link with the trailer must be of the
type with two or more lines. However, in all cases, all
the requirements of this Directive must be satisfied by
the use of only two lines. Shut-off devices which are
not automatically actuated shall not be permitted. In the
case of articulated vehicle combinations, the flexible
hoses shall be a part of the drawing vehicle. In all other
cases, the flexible hoses shall be a part of the trailer.
2.2.Characteristics ofbrakingdevices
2.2.1.Vehicles of categories M and N
2.2.1.1. The set of braking devices with which a vehicle is
equipped must satisfy the requirements laid down for
the service, secondary and parking brake
2.2.1.2. The devices providing service, secondary and parking
braking may have common components, provided that
they fulfil the following conditions:
2.2.1.2.1. there must be at least two controls, indepen-
dent of each other and readily accessible to
the driver from hisnormal driving pos ition.
For all categoriesof vehicles , except M2and
M3, every brake control (excluding a retarder
control) shall be designed such that it returns
to the fully-off position when released. This
requirement shall not apply to a parking
brake control (or that part of a combined
control) when it ismechanically locked in
an applied position;
2.2.1.2.2. the control of the service braking device must
be independent of the control of the parking
braking device;
2.2.1.2.3. where the service and secondary braking
deviceshave the s ame control, the effective-
ness of the linkage between that control and
the various components of the transmission
systems must not be liable to diminish after
a certain period of use;
2.2.1.2.4. where the service and secondary braking
deviceshave the s ame control, the parking
braking device must be so designed that it
can be actuated when the vehicle isin
motion. ►M3This provision shall not apply
where an auxiliary control permitsat leas t
partial actuation of the service braking
system, as provided for in Annex II, item
2.1.3.6; ◄
2.2.1.2.5. in the event of a breakage of any component
other than the brakes(asdefined in item 1.6)
or the componentss pecified in item 2.2.1.2.7,
or of any other failure of the service braking
device (malfunction, partial or total exhaus-
tion of an energy reserve), the secondary
braking device or that part of the service
braking device which isnot affected by the
failure must be able to bring the vehicle to a
halt in the conditionspres cribed for
secondary braking;
2.2.1.2.6. in particular, where the secondary braking
device and the service braking device have a
common control and common transmission;
2.2.1.2.6.1. where the service braking is
actuated by the muscular energy
of the driver assisted by one or
more energy reserves, the
secondary braking must, in the1971L0320 — EN — 03.01.1986 — 005.001 — 9
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event of failure of that assistance,
be capable of being ensured by
the muscular energy of the driver
assisted by the energy reserves, if
any, which are unaffected by the
failure, the force applied to the
control not exceeding the
prescribed maxima;
2.2.1.2.6.2. where the force for the service
braking and transmission depend
exclusively on the use of an
energy reserve controlled by the
driver, there must be at least two
completely independent energy
reserves, each provided with its
own independent transmission;
each of them may act on the
brakesof only two or more
wheels so selected as to be
capable of ensuring by them-
selves the prescribed degree of
secondary braking without
endangering the stability of the
vehicle during braking; in addi-
tion, each of these energy
reserves must be fitted with a
warning device asdefined in
item 2.2.1.13;
2.2.1.2.7. certain parts, such as the pedal and its
bearing, the master cylinder and its piston(s)
(hydraulic systems), the control valve
(hydraulic and/or pneumatic systems), the
linkage between the pedal and the master
cylinder or the control valve, the brake cylin-
dersand their pis tons(hydraulic and/or
pneumatic systems), and the lever-and-cam
assemblies of brakes, shall not be regarded
asliable to breakage if they are amply
dimensioned, are readily accessible for main-
tenance, and exhibit safety features at least
equal to those prescribed for other essential
components (such as the steering linkage) of
the vehicle. Where the failure of any such
part would make it impossible to brake the
vehicle with a performance at least equal to
that prescribed for the secondary braking,
that part must be made of metal or of a mate-
rial with equivalent characteristics and must
not be subject to significant distortion in the
normal operation of the braking devices.
2.2.1.3. Where there are separate controls for the service and
secondary braking devices, simultaneous actuation of
the two controls must not render both the service and
secondary braking devices inoperative, either when
both braking devicesare in good working order or
when one of them isfaulty.
2.2.1.4. In the event of failure in a part of the transmission of
the service brake, the following conditions must be met:
2.2.1.4.1. a sufficient number of wheels must still be
braked by actuation of the service braking
device control, whatever the vehicle load;
2.2.1.4.2. these wheels must be so selected that the
residual performance of the service braking
device satisfies the requirements laid down
in item 2.1.4 of Annex II;
2.2.1.4.3. however, the above requirementss hall not
apply to drawing vehiclesfor s emi-trailers
when the transmission of the service braking1971L0320 — EN — 03.01.1986 — 005.001 — 10
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device of the semi-trailer is independent of
that of the drawing vehicle.
2.2.1.5. Where use is made of energy other than the muscular
energy of the driver, there need not be more than one
source of such other energy (hydraulic pump, air
compressor, etc.), but the means by which the device
constituting that source is driven must be as safe as
practicable.
2.2.1.5.1. In the event of failure in any part of the
transmission of a vehicle's braking devices,
the supply to the part not affected by the
failure must continue to be ensured where
thisisrequired for the purpos e ofhalting the
vehicle with the degree of effectiveness
prescribed for residual and/or for secondary
braking. Thiscondition mus t be met by
meansof deviceswhich can be eas ily actu-
ated when the vehicle iss tationary, or by
automatic means.
2.2.1.5.2. In addition, storage devices located down-
circuit of this device must be such that in
the event of a failure in the energy supply,
after four full-stroke actuations of the service
brake control under the conditionspres cribed
in item 1.2 of Annex IV it is still possible to
halt the vehicle at the fifth application with
the degree of effectiveness prescribed for
secondary braking.
2.2.1.5.3. However, for hydraulic braking deviceswith
stored energy, these provisions can be consid-
ered to be met, provided that the
requirementsof item 1.2.2 of Annex IV,
section C, are satisfied.
2.2.1.6. The requirementsof items2.2.1.2, 2.2.1.4 and 2.2.1.5
must be met without the use of any automatic device
of a kind such that its ineffectiveness might pass unno-
ticed because the parts which are normally in an ‘at
rest’ position are actuated only in the event of failure
of the braking device.
2.2.1.7. The service braking device must act on all the wheels
on the vehicle.
2.2.1.8. The action of the service braking device must be appro-
priately distributed among the axles.
2.2.1.9. The action of the service braking device must be
distributed between the wheels of the same axle
symmetrically in relation to the longitudinal median
plane of the vehicle.
2.2.1.10. The service braking device and the parking braking
device must act on braking surfaces permanently
connected to the wheelsthrough componentsof
adequate strength. It must not be possible to disconnect
a braking surface from the wheels; however, in the case
of the servicing device and secondary braking device,
such disconnection of the braking surfaces shall be
permitted provided that it isonly momentary, for
instance during a change of gear, and that both the
service braking and the secondary braking continue to
operate with the prescribed degree of effectiveness. In
addition, any such disconnection shall be permitted in
the case of the parking braking device, provided that it
iscontrolled exclus ively by the driver from hisdriving
seat by a system which cannot be actuated by a leak(1).1971L0320 — EN — 03.01.1986 — 005.001 — 11
(1) This item must be interpreted in the following way: The performance of the service and
secondary braking devices must remain within the limits prescribed in the Directive,
even during momentary disconnection.▼M4
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2.2.1.11. Wear on the brakes must be easily compensated by
means of a system of manual or automatic adjustment.
In addition, the control and the componentsof the
transmission and of the brakes must possess a reserve
of travel and, if necessary, suitable means of compensa-
tion such that, when the brakes become heated or when
the brake liningshave reached a certain degree of wear,
effective braking is ensured without immediate adjust-
ment being necessary.
2.2.1.12. In hydraulic braking devices:
2.2.1.12.1. the filling ports of the fluid reservoirs must
be readily accessible; in addition, the
containers of reserve fluid must be so made
that the level of the reserve fluid can be
easily checked without the containers
having to be opened. Where thislas t condi-
tion isnot fulfilled, a warning light mus t
indicate to the driver when the reserve fluid
fallsto a level liable to caus e a failure of
the braking device. The driver must be able
to check easily whether the light is func-
tioning properly;
2.2.1.12.2. the failure of a part of a hydraulic transmis-
sion system shall be signalled to the driver
by a device comprising a red tell-tale lamp
lighting up not later than on actuation of
the control and remaining lit aslong asthe
failure persists and the ignition (start) switch
isin the ‘on’ (run) pos ition. However a
device comprising a red tell-tale lamp
lighting up when the level of the fluid in
its reservoirs falls below the value specified
by the manufacturer is admissible. The tell-
tale lamp shall be visible even by daylight;
the satisfactory condition of the lamp mustbe easily verifiable by the driver from the
driver'ss eat. The failure of a component of
the device shall not entail total loss of effec-
tiveness of the braking device in question.
2.2.1.13. Any vehicle fitted with a service brake actuated by an
energy reservoir must, where the prescribed secondary
braking performance cannot be obtained by meansof
this brake without the use of stored energy, be provided
with a warning device — in addition to a pressure
gauge, where fitted — giving an optical or acoustic
signal when the stored energy in any part of the system
fallsto a value at which, without recharging of thereservoir and irrespective of the load conditions of the
vehicle, it is possible to apply the service brake control
a fifth time after four full-stroke actuations and obtain
the prescribed secondary braking performance (without
faults in the service-brake transmission device and
with the brakes adjusted as closely as possible). The
warning device must be directly and permanently
connected to the circuit. When the engine isrunning
under normal operating conditionsand there are no
faults in the braking system, the warning device must
give no signal except during the time required for char-
ging the energy reservoir(s) after start-up of the engine.
2.2.1.13.1. However, in the case of vehicles which are
only considered to comply with the require-
mentsof item 2.2.1.5.1 by virtue of meeting
the requirementsof item 1.2.2 of Annex IV,
section C, the alarm device shall consist of
an acoustic signal in addition to an optical
signal. These devices need not operate
simultaneously, provided that each of them
meetsthe above requirementsand the
acoustic signal is not actuated before the
optical signal.1971L0320 — EN — 03.01.1986 — 005.001 — 12
▼B
▼M4
▼M3
▼M4
▼M4
2.2.1.13.2. Thisacous tic device may be rendered inop-
erative while the handbrake isapplied and/
or, at the choice of the manufacturer, in the
case of automatic transmission the selector
isin the ‘park’ pos ition.
2.2.1.14. Without prejudice to the requirementsof item 2.1.2.3,
where the use of an auxiliary energy source is essential
for the operation of a braking device, the energy reserve
must be such as to ensure that, should the engine stop,
or in the event of a failure of the meansby which the
energy source is driven, the braking performance
remainss ufficient to bring the vehicle to a halt in the
prescribed conditions. In addition, if the muscular
energy applied by the driver to the parking brake device
isreinforced by s ome aid, the actuation of the parking
braking must be ensured in the event of failure of that
aid, if necessary a reserve of energy independent of that
normally supplying such aid. This reserve of energy
may be that indended for the service braking. The
expression ‘actuation’ also covers the action of
releasing.
2.2.1.15. In the case of a motor vehicle to which the coupling of
a trailer equipped with a brake controlled by the driver
of the drawing vehicle is authorised, the service braking
device of the drawing vehicle must be fitted with a
device so designed that if the trailer braking device
should fail, or the air supply pipe (or such other type
of connection asmay be adopted) between the drawing
vehicle and trailer should break, it will still be possible
to brake the drawing vehicle with the effectiveness
prescribed for the secondary braking; it is accordingly
prescribed, in particular, that this device be fitted to
the drawing vehicle(1).
2.2.1.16. The auxiliary equipment must draw its energy only in
such a way that its operation, even in the event of
damage to the energy source, cannot cause the reserves
of energy feeding the braking devicesto fall below the
level indicated in item 2.2.1.13.
►M42.2.1.17. ◄Where the trailer belongsto category O3or
O4, the service braking device must be of a continuous
or semi-continuous type.
►M42.2.1.18. ◄In the case of a vehicle authorised to draw a
category O3or O4trailer, the braking devicesmus t
satisfy the following conditions:
►M42.2.1.18.1. ◄when the secondary braking
device of the drawing vehicle isactuated,
there must also be a graduated braking
action on the trailer;
►M42.2.1.18.2. ◄should the main braking device
of the drawing vehicle fail, and if this
device ismade up of at leas t two indepen-
dent sections, the section or sections not
affected by thisfailure mus t be able
partially or fully to actuate the trailer
brakes. It must be possible to graduate this
braking action. ►M3If thisoperation is
achieved by a valve which isnormally at
rest, then such a valve may only be incorpo-
rated if itscorrect functioning can eas ily be
checked by the driver, either from within
the cab or from outside the vehicle, without
the use of tools; ◄1971L0320 — EN — 03.01.1986 — 005.001 — 13
(1) This point is to be interpreted in the following way: It is essential, in all cases, that the
service braking device should be fitted with a device (for instance a limiting valve)ensuring that the vehicle can still be braked by the service brake, but with a perfor-
mance equal to that of the secondary brake.▼B
▼M4
▼B
▼B
►M42.2.1.18.3. ◄in the case of a break or leak in
one of the air supply pipes (or in such other
type of connection asmay be adopted), it
must nevertheless be possible for the driver
to fully or partially actuate the trailer
brakes, by means either of the service
braking control or of the secondary braking
control or of a separate control, unless the
break or leak automatically causes the
trailer to be braked;
2.2.1.18.4. in the case of a two-line air supply system,
the requirement in item 2.2.1.18.3 above
shall be considered to be met if the
following conditionsare fulfilled:
2.2.1.18.4.1. when the service brake control
of the drawing vehicle isfully
actuated, the pressure in the
supply line must fall to 1,5
bar within the following two
seconds;
2.2.1.18.2. when the supply line is evacu-
ated at the rate of at least 1
barsthe automatic braking of
the trailer must operate when
the pressure in the supply line
fallsto 2 bar.
►M42.2.1.19. ◄Except in the case of ‘urban buses’, vehicles
used for the carriage of passengers comprising more
than eight seats in addition to the driver's seat, and
having a ►M3maximum mass ◄exceeding 10
metric tons, must satisfy the Type II A test described
in item 1.5 of Annex II and not the Type II test
described in item 1.4 of that Annex.
2.2.1.20. In the case of a motor vehicle equipped to draw a trailer
with electric service brakes, the following requirements
shall be met:
2.2.1.20.1. the power supply (generator and battery) of
the motor vehicle shall have a sufficient
capacity to provide the current for an elec-
tric braking system. With the engine
running at the idling speed recommended
by the manufacturer and all electric devices
supplied by the manufacturer as standard
equipment of the vehicle switched on, the
voltage in the electrical liness hall at
maximum current consumption of the elec-
tric braking system (15 A) not fall below
the value of 9,6 V measured at the connec-
tion. The electrical liness hall not be
capable of short-circuiting even when over-
loaded;
2.2.1.20.2. in the event of a failure of the drawing vehi-
cle'ss ervice braking device, where that
device consists of at least two independent
units, the unit or units not affected by the
failure shall be capable of partially or fully
actuating the brakesof the trailer;
2.2.1.20.3. the use of the stop-light switch and circuit
for actuating the electric braking system is
permissible only if the actuating line is
connected in parallel with the stop-light
and the existing stop-light switch and circuit
are capable of taking the extra load.
2.2.1.21. In the case of a pneumatic service braking device
comprising two or more independent sections, any
leakage between those sections at or downstream of
the control shall be continuously vented to atmosphere.1971L0320 — EN — 03.01.1986 — 005.001 — 14
▼M4
▼B
▼M4
▼B
2.2.2.Vehicles of category O
2.2.2.1. Trailersof category O1need not be fitted with a service
braking device; however, if trailersof thiscategory are
equipped with a service braking device this must
comply with the same requirements as those of category
O2.
2.2.2.2. Every trailer of category O2must be fitted with a
service braking device either of the continuous or
semi-continuous type or of the inertia (overrun) type.
The latter type shall be authorized only for trailers other
than semi-trailers. However, electric service brakes
conforming to the requirementsof Annex XI s hall be
permitted.
2.2.2.3. Every trailer of category O3or O4must be fitted with a
service braking device of the continuous or semi-contin-
uoustype.
2.2.2.4. The service braking device must act on all the wheels
of the trailer.
2.2.2.5. The action of the service braking device must be
suitably distributed among the axles.
2.2.2.6. The action of every braking device must be distributed
between the wheelsof each axle s ymmetrically in rela-
tion to the longitudinal median plane of the vehicle.
2.2.2.7. The braking surfaces required to attain the prescribed
degree of effectiveness must be in constant contact
with the wheels, either rigidly or through components
not liable to failure.
2.2.2.8. Wear on the brakes must be easily compensated by a
system of manual or automatic adjustment. In addition,
the control and the components of the transmission and
of the brakes must possess a reserve of travel and ifnecessary, suitable means of compensation such that,
when the brakesbecome heated or when the brake
liningshave reached a certain degree of wear, effective
braking is ensured without immediate adjustment being
necessary.
2.2.2.9. The braking devices must be such that the trailer is
stopped automatically if the coupling breaks while the
trailer isin motion. However, thisrequirement s hall
not apply to single-axled trailers with a
►
M3maximum mass ◄not exceeding 1·5 metric
tonsprovided that the trailersare fitted, in addition to
the main coupling, with a secondary coupling (chain,
cable, etc.) which, in the event of breakage of the
main coupling, can stop the drawbar from touching the
ground and provide some residual steering action on the
trailer.
2.2.2.10. On every trailer which isrequired to be fitted with a
service braking device, parking braking must be
ensured even when the trailer is separated from the
drawing vehicle. It must be possible for a person
standing on the ground to actuate the parking braking
device; however, in the case of a trailer used for the
carriage of passengers, it must be possible to actuate
this brake from inside the trailer. The expression
‘actuate’ also covers the action of releasing.
2.2.2.11. Where a trailer isfitted with a device enabling
compressed-air actuation of the braking device to be
cut out, the first-mentioned device must be so designed
and constructed that it is positively restored to the ‘at
rest’ position not later than on the resumption of the
supply of compressed air to the trailer.1971L0320 — EN — 03.01.1986 — 005.001 — 15
▼M4
▼B
▼M4
▼B
▼M4
2.2.2.12. Trailersof categoriesO3and O4fitted with a two-line
air supply system shall satisfy the conditions specified
in item 2.2.1.18.4 above.1971L0320 — EN — 03.01.1986 — 005.001 — 16
▼B
ANNEX II
BRAKINGTESTSANDPERFORMANCEOFBRAKINGDEVICES
1. BRAKING TESTS
1.1.General
1.1.1. The performance prescribed for braking devices shall be based on
the stopping distance. The performance of a braking device shall
be determined either by measuring the stopping distance in rela-
tion to the initial speed or by measuring the reaction time of the
device and the mean deceleration in normal operation as
prescribed in Annex III.
1.1.2. The stopping distance shall be the distance covered by the vehicle
from the moment when the driver beginsto actuate the control of
the device until the moment when the vehicle stops; the initial
speed shall be the speed at the moment when the driver begins
to actuate the control of the device. In the formulae given below,
for the measurement of braking performance,
v = initial speed in km/h
s = stopping distance in metres.
1.1.3. For the type approval of any vehicle, the braking performance
shall be measured during road tests conducted in the following
conditions:
1.1.3.1. the vehicle'scondition asregards ►M3mass◄must
be as prescribed for each type of test and be specified
in the test report;
1.1.3.2. the test must be carried out at the speeds prescribed for
each type of test. Where a vehicle is so constructed that
its maximum speed is lower than that prescribed for a
test, the test must be performed at the maximum speed
of the vehicle;
1.1.3.3. during the tests the force applied to the brake control in
order to obtain the prescribed performance must not
exceed the maximum laid down for the test vehicle's
category;
1.1.3.4. ►M2without prejudice to the requirementscontained in
item 1.1.4.2 below, the road shall possess a surface
having good adhesion; ◄
1.1.3.5. the tests must be performed when there is no wind liable
to affect the results;
1.1.3.6. at the start of the tests the tyres must be cold and at the
pressure prescribed for the load actually borne by the
wheelswhen the vehicle iss tationary;
1.1.3.7. the prescribed performance must be obtained without
locking of the wheels, without deviation of the vehicle
from itscours e, and without abnormal vibration.
1.1.4.Behaviour of the vehicle during braking
1.1.4.1. In braking tests, and in particular in those at high speed,
the general behaviour of the vehicle during braking must
be checked.
1.1.4.2. The behaviour of vehiclesin categoriesM1,M2,M3,N1,
N2,N3,O3and O4on a road surface having reduced adhe-
sion shall fulfil the conditions laid down in the
Appendix.1971L0320 — EN — 03.01.1986 — 005.001 — 17
▼M2
▼B
1.2.TypeOtest
(ordinary performance test with brakes cold)1.2.1.General
1.2.1.1. The brakesmus t be cold. A brake isdeemed to be cold
when the temperature measured on the disc or on the
outside of the drum is below 100ºC.
1.2.1.2. The test must be conducted in the following conditions:
1.2.1.2.1. the vehicle must be laden, the distribution of
its►
M3mass◄among the axlesbeing that
stated by the maker. Where provision is made
for several arrangements of the load on the
axlesthe dis tribution of the ►M3maximum
mass◄among the axles must be such that
the load on each axle isproportional to the
maximum permissible load for each axle.
►M4In the case of tractive units for semi-
trailers, the load may be re-positioned approxi-
mately half-way between the kingpin position
resulting from the above loading conditions
and the centreline of the rear axle(s); ◄
1.2.1.2.2. every text must be repeated on the unladen
vehicle. In the cae of a motor vehicle there
may be, in addition to the driver, a second
person on the front seat who is responsible
for noting the results of the test. In the case
of a motor vehicle designed to draw a semi-
trailer, the unladen tests will be conducted
with the vehicle in itss olo condition, including
a mass representing the fifth wheel. It will also
include a mass representing a spare wheel, if
this is included in the standard specification
of the vehicle. In the case of a vehicle
presented as a bare chassis-cab, a supplemen-
tary load may be added to simulate the mass
of the body, not exceeding the minimum mass
declared by the manufacturer in Annex IX;
1.2.1.2.3. the limitspres cribed for minimum perfor-
mance, both for tests with the vehicle unladen
and for tests with the vehicle laden, shall be
those laid down hereunder for each category
of vehicle;
1.2.1.2.4. the road must be level.
1.2.2.Type O test with engine disconnected
1.2.2.1. The test must be carried out at the speed prescribed for
the category to which the vehicle belongs, the figures
prescribed in this connection being subject to a certain
margin of tolerance. The minimum performance
prescribed for each category must be attained.
1.2.3.Type O test with engine connected
1.2.3.1. Apart from the test prescribed in item 1.2.2, additional
tests shall be carried out at various speeds with the
engine connected, the lowest being equal to 30 % of themaximum speed of the vehicle and the highest being
equal to 80 % of that speed. The maximum practical
performance figures shall be measured and the behaviour
of the vehicle shall be recorded in the test report. Trac-
tive units for semi-trailers, artificially loaded to simulate
the effects of a lade semi-trailer, shall not be tested
beyond 80 km/h.1971L0320 — EN — 03.01.1986 — 005.001 — 18
▼M4
▼B
▼M4
▼M4
1.2.4.Type O test for vehicles of category O equipped with compressed
air brakes
1.2.4.1. The braking performance of the trailer can be calculated
either from the braking rate of the drawing vehicle plus
the trailer and the measured thrust on the coupling or, in
certain cases, from the braking rate of the drawing
vehicle plusthe trailer with only the trailer being braked.
The engine of the drawing vehicle must be disconnected
during the braking test. In the case where only the trailer
isbraked, to take account of the extra mas sbeing
retarded, the performance will be taken to be the mean
fully developed deceleration.
1.2.4.2. With the exception of cases according to items 1.2.4.3
and 1.2.4.4, it is necessary for the determination of the
braking rate of the trailer to measure the braking rate of
the drawing vehicle plusthe trailer and the thrus t on the
coupling. The drawing vehicle must meet the require-
mentslaid down in the Appendix to item 1.1.4.2 of
Annex II with regard to the relation between the ratio
Tm
Pmand the pressure pm. The braking rate of the trailer
iscalculated according to the following formula:
zR¼zRþMþD
PR
where:
zR= braking rate of the trailer,
zR+M= braking rate of the drawing vehicle plusthe
trailer,
D = thrust on the coupling
(tractice force D = > 0)(compressive force D = < 0).
1.2.4.3. If a trailer hasa continuousor s emi-continuousbraking
device where the pressure in the brake actuators does
not change during braking despite the dynamic axle
load shifting, and in the case of semi-trailers, the trailer
alone may be braked. The braking rate of the trailer is
calculated according to the following formula:
z
R¼zRþM/C0R ðÞ /C1PMþPR
PRþR
where:
R = rolling resistance value = 0,01.
1.2.4.4. Alternatively, the evaluation of the braking rate of the
trailer may be done by braking the trailer alone. In this
case the pressure used shall be the same as that measured
in the brake actuatorsduring the braking of the combina-
tion.
1.3.TypeItest
(fade test)
1.3.1.With repeated braking
1.3.1.1. The service brakes of vehicles in categories M1,M2,M3,
N1,N2and N3shall be tested by successively applying
and releasing the brakes a number of times, the vehicle
being laden, in accordance with the conditionss hown in
the following table:
Conditions
Category
of vehiclev1
km/hv2
km/h∆t
secsn
M180% vmax-≤120½v145 15
M280% vmax-≤100½v155 151971L0320 — EN — 03.01.1986 — 005.001 — 19
▼B
▼B
Conditions
Category
of vehiclev1
km/hv2
km/h∆t
secsn
M380% vmax-≤60½v160 20
N180% vmax-≤120½v155 15
N280% vmax-≤60½v160 20
N380% vmax-≤60½v160 20
where:
v1= initial speed, when braking starts,
v2= speed at end of braking,
vmax= maximum speed of the vehicle,
n = number of timesbrakesapplied,∆t = duration of a braking cycle (time elapsing
between the initiation of one brake application
and the initiation of the next).
1.3.1.2. If the characteristics of the vehicle do not allow for the
period of time prescribed for ∆t, the duration may be
increased; in any event, in addition to the time necessary
for braking and accelerating the vehicle, a period of 10
seconds must be allowed in each cycle for stabilising
the speed v
1.
1.3.1.3. In these tests, the force applied to the control must be so
adjusted as to attain a mean deceleration of 3 m/sec2at
the first application of the brakes. This force must
remain constant throughout the succeeding brake applica-
tions.
1.3.1.4. During brake applicationsthe highes t gear ratio
(excluding overdrive, etc.) must be continuously
engaged.
1.3.1.5. For regaining speed after braking, the gearbox must be
used in such a way as to attain the speed v1in the
shortest possible time (maximum acceleration allowed
by the engine and gearbox).
1.3.2.With continuous braking
1.3.2.1. ►M3The service brakes of trailers of categories O2,O3and O4shall be tested in such a manner that ◄, the
vehicle being laden, the energy input to the brakesis
equivalent to that recorded in the same period of time
with a laden vehicle driven at a steady speed of 40 km/
h on a 7% down gradient for a distance of 1·7 km.
1.3.2.2. The test may be carried out on a level road, the trailer
being drawn by a motor vehicle; during the test, the
force applied to the control must be adjusted so as to
keep the resistance of the trailer constant (7% of the
►M3mass◄of the trailer). If the power available for
hauling is insufficient, the test can be conducted at a
lower speed but over a greater distance, as shown in the
following table:
Speed
(km/h)Distance
(metres)
40 1 700
30 1 950
20 2 500
15 3 1001971L0320 — EN — 03.01.1986 — 005.001 — 20
▼B
1.3.3.Residual performance
1.3.3.1. At the end of the Type I test (test described in item 1.3.1
or test described in item 1.3.2 of this Annex) the residual
performance of the service braking device shall be
measured under the same conditions (and in particular
at a constant control force no greater than the mean force
actually used) as for the Type O test with the engine
disconnected (the temperature conditions may be
different). For motor vehicles, this residual performance
must not be less than 80 % of that prescribed for the
category in question nor less than 60 % of the figure
recorded in the Type O test with the engine discon-
nected. However in the case of trailers, the residual
brake force at the periphery of the wheelswhen tes ted
at 40 km/h must not be less than 36 % of the force corre-
sponding to the maximum mass borne by the wheels
when the vehicle is stationary, nor less than 60 % of the
figure recorded in the Type O test at the same speed.
1.3.3.2. In the case of a motor vehicle which cannot comply with
the requirementsof item 1.3.3.1 above, a further hot
performance test may be carried out using a control force
not exceeding that specified in item 2.1.1.1 of this
Annex. The results of both tests shall be entered in the
report.
1.4.TypeIItest
(downhill behaviour test)
1.4.1. Laden vehicles shall be tested in such a manner that the energy
input isequivalent to that recorded in the s ame period of time
with a laden vehicle driven at an average speed of 30 km/h on a
6% down gradient for a distance of 6 km, with the appropriate
gear engaged (if the vehicle isa motor vehicle) and the retarder,
if the vehicle isfitted with one, being us ed. The gear engaged
must be such that the rpm of the engine does not exceed the
maximum value prescribed by the manufacturer.
1.4.2. For vehiclesin which the energy isabs orbed by the braking
action of the engine alone, a tolerance of ± 5 km/h on the average
speed shall be permitted, and the gear enabling the speed to be
stabilised at the value closest to 30 km/h on the 6% down
gradient shall be engaged. If the performance of the braking
action of the engine alone isdetermined by a meas urement of
deceleration, it shall be sufficient if the mean deceleration
measured is at least 0·5 m/sec2.
1.4.3. At the end of the test, the residual performance of the service
braking device shall be measured in the same conditions as for
the Type O test with the engine disconnected (the temperatureconditions, of course, are different). For motor vehicles, this resi-
dual performance must give a stopping distance not exceeding the
following values, using a control force not exceeding 700 N:
category M
30;15 V þ1;33 V2
130(the second term corresponding to a mean
braking deceleration of 3,75 m/s2);
category N30;15 V þ1;33 V2
115(the second term corresponding to a mean
braking deceleration of 3,3 m/s2).
However, in the case of trailers the residual brake force at the
periphery of the wheels when tested at 40 km/h must not be less
than 33 % of the force corresponding to the maximum mass
borne by the wheelswhen the vehicle iss tationary.
1.5.TypeIIAtest
(test for vehicles, other than ‘urban buses’, used for the carriage of
passengers comprising more than eight seats in addition to the driver's
seat and having a ►M3maximum mass ◄exceeding 10 metric tons)1971L0320 — EN — 03.01.1986 — 005.001 — 21
▼M4
▼B
▼M4
▼B
▼B
1.5.1. Laden vehicles shall be tested in such a manner that the energy
input isequivalent to that recorded in the s ame period of time
with a laden vehicle driven at an average speed of 30 km/h on a
7% down gradient for a distance of 6 km. During the test, the
service, secondary and parking braking devices must not be
engaged. The gear engaged must be such that the rpm of the
engine doesnot exceed the maximum value pres cribed by the
manufacturer. ►M4An integrated retarder may be used,
provided that it is suitably phased such that the service brakes
are not applied; thismay be verified by checking that thes e
brakesremain cold, asdefined in item 1.2.1.1 of thisAnnex. ◄
1.5.2. For vehiclesin which the energy isabs orbed by the braking
action of the engine alone, a tolerance of ± 5 km/h on the average
speed shall be permitted and the gear enabling the speed to be
stabilised at the value closest to 30 km/h on a 7% down gradient
shall be engaged. If the performance of the braking action of the
engine alone isdetermined by a meas urement of deceleration, it
shall be sufficient if the mean deceleration measured is at least
0·6 m/sec2.
2. PERFORMANCE OF BRAKING DEVICES
2.1.Vehiclesofcategories MandN
2.1.1.Service braking devices
2.1.1.1. Provisions relating to tests
2.1.1.1.1. The service brakes of vehicles of categories
M1,M2,M3,N1,N2and N3shall be tested
under the conditionss hown in the following
table:
M1M2M3N1N2N3
Type of
t e st O-I O-I O-I-I I O-I O-I O-I-I I
V 80 km/h 60 km/h 60 km/h 80 km/h 60 km/h 60 km/h
s≤ 0;1VþV2
1500;15VþV2
130
dm≥ 5,8 m/s25 m/s2
f≤ 500 N 700 N
where:
v = test speed
s = stopping distancedm = mean braking deceleration at normal
engine speed
f = force applied to foot control
2.1.2.Secondary braking devices
2.1.2.1. The secondary braking, even if the device which actuates
it is also used or other braking functions, must give a
stopping distance not exceeding the following values:
category M
10;1Vþ2V2
150(the second term corresponding to a
mean braking deceleration of 2,9 m/s2);
category M2,M30;15 V þ2V2
130(the second term corresponding to a
mean braking deceleration of 2,5 m/s2);
category N 0 ;15 V þ2V2
115(the second term corresponding to a
mean braking deceleration of 2,2 m/s2).1971L0320 — EN — 03.01.1986 — 005.001 — 22
▼M4
▼B
▼M4
▼B
2.1.2.2. If the secondary braking control is a manual control, the
prescribed performance must be obtained by applying to
the control a force not exceeding ►M3400 N◄in the
case of category M1vehiclesand ►M3600 N◄in the
case of other vehicles, and the control must be so placed
that it can be easily and quickly grasped by the driver.
2.1.2.3. If the secondary braking control is a foot control, the
prescribed performance must be obtained by applying to
the control a force not exceeding ►M3500 N◄in the
case of category M1vehiclesand ►M3700 N◄in the
case of other vehicles, and the control must be so placed
that it can be easily and quickly actuated by the driver.
2.1.2.4. The performance of the secondary braking device shall
be checked by the Type O test with the engine discon-
nected from the following initial speeds:
M1= 80 km/h
N1= 70 km/h
M2= 60 km/h
N2= 50 km/h
M3= 60 km/h;
N3= 40 km/h.
2.1.3.Parking braking devices
2.1.3.1. The parking braking device must, even if it is combined
with one of the other braking devices, be capable of
holding a laden vehicle stationary on an 18% up or
down gradient.
2.1.3.2. On vehiclesto which the coupling of a trailer is
authorised, the parking braking device of the drawing
vehicle must be capable of holding the combination of
vehicless tationary on a 12% gradient.
2.1.3.3. If the control isa manual control, the force applied to it
must not exceed ►M3400 N◄in the case of category
M1vehiclesand ►M3600 N◄in the case of all other
vehicles.
2.1.3.4. If it isa foot control, the force exerted on the control
must not exceed ►M3500 N◄in the case of category
M1vehiclesand ►M3700 N◄in the case of all other
vehicles.
2.1.3.5. A parking braking device which hasto be actuated
several times before attaining the prescribed performance
is admissible.
►M42.1.3.6. To check compliance with the requirementsof
Annex I, item 2.2.1.2.4, a Type O test must be carried
out with the engine disconnected at the initial speed
specified in item 2.1.2.4 for the relevant vehicle cate-
gory. The mean fully developed ◄deceleration on
application of either the parking brake or the auxiliary
control of the service brake, and the deceleration imme-
diately before the vehicle stops, shall be not less than
1·5 m/s2. The test shall be carried out with the vehicle
laden, and compliance with the requirementss hall be
deemed to be met if the braking performance hasbeen
achieved once. The force exerted on the braking control
shall not exceed the specified values. In the case of vehi-
clesof category M1or N1, fitted with a parking brake
using friction linings other than those for the service
braking system, the test may be carried out from 60 km/
h at the request of the manufacturer. In this case, the
mean fully-developed deceleration must be not less than
2·0 m/s2; deceleration immediately before the vehicle
stops must not be less than 1·5 m/s2.1971L0320 — EN — 03.01.1986 — 005.001 — 23
▼M4
▼B
▼M3
▼M4
2.1.4.Residual service braking after transmission failure
2.1.4.1. The residual performance of the service braking device,
in the event of failure in a part of its transmission, must
not be greater than the following stopping distances (or
less than the corresponding mean deceleration) using a
force applied to the control not exceeding 700 N, when
checked by the Type O test with the engine disconnected
from the following initial speeds for the relevent vehicle
category:
Stoppingdistance(m)andmeandeceleration (m/s2)
(km/h) Laden Unladen
M180 0 ;1Vþ100
30V2
150(1,7) 0 ;1Vþ100
25V2
150(1,5)
M260 0 ;15Vþ100
30V2
130(1,5) 0 ;15Vþ100
25V2
130(1,3)
M360 0 ;15Vþ100
30V2
130(1,5) 0 ;15Vþ100
30V2
130(1,5)
N170 0 ;15Vþ100
30V2
115(1,3) 0 ;15Vþ100
25V2
115(1,1)
N250 0 ;15Vþ100
30V2
115(1,3) 0 ;15Vþ100
25V2
115(1,1)
N340 0 ;15Vþ100
30V2
115(1,3) 0 ;15Vþ100
30V2
115(1,3)
2.2.Vehiclesofcategory O
2.2.1.Service braking devices
2.2.1.1. Requirement relating to tests of category O1vehicles.
2.2.1.1.1. Where the provision of a service braking
device ismandatory, the performance of the
device must meet the requirements laid down
for category O2.
2.2.1.2. Requirementsrelating to tes tsof category O2vehicles.
2.2.1.2.1. Where the trailer is fitted with compressed-air
brakes, the pressure in the control line and in
the forcesexerted at the periphery of the
braked wheels must be equal to not less than
X % of the force corresponding to the
maximum mass borne by the wheels when the
vehicle iss tationary, X having the following
values:
full trailer, laden and unladen 50,
semi-trailer, laden and unladen 45,
centre-axle trailer, laden and unladen 50.
Where the trailer is fitted with compressed-air
brakes, the pressure in the control line and in
the supply line must not exceed 6,5 bar(1)
during the brake test. The test speed is 60 km/
h. A supplementary test at 40 km/h must be
carried out with the laden vehicle for compar-
ison with the Type I test result.1971L0320 — EN — 03.01.1986 — 005.001 — 24
(1) The pressures specified here and in the following Annexes are relative pressures
measured in bars.▼B
▼M4
▼B
2.2.1.2.2. Where the braking device isof the inertia
type, it must comply with the conditions laid
down in Annex VIII.
2.2.1.2.3. In addition, these vehicles must be subjected
to the Type I test.
2.2.1.2.4. In the Type I test of a semi-trailer, the
►M3mass◄braked by itsaxlesmus t be
that corresponding to the load on the axle or
axlesof the s emi-trailer when the latter is
carrying itsmaximum load.
2.2.1.3. Requirementsrelating to the tes ting of category O3vehi-
cles. The same requirements apply as to category O2.
2.2.1.4. Requirementsrelating to tes tsof category O4vehicles.
2.2.1.4.1. The same requirements apply as apply to cate-
gory O2; in addition, these vehicles must be
subjected to the Type II test.
2.2.1.4.2. In the Type I and Type II tests of a semi-
trailer, the ►M3mass◄braked by itsaxles
must be that corresponding to the load on the
axle or axlesof the s emi-trailer when the latter
iscarrying itsmaximum load.
2.2.2.Parking braking devices
2.2.2.1. The parking brake with which the trailer or semi-trailer
isfitted mus t be capable of holding the laden trailer or
semi-trailer stationary, when separated from the drawing
vehicle, on an 18% up or down gradient. The force
applied to the control must not exceed ►M3600 N◄.
2.3.Reactiontime
Where a vehicle isfitted with a s ervice braking device which istotally
or partially dependent on a source of energy other than the muscular
effort of the driver, the following requirements must be satisfied:
2.3.1. in an emergency manoeuvre, the time clapsing between the
moment when the control beginsto be actuated and the moment
when the braking force on the least favourably placed axle
reaches the level corresponding to the prescribed performance
must not exceed 0·6 seconds;
2.3.2. in the case of vehicles fitted with compressed air braking devices,
the requirements of item 2.3.1 are considered to be satisfied if thevehicle complieswith the provis ionsof Annex III;
2.3.3. in the case of vehicles fitted with hydraulic braking devices, the
requirements of item 2.3.1 are considered to be satisfied if, in an
emergency manœuvre, the deceleration of the vehicle, or the
pressure at the least favourable brake cylinder, reaches a level
corresponding to the prescribed performance within 0,6 seconds.1971L0320 — EN — 03.01.1986 — 005.001 — 25
▼M3
▼B
▼M3
▼B
▼M3
▼M4
▼M1
Appendix (See 1.1.4.2)
DISTRIBUTIONOFBRAKINGEFFORTAMONGVEHICLEAXLES
1. GENERAL REQUIREMENTS
Vehiclesof categoriesM, N, O3and O4which are not equipped with
an anti-lock device asdefined in Annex X s hall meet all the require-
ments of this Appendix. If a special device is used, this must operate
automatically.
2. SYMBOLS
i = axle index (i = 1, front axle; i = 2, second axle; etc.)
Pi= normal reaction of road surface on axle i under static
conditions
Ni= normal reaction of road surface on axle i under braking
Ti= force exerted by the brakeson axle i under normal braking
conditionson the road
fi=Ti/Ni, adhesion used by axle i(1)
J = deceleration of vehicle
g = acceleration due to gravity g = 10 m/s2
z = braking rate of vehicle = J/g(2)
P= ►M3mass◄of vehicle
h = height of centre of gravity specified by the manufacturer
and agreed by the Technical Servicesconducting the
approval test
E = wheelbase
k = theoretical coefficient of adhesion between tyre and road
Kc= correction factor — semi-trailer laden
Kv= correction factor — semi-trailer unladen
TM = sum of braking forces at the periphery of wheels of
drawing vehiclesfor trailersor s emi-trailers
PM = total normal static reaction between road surface and
wheelsof drawing vehiclesfor trailer or s emi-trailer as
referred to in items3.1.4 and 3.1.5 res pectively
pm= pressure at coupling head of service line
TR = sum of braking forces at periphery of all wheels of trailer
or semi-trailer
PR = total normal static reaction of road surface on wheels of
trailer or semi-trailer
PRmax= value of PR at ►M3maximum mass ◄of semi-trailer
ER= distance between king-pin and centre of axle or axles of
semi-trailer
hR= height above ground of centre of gravity of semi-trailer
specified by the manufacturer and agreed by the Technical
Servicesconducting the approval tes t1971L0320 — EN — 03.01.1986 — 005.001 — 26
(1) Adhesion curves used by each axle means curves showing the adhesion used by axle i
plotted against the vehicle braking rate under the specified load conditions.
(2) For semi-trailers, z is the braking force divided by the static ►M3mass◄on the
semi-trailer axle(s).▼M4
▼M2
▼M4
▼M2
▼M4
▼M2
3. REQUIREMENTS FOR MOTOR VEHICLES
3.1.Twoaxlevehicles.
3.1.1.(1) For all categoriesof vehiclesfor k valuesbetween 0,2 and 0,8:
z/C210;1þ0;85 k /C00;2 ðÞ
For all states of load of the vehicle, the adhesion utilization curve of
the front axle shall be situated above that for the rear axle:
— for all braking ratesof between 0,15 and 0,8 in the cas e of vehicles
of category M1.
However, for vehiclesof thiscategory over the range of z values
between 0,3 and 0,45, an inversion of the adhesion utilization
curvesispermitted provided that the adhes ion utilization curve of
the rear axle doesnot exceed by more than 0,05 the line defined by
the formula k = z (line of ideal adhesion utilization — see diagram
1 A),
— for all braking ratesof between 0,15 and 0,5 in the cas e of vehicles
of category N1(2).
This condition is also considered satisfied if, for braking rates
between 0,15 and 0,30, the adhesion utilization curves for each
axle are situated between two parallels to the line of ideal adhesion
utilization given by the equationsk = z + 0,08 and k = z − 0,08 as
shown in diagram 1 C, where the adhesion utilization curve for the
rear axle may cross the line k = z − 0,08 and, for braking rates
between 0,3 and 0,5, complieswith the relation z ≥k − 0,08,
and between 0,5 and 0,61 with the relation z ≥0,5 k + 0,21,
— for all braking ratesof between 0,15 and 0,30, in the cas e of other
categories.
This condition is also considered satisfied if, for braking rates
between 0,15 and 0,30, the adhesion utilization curves for each
axle are situated between two parallels to the line of ideal adhesion
utilization given by the equationsk = z + 0,08 and k = z − 0,08, as
shown in diagram 1 B, and the adhesion utilization curve for the
rear axle, for braking ratesz ≥0,3 complieswith the relation
z≥0,3 + 0,74 (k − 0,38).
3.1.2. In the case of a vehicle authorized to draw trailers of category O3or
O4fitted with compressed air brakes, when tested with the energy
source stopped, the supply line blocked off and a reservoir of 0,5-litre
capacity connected to the control line, the pressure at full application
of the braking control must be between 6,5 and 8 bar at the coupling
head of the supply line and between 6 and 7,5 bar at the coupling head
of the control line, irrespective of the load condition of the vehicle.
3.1.3. In order to verifiy the requirement of item 3.1.1, the manufacturer
shall provide the adhesion utilization curves for the front and rear
axlescalculated by the formulae:
f1¼T1
N1¼T1
P1þzh
EP;
f2¼T2
N2¼T2
P2/C0zh
EP:1971L0320 — EN — 03.01.1986 — 005.001 — 27
(1) The provisions of item 3.1.1 do not affect the requirements of Annex II relating to the
braking efficiency. However, if, when verifying the provisions of item 3.1.1 braking
efficiencies are obtained which are higher than those prescribed in Annex II, the provi-
sions relating to the adhesion utilization curve shall be applied within the areas ofdiagramsIA and IB defined by the s traight linesk = 0·8 and z = 0·8.
(
2) Vehiclesof category N1with a laden/unladen rear axle loading ratio not exceeding 1,5
or having a maximum mass of less than 2 tonnes will have comply with the require-
mentsfor category M1vehiclesof thisitem from 1 October 1990.▼M4
▼M4
The graphs shall be plotted for both the following load conditions:
— unladen, in running order with the driver on board.
In the case of a vehicle presented as a bare chassis-cab, a supple-
mentary load may be added to simulate the mass of the body, not
exceeding the minimum mass declared by the manufacturer in
Annex IX,
— laden.
Where provision is made for several possibilities of load distribu-
tion, the one whereby the front axle is the most heavily laden shall
be the one to be taken into consideration.
3.1.4. Vehicles other than tractive units for semi-trailers.
3.1.4.1. In the case of a vehicle fitted with compressed-air brakes, whether it is
a trailer or a motor vehicle authorized to draw a trailer, the permissible
relationship between the braking rateTR
PRorTM
PMand the pressure pm
shall be within the areas shown in diagram 2.
3.1.5. Tractive units for semi-trailers.
3.1.5.1. Tractive unitswith unladen s emi-trailer
An unladen articulated combination iscons idered to be a tractive unit
in running order with the driver on board, coupled to an unladen semi-
trailer. The dynamic load of the semi-trailer on the tractive unit shall
be represented by a static mass applied at the coupling king-pin equal
to 15 % of the maximum mass on the coupling. The braking forces
must continue to be regulated between the state of the tractive unit
with semi-trailer (unladen) and that of the solo tractive unit; the
braking forces relating to the solo tractive unit shall be verified.
3.1.5.2. Tractive unitswith laden s emi-trailer
A laden articulated combination iscons idered to be a tractive unit in
running order with the driver on board coupled to a laden semi-trailer.
The dynamic load of the semi-trailer on the tractive unit shall be
represented by a static ►M3mass◄Psapplied at the coupling
king-pin equal to:
Ps¼Pso1þ0/C145 z ðÞ
where Psorepresents the difference between the maximum laden
►M3mass◄of the tractive unit and itsunladen ►M3mass◄.
For h the following value shall be taken: h ¼hoPoþhsPs
P
where:
hoisthe height of the centre of gravity of the tractive unit
hsis the height of the coupling on which the semi-trailer rests
Poisthe unladen ►M3mass◄of the solo tractive unit
P=Po+Ps=P1+P2.
3.1.5.3. In the case of a vehicle fitted with a compressed air braking system,
the permissible relationship between the braking rate TM/PM and the
pressure pmshall be within the areas shown in diagram 3.
3.2.Vehicleswithmorethantwoaxles
The requirementsof item 3.1 s hall apply to vehicleswith more than
two axles. The requirements of item 3.1.1 with respect to wheel lock
sequence shall be considered to be met, if, in the case of braking rates
of between 0·15 and 0·30, the adhesion used by at least one of the
front axles is greater than that used by at least one of the rear axles.1971L0320 — EN — 03.01.1986 — 005.001 — 28
▼M2
▼M4
▼M2
▼M4
▼M2
▼M4
4. REQUIREMENT FOR SEMI-TRAILERS
4.1.Forsemi-trailers fittedwithcompressed-airbrakingsystems
The permissible relationship between the braking rateTR
PRand the pres-
sure pmshall lie within two areas derived from diagrams 4 A and 4 B
for the laden and unladen states of load. This requirement shall be met
for all permissible load conditions of the semi-trailer axles.
4.2. If the requirements of item 4.1 cannot be satisfied in conjunction with
the requirementsof item 2.2.1.2.1 of Annex II for s emi-trailerswith a
Kcfactor less than 0,8 then the semi-trailer must meet the minimum
braking performance specified in item 2.2.1.2.1 of Annex II and be
fitted with an anti-lock device complying with Annex X, except the
compatibility requirement in item 1 of that Annex.
5. REQUIREMENTS FOR FULL AND CENTRE-AXLE TRAILERS
5.1.Forfulltrailers fittedwithcompressed-airbrakingsystems
5.1.1. The requirements set out in item 3.1 shall apply to twin-axle trailers
(except where the axle spread is less than 2 metres).
5.1.2. Full trailers with more than two axles shall be subject to the require-
mentscontained in item 3.2.
5.2.Forcentre-axletrailersfittedwithcompressed-airbrakingsystems
5.2.1. The permissible relationship between the braking rateTR
PRand the pres-
sure pmshall lie within two areas derived from diagram 2, by
multiplying the vertical scale by 0,95, for the laden and unladen states
of load.
5.2.2. If the requirements of item 2.2.1.2.1 of Annex II cannot be satisfied
due to lack of adhesion, then the centre-axle trailer must be fitted
with an anti-lock device complying with Annex X.
6. CONDITIONS TO BE FULFILLED IN THE CASE OF FAILURE OF
THE BRAKING DISTRIBUTION SYSTEM
When the requirementsof thisAppendix are met by meansof a s pecial
device (e.g., controlled mechanically by the suspension of the vehicle),
it shall be possible in the event of failure of this device or its control
to stop the vehicle under the conditions prescribed for secondary
braking in the case of motor vehicles; in the case of trailers and
semi-trailers in the event of failure of the control a braking rate of at
least 30 % of the service brake performance prescribed for the vehicle
in question shall be attained.
7. MARKINGS
7.1. Vehicles, other than those of category M1, which meet the require-
mentsof thisAppendix by meansof a device mechanically controlled
by the suspension of the vehicle, shall be marked to show the useful
travel of the device between the positions corresponding to vehicle
unladen and laden states respectively.
7.2. When the requirementsof thisAppendix are met by meansof a device
actuated by compressed air, the vehicle shall be marked to show the
pressure values at the outlet side of the device during full braking of
the vehicle under both unladen and laden conditions.
7.3. The markingsreferred to under items7.1 and 7.2 above s hall be
affixed in a visible position in indelible form.
8. PRESSURE TEST CONNECTIONS
8.1. Braking systems incorporating the devices referred to in item 7.2 shall
be fitted with pressure test connections in the pressure line upstream
and downstream of the device, at the closest readily accessible posi-
tions. The downstream connection shall not be required, if the
pressure at that point can be checked at the connection required by
item 4.1 of Annex III.1971L0320 — EN — 03.01.1986 — 005.001 — 29
▼C2
▼M2
▼M4
▼M4
8.2. The pressure test connections shall comply with clause 3 of ISO Stan-
dard 3583/1982.1971L0320 — EN — 03.01.1986 — 005.001 — 30
▼M2
DIAGRAM 1 A
VEHICLES OF CATEGORY M1, ANDCERTAIN VEHICLES OF CATEGORY N1FROM 1
OCTOBER1990
(see item 3.1.1)
1971L0320 — EN — 03.01.1986 — 005.001 — 31
▼M4
▼M2
▼M2
DIAGRAM 1 B
VEHICLESOTHERTHANVEHICLESOFCATEGORYM1ANDN1
(see item 3.1.1)
Note:
The lower limit of the corridor isnot applicable for the adhes ion utilization of the rear axle.1971L0320 — EN — 03.01.1986 — 005.001 — 32
▼M4
▼M2
▼M4
▼M4
DIAGRAM 1 C
VEHICLESOFCATEGORYN1(WITHCERTAINEXCEPTIONSFROM1OCTOBER1990)
(see item 3.1.1)
Note:
The lower limit of the corridor isnot applicable for the adhes ion utilization of the rear axle.1971L0320 — EN — 03.01.1986 — 005.001 — 33
▼M2
DIAGRAM 2
DRAWINGVEHICLESANDTRAILERS
(see item 3.1.4.1)
Note:►
M4(1)◄It isunders tood that between the valuesTM
PM¼0 andTM
PM¼0/C11o rTR
PR¼0 and
TR
PR¼0/C11 it is not necessary that there should be proportionality between the braking rateTM
PM
orTR
PRand the control pressure as measured at the coupling head.
(2) The relationships required by the diagram shall apply progressively for intermediate states of
loading between the laden and the unladen states and shall be achieved by automatic means.1971L0320 — EN — 03.01.1986 — 005.001 — 34
▼M4
▼M2
DIAGRAM 3
TRACTIVEUNITSFORSEMI-TRAILERS
(see item 3.1.5)
Note:
(1) Between the valuesTM
PM¼0 andTM
PM¼0/C11;it is not necessary that there should be proportion-
ality between the braking rateTM
PMand the service line pressure as measured at the coupling head.
(2) The relationships required by the diagram shall apply progressively for intermediate states of
loading between the laden and the unladen states and shall be achieved by automatic means.1971L0320 — EN — 03.01.1986 — 005.001 — 35
▼M2
DIAGRAM 4 A
SEMI-TRAILERS
(see item 4)
The relationship between the braking rateTR
PRand control line pressure for the laden and unladen
condition isdetermined asfollows :
The factorsKc(laden), Kv(unladen) are obtained by reference to diagram 4 B.
Construct the laden and unladen bands by multiplying the upper and lower boundaries of the band in
diagram 4 A shown below by the two factors obtained, Kcand Kvrespectively.1971L0320 — EN — 03.01.1986 — 005.001 — 36
▼M2
DIAGRAM 4 B
(see item 4)
1971L0320 — EN — 03.01.1986 — 005.001 — 37
▼M2
Explanatorynoteontheuseofdiagram4B
1. Formula from which Diagram 4 B isderived is :
K¼1/C17/C00/C17P R
PRmax/C20/C21
1/C135/C00/C196
ER1/C10þhR/C01/C12 ðÞP
PR/C18/C19 /C20/C21
/C01/C10/C0PR
PRmax/C20/C21hR/C01/C10
2/C15/C20/C21
2. Description of the method of use by means of a worked example.
2.1. The dashed lines shown on Diagram 4B refer to the determination of the factors Kcand Kvfor
the following vehicle where:
Laden Unladen
P 24 t 4·2 t
PR 15 t 3 tPR
max15 t 15 t
hR1·8 m 1·4 m
ER6·0 m 6·0 m
In the following items the figures in parenthesis relate only to the vehicle being used for the
purpose of illustrating the method of use of Diagram 4B.
2.2. Calculate the ratios
(a)P
PR/C20/C21
laden (= 1·6)
(b)P
PR/C20/C21
unladen (= 1·4)
(c)PR
PRmax/C20/C21
unladen (= 0·2)
2.3. Determination of the laden factor, Kc
(a) Start at appropriate hR(hR= 1·8 m)
(b) Move horizontally to the appropriate P/PR line (P/PR = 1·6)
(c) Move vertically to appropriate ERline (ER= 6·0) m
(d) Move horizontally to Kcscale, Kcisthe laden factor required (Kc= 1·04).
2.4. Determination of the unladen factor, Kv.
2.4.1. Determination of the factor K2
(a) Start at appropriate hR(hR= 1·4) m
(b) Move horizontally to appropriate PR/PRmaxline in group of curvesneares t to vertical axis
(PR/PRmax= 0·2)
(c) Move vertically to horizontal axisand read off the value of K2(K2= 0·13 m).
2.4.2. Determination of factor K1
(a) Start at appropriate hR(hR= 1·4 m)
(b) Move horizontally to the appropriate P/PR line (P/PR = 1·4)
(c) Move vertically to the appropriate ERline (ER= 6·0 m)
(d) Move horizontally to the appropriate PR/PRmaxline in group of curvesfurthes t from the
vertical axis.
(PR/PRmax= 0·2)
(e) Move vertically to horizontal axisand read off the value of K1(K1= 1·79).
2.4.3. Determination of factor Kv
The unladen factor Kvis obtained from the following expression: K v¼K1/C0K2Kv¼1/C166 ðÞ :1971L0320 — EN — 03.01.1986 — 005.001 — 38
▼B
ANNEX III
METHODOF MEASURING THE REACTION TIME FOR VEHICLES
FITTEDWITHCOMPRESSEDAIRBRAKINGDEVICES
1. GENERAL REQUIREMENTS
1.1. The reaction time for the braking device shall be determined with the
vehicle stationary, the pressure being measured at the opening of the
least favourable brake cylinder. In the case of vehicles fitted with
combined compressed-air/hydraulic braking systems, the pressure may
be measured at the opening of the least favourable pneumatic unit.
1.2. During the tests, the stroke of the brake cylinders of the individual axles
must be that corresponding to the most closely adjusted brakes.
1.3. The timesdetermined in implementing the provis ionsof thisAnnex
shall be rounded to the nearest 10th of a second. If the figure repre-
senting the 100ths is five or more, the reaction time shall be rounded
up to the next higher 10th.
2. MOTOR VEHICLES
2.1. At the start of each test, the pressure in the reservoirs must be equal to
the minimum pressure at which the governor starts feeding the installa-
tion again. In installations not fitted with a governor (e.g. pressure
limited compressor) the pressure in the reservoir at the start of each
test must be equal to 90% of the pressure stated by the manufacturer,
as defined in item 1.2.2.1 of Annex IV, to be used for tests prescribed
in thisAnnex.
2.2. Reaction timesin termsof actuation time (tf) s hall be obtained by a
series of actuations to the fullest extent, starting from the shortest
possible up to a time of about 0·4 seconds. The values measured must
be given on a diagram.
2.3. Reaction times corresponding to an actuation time of 0·2 seconds shall
be determinant for the test. This reaction time can be obtained from the
diagram by interpolation.
2.4. In the case of the actuation time of 0·2 seconds, the time elapsing
between the beginning of actuation of the control pedal and the moment
when the pressure in the brake cylinder reaches 75% of its asymptotic
value must not exceed 0·6 seconds.
2.5. In the case of motor vehicles having a brake coupling for trailers, in
addition to the requirementsof item 1.1 the reaction time mus t be
measured at the extremity of a pipe 2·5 m long with an internal diameter
of 13 mm which shall be joined to the coupling head of the control lineof the service brake. During this test a volume of 385 ± 5 cm
3(which is
deemed to be equivalent to the volume of a pipe 2·5 m long with an
internal diameter of 13 mm and under a pressure of 6·5 bar) shall be
connected to the coupling head of the supply line.
Tractive units for semi-trailers must be equipped with flexible pipes for
making the connection to semi-trailers. The coupling heads will there-
fore be at the extremity of those flexible pipes. The length and internal
diameter of the pipess hall be entered at item 14.6 of the document
corresponding to the model described in Annex IX.
2.6. The time which elapses between the start of the activation of the control
pedal and the moment when the pressure measured at the coupling head
of the control pipe reaches x% of its asymptotic value must not exceed
the valueslis ted in the table below:1971L0320 — EN — 03.01.1986 — 005.001 — 39
▼M3
▼B
▼M4
▼B
▼M3
▼B
▼M3
▼B
▼B
x (%) t (seconds)
10 0·2
75 0·4
3. TRAILERS (including semi-trailers)
3.1. The reaction times for trailers shall be measured without a drawing
vehicle. To simulate the drawing vehicle it is necessary to provide a
simulator to which the coupling heads of the control pipe and of the
feed pipe of the trailer are to be connected.
3.2. The pressure in the feed pipe must be 6·5 bars. ►M3 ◄
3.3. The simulator must have the following features:
3.3.1. It must have a reservoir with a capacity of 30 litres which shall
be charged to a pressure of 6·5 bar before each test and which
must not be recharged during each test. At the outlet of the
braking control device the simulator must incorporate an orifice
with a diameter of from 4·0 to 4·3 mm inclusive. The volume of
the pipe measured from the orifice up to and including the
coupling head shall be 385 ± 5 cm3(which isdeemed to be
equivalent to the volume of a pipe 2·5 m long with an internal
diameter of 13 mm and under a pressure of 6·5 bar). The control
line pressures referred to in item 3.3.3 shall be measured immedi-
ately downstream of the orifice.
3.3.2. The braking control device must be so designed that its perfor-
mance in use is not affected by the tester.
3.3.3. The simulator must be set, e.g. through the choice of orifice in
accordance with item 3.3.1, in such a way that, if a reservoir of
385 ± 5 cm3is joined to it, the time taken for the pressure to
increase from 0·65 to 4·9 bar (10 and 75% respectively of the
nominal pressure of 6·5 bar), shall be 0·2 ± 0·01 second. If a
reservoir of 1 155 ± 15 cm3is substituted for the abovementioned
reservoir, the time taken for the pressure to increase from 0·65 to
4·9 bar without further adjustment shall be 0·38 ± 0·02 second.
Between these two pressure values the pressure must increase in
an approximately linear way. These reservoirs shall be connected
to the coupling head without using flexible pipes and shall have
an internal diameter of not less than 10 mm.
3.3.4. The diagram in the Appendix to thisAnnex givesan example of
the correct configuration and use of the simulator.
3.4. The time elapsing between the moment when the pressure produced in
the control line by the simulator reaches 0·65 bar and the moment when
the pressure in the brake actuator of the trailer reaches 75% of its
asymptotic value must not exceed 0·4 second.
4. PRESSURE TEST CONNECTIONS
4.1. On each independant circuit of the braking system a pressure test
connection shall be fitted at the closest readily accessible position to
the brake cylinder which isthe leas t favourably placed asfar asreaction
time isconcerned.
4.2. The pressure test connections shall comply with clause 3 of ISO Stan-
dard 3583/1982.1971L0320 — EN — 03.01.1986 — 005.001 — 40
▼M3
▼M4
▼M3
APPENDIX
EXAMPLEOFASIMULATOR(SEEANNEXIII,ITEM3)
1. Setting the simulator
2. Testing the trailer
A = supply connection with shut-off valve
C1 = pressure switch in the simulator, set at 0·65 bar and at 4·9 barC2 = pressure switch to be connected to the brake actuator of the trailer, to operate at 75% of
the asymptotic pressure in the brake actuator CF
CF = brake actuatorL = line from orifice O up to and including itscoupling head TC, having an inner volume of
385 ± 5 cm
3under a pressure of 6·5 bar
M = pressure gaugeO = orifice with a diameter of not less than 4 mm and not more than 4·3 mmPP = pressure test connectionR1 = 30 litre air reservoir with drain valveR2 = calibrating reservoir, including its coupling head TC, to be 385 ± 5 cm
3
R3 = calibrating reservoir, including its coupling head TC, to be 1 155 ± 15 cm3
RA = shut-off valve1971L0320 — EN — 03.01.1986 — 005.001 — 41
▼M3
TA = coupling head, supply line
TC = coupling head, control lineV = braking control deviceVRU = emergency relay valve1971L0320 — EN — 03.01.1986 — 005.001 — 42
▼B
ANNEX IV
ENERGYRESERVOIRSANDSOURCESOFENERGY
A.COMPRESSED-AIR BRAKING SYSTEMS
1. CAPACITY OF RESERVOIRS
1.1.General requirements
1.1.1. Vehicleson which the operation of the braking devicesdepends
on the use of compressed air must be fitted with reservoirs of a
capacity meeting the requirementsof items1.2 and 1.3 below.
1.1.2. Nevertheless, the capacity of reservoirs shall not be laid down
where the braking system is such that in the absence of any
energy reserve it is possible to achieve a braking performance at
least equal to that prescribed for the secondary braking.
1.1.3. When verifying compliance with the requirementsof items1.2
and 1.3 the brakes must be adjusted as closely as possible.
1.2.Motorvehicles
1.2.1. The air brake reservoirs of motor vehicles shall be so designed
that after eight full-stroke actuations of the service brake control
the pressure remaining in the air brake reservoir shall be not less
than the pressure required to obtain the specified secondary
braking performance.
1.2.2. During the test, the following requirements are to be satisfied:
1.2.2.1. The initial pressure in the reservoirs must be that indi-
cated by the manufacturer. This pressure must be such
as to enable the prescribed performance for the service
braking to be achieved;
1.2.2.2. The reservoir or reservoirs must not be replenished; in
addition, the reservoir or reservoirs of auxiliary equip-
ment must be isolated;
1.2.2.3. In the case of motor vehicles to which the coupling of a
trailer or semi-trailer is authorised, the feed line must be
blocked off and a reservoir of 0·5 litre capacity must be
connected to the control line. The pressure in this reser-
voir must be exhausted before each actuation of the
brakes. After the test referred to in item 1.2.1 the pres-
sure in the control line must not be less than one half of
the pressure obtained at the first brake application.
1.3.Trailers (includingsemi-trailers)
1.3.1. Reservoirs fitted to trailers must be such that after eight full-
stroke actuations of the drawing vehicle's service braking device,
the pressure supplied to the operating parts using it is not less
than one half of the pressure obtained at the first brake applica-
tion.
1.3.2. During the test, the following requirements are to be satisfied:
1.3.2.1. The pressure in the reservoirs at the beginning of the test
must be equal to the maximum specified by the manufac-
turers;
1.3.2.2. The feed line must be blocked off; in addition, the
auxiliary equipment reservoirs must be isolated;
1.3.2.3. The reservoir shall not be replenished during the test;
1.3.2.4. For each application of the brakes, the pressure in the
control pipe must correspond to the maximum specified
by the manufacturer.1971L0320 — EN — 03.01.1986 — 005.001 — 43
▼M4
▼B
▼M3
▼B
▼M4
▼B
▼B
2. CAPACITY OF ENERGY SOURCES
2.1.General provisions
Compressors must satisfy the requirements laid down in the following
items:
2.2.Definitions
2.2.1. p1is the pressure corresponding to 65% of the pressure p2defined
in item 2.2.2
2.2.2. p2isthe value s pecified by the manufacturer and referred to in
item 1.2.2.1
2.2.3. T1is the time required for the relative pressure to rise from O to
p1;T2is the time required for the relative pressure to rise from O
to p2.
2.3.Conditionsofmeasurement
2.3.1. In all cases the rpm speed of the compressor shall be that
obtained when the engine is running at the speed corresponding
to itsmaximum power or at the s peed allowed by the control
valve.
2.3.2. The auxiliary equipment reservoirs shall be isolated during the
tests for determining the periods T1and T2.
2.3.3. On motor vehicles constructed to draw trailers, the trailer shall be
represented by a reservoir whose maximum relative pressure p
(expressed in bars) is that which can be supplied through the
feed circuit of the drawing vehicle and whose volume V
(expressed in litres) is given by the formula p · V = 20 R (R
being the permissible maximum load, expressed in metric tons,
on the axlesof the trailer or s emi-trailer).
2.4.Interpretationofresults
2.4.1. The time T1for the least efficient reservoir must not exceed:
— three minutesin the cas e of vehiclesto which the coupling of
a trailer or semi-trailer is not authorised;
— six minutes in the case of vehicles to which the coupling of a
trailer or semi-trailer is authorised.
2.4.2. The time T2for the least efficient reservoir must not exceed:
— six minutes in the case of vehicles to which the coupling of a
trailer or semi-trailer is not authorised;
— nine minutesin the cas e of vehiclesto which the coupling of
a trailer or semi-trailer is authorised.
2.5.Additionaltest
2.5.1. When the vehicle isequipped with an auxiliary equipment res er-
voir or reservoirs with a total capacity exceeding 20% of the total
capacity of the brake reservoirs, an additional test must be carried
out during the course of which there must be no interference with
the functioning of the valvescontrolling the filling of the
auxiliary equipment reservoir(s). A check must be made during
the course of this test that the period T3required to bring about
a rise in the pressure in the brake reservoirs from O to p2isles s
than:
— eight minutesin the cas e of vehiclesto which the coupling of
a trailer or semi-trailer is not authorised;
— eleven minutesin the cas e of vehiclesto which the coupling
of a trailer or semi-trailer is authorised.
2.6.Drawingvehicles
2.6.1. Vehiclesto which the coupling of a category O vehicle isauthor-
ized shall also comply with the above requirements for vehicles
not so authorized. In that case, the tests in items 2.4.1, 2.4.2
(and 2.5.1) will be conducted without the reservoir mentioned in
item 2.3.3 of thisAnnex.1971L0320 — EN — 03.01.1986 — 005.001 — 44
▼M4
▼M3
3. PRESSURE TEST CONNECTIONS
3.1. A pressure test connection must be fitted at the closest readily accessible
position to the least favourably placed reservoir within the meaning of
item 2.4 of thisAnnex.
3.2. The pressure test connections must comply with clause 3 of ISO Stan-
dard 3583/1982.
B.VACUUM BRAKING SYSTEMS
1. CAPACITY OF RESERVOIRS
1.1.General
1.1.1. Vehicleson which operation of the braking device requiresthe
use of a vacuum shall be equipped with reservoirs of a capacity
meeting the requirementsof items1.2 and 1.3 below.
1.1.2. However, the reservoirs shall not be required to be of a
prescribed capacity if the braking system is such that in the
absence of any energy reserve it is possible to achieve a braking
performance at least equal to that prescribed for the secondary
braking system.
1.1.3. In verifying compliance with the requirementsof items1.2 and
1.3 below, the brakes shall be adjusted as closely as possible.
1.2.Motorvehicles
1.2.1. The reservoirs of motor vehicles shall be such that it is still
possible to achieve the performance prescribed for the secondary
brake:
1.2.1.1. after eight full-stroke actuations of the service-brake
control where the energy source is a vacuum pump; and
1.2.1.2. after four full-stroke actuations of the service-brake
control where the energy source is the engine.
1.2.2. Testing shall be performed in conformity with the following
requirements:
1.2.2.1. the initial energy level in the reservoir(s) shall be that
specified by the manufacturer. It shall be such as to
enable the prescribed service-braking performance to be
achieved and shall correspond to a vacuum not
exceeding 90 % of the maximum vacuum furnished by
the energy source(1);
1.2.2.2. the reservoir(s) shall not be fed. During the test the
auxiliary-service reservoir(s) shall be isolated;
1.2.2.3. on a motor vehicle to which the coupling of a trailer is
authorized, the supply line shall be stopped and a reser-
voir of 0,5-litre capacity shall be connected to the control
line. After the test referred to in item 1.2.1, the vacuum
level provided at the control line shall not have fallen
below a level equivalent to one-half of the figure
obtained at the first brake application.
1.3.Trailers (category O1andO2only)
1.3.1. The reservoir(s) with which trailers are equipped shall be such
that the vacuum level provided at the user points shall not have
fallen below a level equivalent to one-half of the value obtained
at the first brake application after a test comprising four full-
stroke actuations of the trailer's service brake.
1.3.2. Testing shall be performed in conformity with the following
requirements:1971L0320 — EN — 03.01.1986 — 005.001 — 45
(1) The initial energy level shall be stated in the approval document.▼M4
▼M4
1.3.2.1. The initial energy level in the reservoir(s) shall be that
specified by the manufacturer. It shall be such as to
enable the prescribed service braking performance to be
achieved(1).
1.3.2.2. The reservoir(s) shall not be fed. During the test the
auxiliary service reservoir(s) shall be isolated.
2. CAPACITY OF ENERGY SOURCES
2.1.General
2.1.1. Starting from the ambient atmospheric pressure, the energy
source shall be capable of achieving in the reservoir(s) in three
minutes, the initial level specified in item 1.2.2.1. In the case of
a motor vehicle to which the coupling of a trailer isauthorized
the time taken to achieve that level in the conditionss pecified in
item 2.2 below shall not exceed six minutes.
2.2.Conditionsofmeasurement
2.2.1. The speed of the vacuum source shall be:
2.2.1.1. where the vacuum source is the vehicle engine, the
engine speed obtained with the vehicle stationary, the
neutral gear engaged and the engine idling;
2.2.1.2. where the vacuum source is a pump, the speed obtained
with the engine running at 65 % of the speed corre-
sponding to its maximum power output; and
2.2.1.3. where the vacuum source is a pump and the engine is
equipped with a governor, the speed obtained with the
engine running at 65 % of the maximum speed allowed
by the governor.
2.2.2. Where it isintended to couple to the motor vehicle a trailer
whose service braking system is vacuum-operated, the trailer
shall be represented by an energy storage device having a capa-
city V in litresdetermined by the formula V = 15 R, where R is
the maximum permissible mass, in tonnes, on the axles of the
trailer.
C.HYDRAULIC BRAKING SYSTEMS WITH STORED ENERGY
1. CAPACITY OF STORAGE DEVICES (ENERGY ACCUMULATORS)
1.1.General
1.1.1. Vehicles on which the braking device requires the use of stored
energy provided by hydraulic fluid under pressure shall be
equipped with energy storage devices (energy accumulators) of a
capacity meeting the requirementsof item 1.2 below.
1.1.2. However, the energy storage devices shall not be required to be
of a prescribed capacity if the braking system is such that in the
absence of any energy reserve it is possible with the service brake
control to achieve a braking performance at least equal to that
prescribed for the secondary braking system.
1.1.3. In verifying compliance with the requirementsof items1.2.1,
1.2.2 and 2.1 below, the brakes shall be adjusted as closely as
possible and, for item 1.2.1, the rate of full-stroke actuations
must be such as to provide an interval of at least one minute
between each actuation.
1.2.Motorvehicles
1.2.1. Motor vehicles equipped with a hydraulic braking system with
stored energy shall meet the following requirements:
1.2.1.1. after eight full-stroke acutations of the service braking
control, it shall still be possible to achieve, on the ninth
application, the performance prescribed for the secondary
braking system.1971L0320 — EN — 03.01.1986 — 005.001 — 46
(1) The initial energy level shall be stated in the approval document.
▼M4
1.2.1.2. Testing shall be performed in conformity with the
following requirements:
1.2.1.2.1. testing shall commence at a pressure that may
be specified by the manufacturer but is not
higher than the cut-in pressure;
1.2.1.2.2. the accumulator(s) shall not be fed; in addi-
tion, the auxiliary equipment and its
accumulators, if any, shall be isolated.
1.2.2. Motor vehicles equipped with a hydraulic braking system with
stored energy which cannot meet the requirements of item
2.2.1.5.1 of Annex I shall be deemed to satisfy that item if the
following requirementsare met:
1.2.2.1. After any single transmission failure it shall still be
possible after eight full-stroke actuations of the service
braking control, to achieve, at the ninth application, at
least the performance prescribed for the secondary
braking system or, where secondary performance
requiring the use of stored energy is achieved by a sepa-
rate control, it shall still be possible after eight full-
stroke actuations to achieve, at the ninth application, the
residual performance prescribed in item 2.2.1.4 of Annex
I.
1.2.2.2. Testing shall be performed in conformity with the
following requirements:
1.2.2.2.1. with the energy source stationary or operating
at a speed corresponding to the engine idling
speed, any transmission failure may be
induced. Before inducing such a failure the
energy storage device(s) shall be at a pressure
that may be specified by the manufacturer but
not exceeding the cut-in pressure;
1.2.2.2.2. the auxiliary equipment and itsaccumulators ,
if any, shall be isolated.
2. CAPACITY OF HYDRAULIC FLUID ENERGY SOURCES
2.1.The energy sources shall meet the requirements set out in the
followingparagraphs:
2.1.1.Definitions
2.1.1.1. ‘p1’ represents the maximum system operational pressure
(cut-out pressure) in the accumulator(s) specified by the
manufacturer.
2.1.1.2. ‘p2’ represents the pressure after four full-stroke actua-
tions with the service brake control, starting at p1,
without having fed the accumulator(s).
2.1.1.3 ‘t’ represents the time required for the pressure to rise
from p2to p1in the accumulator(s) without application
of the brake control.
2.1.2.Conditions of measurement
2.1.2.1. During the test to determine the time t, the feed rate of
the energy source shall be that obtained when the engine
is running at the speed corresponding to its maximum
power or at the speed allowed by the over-speed
governor.
2.1.2.2. During the test to determine the time t, accumulator(s)
for auxiliary equipment shall not be isolated other than
automatically.
2.1.3.Interpretation of results
2.1.3.1. In the case of all vehicles except those of categories M3,
N2and N3, the time t shall not exceed 20 seconds.
2.1.3.2. In the case of vehicles of categories M3,N2and N3, the
time t shall not exceed 30 seconds.1971L0320 — EN — 03.01.1986 — 005.001 — 47
▼M4
3. CHARACTERISTICS OF ALARM DEVICES
With the engine stationary and commencing at a pressure that may be speci-
fied by the manufacturer but does not exceed the cut-in pressure, the alarm
device shall not operate following two full-stroke actuations of the service
brake control.1971L0320 — EN — 03.01.1986 — 005.001 — 48
▼B
ANNEX V
SPRINGBRAKES
1. DEFINITIONS
1.1. ‘Spring brakes’ are braking devices for which the energy required for
braking is supplied by one or more springs acting as an energy accumu-
lator.
1.2. ‘Spring compression chamber’ means the chamber where the pressure
variation that induces the compression of the spring is actually
produced.
1.3. If the compression of the springs is obtained by means of a vacuum
device, ‘pressure’ shall mean negative pressure everywhere in this
Annex.
2. GENERAL REQUIREMENTS
2.1. A spring brake shall not be used as a service brake. However, in the
event of a failure in a part of the transmission of the service brake, a
spring brake may be used to achieve the residual performance prescribed
in item 2.2.1.4 of Annex I, provided that the driver can graduate this
action. In the case of motor vehicles, with the exception of drawing
vehicles for semi-trailers meeting the requirements specified in item
2.2.1.4.3 of Annex I, the spring brake shall not be the sole source of
residual braking.
Vacuum spring brakes shall not be used for trailers.
2.2. A small variation in any of the pressure limits which may occur in the
spring compression chamber feed circuit must not cause a significant
variation in the braking force.
2.3. The feed circuit to the spring compression chamber must either include
an own energy reserve or must be fed from at least two independent
energy reserves. The trailer supply line may be branched from this feed
line under the condition that a pressure drop in the trailer supply line
must not be able to apply the spring brake actuators. Auxiliary equip-
ment may only draw itsenergy from the feed line for the s pring brake
actuatorsunder the condition that itsoperation, even in the event of
damage to the energy source, cannot cause the energy reserve for the
spring brake actuators to fall below a level from which one release of
the spring brake actuators is possible.
Thisitem doesnot apply to trailers .
2.4. In motor vehicles, the system must be so designed that it is possible to
apply and release the brakes at least three times if the initial pressure in
the spring compression chamber is equal to the maximum design pres-
sure. In the case of trailers, it must be possible to release the brakes at
least three times after the trailer has been uncoupled, the pressure in the
supply line being 6·5 bar before the uncoupling. These conditions must
be satisfied when the brakes are adjusted as closely as possible. In addi-
tion, it must be possible to apply and release the parking brake as
specified in Annex I, item 2.2.2.10, when the trailer is coupled to the
towing vehicle.
2.5. In the case of motor vehicles, the pressure in the spring compression
chamber beyond which the springs begin to actuate the brakes, the latter
being adjusted as closely as possible, must not be greater than 80 % of
the minimum level of the normal available pressure. In the case of trai-
lers, the pressure in the spring compression chamber beyond which the
springs begin to actuate the brakes must not be greater than that
obtained after four full-stroke actuations of the service brake in accor-
dance with Annex IV, item 1.3. The initial pressure is fixed at 6,5 bar.
2.6. When the pressure in the line feeding energy to the spring compression
chamber — excluding lines of an auxiliary release device using a fluid
under pressure — falls to the level at which the brake parts begin to
move, an optical or audible warning device must be actuated. Provided
thisrequirement ismet, the warning device may be that s pecified in
item 2.2.1.13 of Annex I. This provision does not apply to trailers.1971L0320 — EN — 03.01.1986 — 005.001 — 49
▼M4
▼B
▼M4
▼M3
▼M4
▼B
2.7. On motor vehicles fitted with spring brakes and authorised to draw trai-
lers with continuous or semi-continuous brakes, automatic application of
the spring brakes must cause the trailer brakes to be applied.
3. RELEASE SYSTEM
3.1. A spring braking system must be so designed that, in the event of a
failure in that system, it is still possible to release the brakes. This may
be achieved by the use of an auxiliary release device (pneumatic,
mechanical, etc.). Auxiliary release devices using an energy reserve for
releasing, must draw their energy from an energy reserve which is inde-
pendent from the energy reserve normally used for the spring braking
system.
The pneumatic or hydraulic fluid in such an auxiliary release device
may act on the same piston surface in the spring compression chamber,
which is used for the normal spring braking system, under the condition
that the auxiliary release device uses a separate line. The junction of this
line with the normal line connecting the control device with the spring
brake actuators, shall be at each spring brake actuator immediately
before the port to the spring compression chamber, if not integrated in
the body of the actuator. Thisjunction s hall include a device which
preventsan influence of one line on the other. The requirementsof
item 2.2.1.6 of Annex I also apply to this device.
3.2. If the operation of the auxiliary device referred to in item 3.1 requires
the use of a tool or spanner, the tool or spanner must be kept on the
vehicle.1971L0320 — EN — 03.01.1986 — 005.001 — 50
▼M4
▼B
▼B
ANNEX VI
PARKING BRAKING BY MECHANICAL LOCKING OF THE BRAKE
CYLINDERS
(lockactuators)
1. DEFINITION
‘Mechanical locking of the brake cylinders’ means a device for ensuring
parking braking by mechanical wedging of the brake piston rod.
Mechanical locking occurswhen the locking chamber isemptied of
compressed air; the mechanical locking device shall be designed in such a
way that it can be released when the locking chamber is again subjected to
pressure.
2. SPECIAL PROVISIONS
2.1. When the pressure in the locking chamber approaches the level corre-
sponding to mechanical locking, an optical or audible warning system
must be actuated. ►M3This provision shall not apply to trailers. In
the case of trailers the pressure corresponding to mechanical locking
must not exceed 4 bar. It must be possible to achieve parking brake
performance after any single failure of the trailer service braking
system. In addition, it must be possible to release the brakes at least
three times after the trailer has been uncoupled, the pressure in the
supply line being 6·5 bar before the uncoupling. These conditions must
be satisfied when the brakes are adjusted as closely as possible. It must
also be possible to apply and release the parking brake as specified in
Annex I, item 2.2.2.10, when the trailer iscoupled to the towing
vehicle. ◄
2.2. In the case of brake actuators fitted with a mechanical locking device,
the brake actuator must be capable of being actuated by either of two
energy reserves.
2.3. The locked brake cylinder may only be released if it is certain that the
brake can be operated again after such release.
2.4. In the event of a failure of the source of energy supplying the locking
chamber, an auxiliary unlocking device (mechanical or pneumatic, for
instance) using, for example, the air in one of the tyres of the vehicle,
must be provided.
2.5. The control must be such that, when actuated, it performs the following
operations in sequence: it applies the brakes so as to provide the degree
of efficiency required for parking braking, locksthe brakesin that pos i-
tion and then cancelsout the brake-application force.1971L0320 — EN — 03.01.1986 — 005.001 — 51
▼M3
▼B
ANNEX VII
CASESINWHICHTYPEIAND/ORII(ORIIA)TESTSDONOTHAVE
TO BE CARRIEDOUT ON A VEHICLE SUBMITTEDFOR TYPE
APPROVAL
1. Type I and/or II (or IIA) tests do not have to be carried out on a vehicle
submitted for type approval in the following cases:
1.1. where the vehicle in question is a motor vehicle, a trailer or a semi-
trailer which, in respect of tyres, braking energy absorbed by each axle
and method of fitting of tyresand brakes , isidentical, asfar asbraking
isconcerned, to a motor vehicle, a trailer, or a s emi-trailer which:
1.1.1. has passed a Type I and/or II (or II A) test;
1.1.2. hasbeen type approved, with regard to braking energy abs orbed,
for axle ►M3masses ◄greater than or equal to those of the
vehicle submitted for type approval.
1.2. where the vehicle in question is a motor vehicle, a trailer or a semi-
trailer of which the axle or axles, in respect of tyres, braking energy
absorbed by each axle and method of fitting of tyres and brakes, is or
are identical, asfar asbraking isconcerned, to an axle or axleswhich
has or have individually passed a Type I and/or II test for axle
►M3masses ◄greater than or equal to those of the vehicle submitted
for type approval, provided that the braking energy absorbed by each
axle doesnot exceed the energy abs orbed by that axle during the refer-
ence test or tests carried out separately on that axle.
1.3. where the vehicle submitted for type approval is fitted with a retarder,
other than an engine brake, identical to a retarder which hasalready
been tested under the following conditions:
1.3.1. in a test carried out on a gradient of at least 6% (Type II test) or
of at least 7% (Type II A test), this retarder has, on its own, stabi-
lised the speed of a vehicle with a ►M3maximum mass ◄at
the time of testing at least equal to the ►M3maximum mass ◄
of the vehicle submitted for type approval;
1.3.2. in the above test, a check must be made as to whether the speed
of rotation of the revolving partsof the retarder iss uch that,
when the vehicle submitted for type approval is travelling at a
speed of 30 km/h, the retarding torque is at least equal to the
retarding torque in the test mentioned in item 1.3.1.
1.4. The vehicle concerned isa trailer equipped with S-cam air operated
brakes(1) which satisfies the verification requirements of Appendix 1 to
this Annex relating to a report of a reference axle test as shown in
Appendix 2 to thisAnnex.
2. The term ‘identical’ asus ed in items1.1, 1.2 and 1.3 meansidentical as
regardsthe geometrical and mechanical characteris ticsof the vehicle parts
mentioned in those items, and also as regards the characteristics of the mate-
rialsfrom which thes e partsare made.
3. When advantage is taken of the above provisions, the type approval commu-
nication in respect of braking (Annex IX) must contain the following
particulars:
3.1. where item 1.1 isapplicable, the type of the approval number of the
vehicle on which the Type I and/or II (or II A) test serving as a refer-
ence test has been carried out (item 14.7.1 of Annex IX);
3.2. where item 1.2 isapplicable, the table in item 14.7.2 of the model item
of the communication in Annex IV must be completed;
3.3. where item 1.3 isapplicable, the table in item 14.7.3 of the model of the
communication in Annex IX must be completed;
3.4. where item 1.4 isapplicable, the table in item 14.7.4 of the model of the
communication in Annex IX must be completed.1971L0320 — EN — 03.01.1986 — 005.001 — 52
(1) Other brake designs may be approved upon presentation of equivalent information.▼M4
▼B
▼M4
▼B
▼M4
▼B
4. When a person applying for type approval in a Member State refers to a type
approval granted in another Member State, that person must produce the
documentsrelating to s uch approval.1971L0320 — EN — 03.01.1986 — 005.001 — 53
▼M4
Appendix 1
ALTERNATIVEPROCEDURESFORTYPEIANDTYPEIITESTSFOR
TRAILERBRAKES
1. GENERAL
1.1. In accordance with item 1.4 of thisAnnex, the Type I and II fade
tests may be waived at the time of type approval of the vehicle
provided that the braking system components comply with the
requirementsof thisAppendix and that the res ulting predicted
brake performance meetsthe pres criptionsof thisDirective for
the appropriate vehicle category.
1.2. Tests carried out in accordance with the methods detailed in this
Appendix shall be deemed to meet the above requirements.
2. SYMBOLS AND DEFINITIONS (The reference brake symbols
shall have the suffix ‘e’)
P = normal reaction of road surface on the axle under
static conditions
C = camshaft input torqueC
max= maximum technically permissible camshaft input
torque
C0= threshold camshaft input torque, i.e. minimum
camshaft torque necessary to produce a measurable
brake torque
R = tyre rolling radius(dynamic)
T = brake force at tyre/road interface
M = braking torque = T · Rz = braking rate
T
P¼M
RP
s = actuator stroke (working stroke plus free stroke)
Sp= effective stroke — the stroke at which the output
thrust is 90 % of the average thrust (ThA)
ThA= average thrust — the average thrust is determined by
integrating the valuesbetween one-third and two-thirds
of the total stroke (smax)
l = lever length
r = radiusof brake drump = brake actuation pressure
3. TEST METHODS
3.1. Tracktests
3.1.1. The brake performance tests should preferably be carried out on a
single axle only.
3.1.2. The results of tests on a combination of axles may be used in
accordance with item 1.1 provided that each axle contributes1971L0320 — EN — 03.01.1986 — 005.001 — 54
▼M4
equal braking energy input during the drag and residual brake
tests.
3.1.2.1. Thisisens ured if the following are identical for each axle: brake
geometry (Figure 2), lining, wheel mounting, tyres, actuation and
pressure distribution in the actuators.
3.1.2.2. The result recorded for a combination of axles will be the average
value for these axles.
3.1.3. The axle(s) should preferably be loaded with the maximum static
axle mass, though this is not essential provided that due allow-
ance ismade during the tes tsfor the difference in rolling
resistance caused by a different mass on the test axle(s).
3.1.4. Allowance shall be made for the effect of the increased rolling
resistance resulting from a combination of vehicles being used to
carry out the tests.
3.1.5. The initial speed of the test shall be prescribed. The final speed
shall be calculated by the following formula:
v2¼v1ﬃﬃﬃﬃﬃﬃﬃﬃﬃﬃﬃﬃﬃﬃﬃﬃﬃﬃﬃﬃﬃﬃﬃﬃﬃﬃ
P0þP1
P0þP1þP2r
where:
v1= initial speed (km/h)
v2= final speed (km/h)
Po= mass of the drawing vehicle (kg) under test conditions
P1= mass of the trailer borne by the non-braked axle(s) (kg)
P2= mass of the trailer borne by the braked axle (kg)
3.2. Inertiadynamometertests
3.2.1. The test machine shall have a rotary inertia simulating that part
of the linear inertia of the vehicle mass acting upon one wheel,
necessary for the cold performance and residual performance
tests, and capable of being operated at constant speed for the
purpose of the test described in items 3.5.2 and 3.5.3 below.
3.2.2. The test shall be carried out with a complete wheel, including the
tyre, mounted on the moving part of the brake, asit would be on
the vehicle. The inertia mass may be connected to the brake
either directly or via the tyresand wheels .
3.2.3. Air cooling at a velocity and air flow direction simulating actual
conditions may be used during the heating runs, the speed of air
flow being not greater than 10 km/h. The temperature of the
cooling air shall be the ambient temperature.
3.2.4. Where the tyre rolling resistance is not automatically compen-
sated for in the test, the torque applied to the brake shall be
modified by subtracting a torque equivalent to a rolling resistance
coefficient of 0,01.
3.3. Rollingroaddynamometertests
3.3.1. The axle should preferably be loaded with the maximum static
axle mass, though this is not essential provided that due allow-
ance ismade during the tes tsfor the difference in rolling
resistance caused by a different mass on the test axle.
3.3.2. Air cooling at a velocity and air flow direction simulating actual
conditions, may be used during the heating runs, the speed of air
flow being not greater than 10 km/h. The temperature of the
cooling air shall be the ambient temperature.
3.3.3. The braking time shall have a duration of 1 s after a maximum
build-up time of 0,6 s.
3.4. Testconditions
3.4.1. The test brake(s) shall be instrumented so that the following
measurements can be taken:
3.4.1.1. a continuousrecording to enable the brake torque or force at the
periphery of the tyre to be determined;1971L0320 — EN — 03.01.1986 — 005.001 — 55
▼M4
3.4.1.2. a continuous recording of air pressure in the brake actuator;
3.4.1.3. speed during the test;
3.4.1.4. initial temperature on the outside of the brake drum;
3.4.1.5. brake actuator stroke used during the Type O test and Type I and
II residual brake stops.
3.5. Testprocedures
3.5.1. Supplementary cold performance test
3.5.1.1. This test is carried out at an initial speed equivalent to 40 km/h in
order to evaluate the residual braking performance at the end of
the Type I and Type II tests.
3.5.1.2. Three brake applications are made at the same pressure (p) and at
an initial speed equivalent to 40 km/h, with an approximately
equal initial brake temperature not exceeding 100 ºC, measured
at the outside surface of the drum. The applications shall be at
the brake actuator pressure required to give a brake torque or
force equivalent to a braking rate (z) of at least 0,50. The brake
actuator pressure shall not exceed 6,5 bar, and the camshaft input
torque (C) shall not exceed the maximum technically permissible
camshaft input torque (Cmax). The average of the three results
shall be taken as the cold performance.
3.5.2. Type I test
3.5.2.1. This test is carried out at a speed equivalent to 40 km/h with an
initial brake temperature not exceeding 100 ºC, measured at the
outside surface of the drum.
3.5.2.2. A braking rate is maintained at 0,07 including the rolling resis-
tance (see item 3.2.4).
3.5.2.3. The duration of the test is 2 minutes and 33 seconds or 1,7 km at
40 km/h. If the test velocity cannot be achieved then the duration
of the test can be lengthened according to item 1.3.2.2 of Annex
II.
3.5.2.4. Not later than 60 seconds after the end of the Type I fade test, a
residual performance test is carried out in accordance with item
1.3.3 of Annex II at an initial speed equivalent to 40 km/h. The
brake actuator pressure shall be that used during the cold perfor-
mance test.
3.5.3. Type II test
3.5.3.1. This test is carried out at a speed equivalent to 30 km/h with an
initial brake temperature not exceeding 100 ºC, measured at the
outside surface of the drum.
3.5.3.2. A braking rate is maintained at 0,06 including the rolling resis-
tance (see item 3.2.4).
3.5.3.3. The duration of the test is 12 minutes or 6 km at 30 km/h.
3.5.3.4. Not later than 60 seconds after the end of the Type II fade test, a
residual performance test is carried out in accordance with item
1.4.3 of Annex II at an initial speed equivalent to 40 km/h. The
brake actuator pressure used shall be that used during the cold
performance test.
3.6. Testreport
3.6.1. The result of tests carried out in accordance with item 3.5 shall
be reported on a form, a model of which iss hown in Appendix
2 to thisAnnex.
3.6.2. The brake and the axle shall be identified. Particulars of the
brakes, the axle, the technically permissible mass and the number
of the corresponding test report shall be marked on the axle.
4. VERIFICATION4.1. Verificationofcomponents
The brake specification of the vehicle to be type approved shall
be verified by satisfying each of the following design criteria:1971L0320 — EN — 03.01.1986 — 005.001 — 56
▼M4
Item Criteria
4.1.1. (a) Brake drum cylindrical section No change allowed
(b) Brake drum material No change allowed
(c) Brake drum mass May change between − 0 and + 20 % of
the reference drum mass
4.1.2. (a) Proximity of wheel to outside surface
of brake drum (dimension E)/C148/C147/C147/C147/C147/C147/C147/C147/C147/C147/C147/C147/C147/C149/C147/C147/C147/C147/C147/C147/C147/C147/C147/C147/C147/C147/C150Tolerancesto be determined by the
technical service conducting the
approval tests(b) Part of brake drum not covered by
wheel (dimension F)
4.1.3. (a) Brake lining material/C148/C147/C147/C147/C147/C147/C147/C147/C147/C147/C147/C147/C147/C147/C147/C147/C147/C147/C147/C149/C147/C147/C147/C147/C147/C147/C147/C147/C147/C147/C147/C147/C147/C147/C147/C147/C147/C147/C150No change allowed(b) Brake lining width
(c) Brake lining thickness
(d) Brake lining actual surface
(e) Brake lining method of attachment
4.1.4. Brake geometry (figure 2) No change allowed
4.1.5. Tyre rolling radius(R) May change s ubject to the requirements
of item 4.3.5 of thisAppendix
4.1.6. (a) Average thrust (Th
A)/C148/C147/C147/C147/C147/C147/C147/C147/C147/C147/C147/C147/C147/C147/C149/C147/C147/C147/C147/C147/C147/C147/C147/C147/C147/C147/C147/C147/C150May change provided that the predicted
performance meetsthe requirementsof
item 4.3 of thisAppendix(b) Actuator stroke (s)
(c) Lever length
(d) Brake actuation pressure (p)
4.1.7. Static mass (P) P shall not exceed P
e
4.2. Verificationofbrakeforcesdeveloped
4.2.1. The brake forces (T) for each subject brake (for the same control
line pressure pm) necessary to produce the drag force specified for
both Type I and Type II test conditions are determined by the
method described in item 4.2.3.
4.2.2. For each axle, T shall not exceed X · Pe.
4.2.3. T 1¼X/C1PRmaxV1
V1þV2þV3
where:
X = 0,07 for the Type I and 0,06 for the Type II tests,
V = the value of any component that variesthe cams haft input
torque at each axle for a given control line pressure (pm)o r
the value of the actuator pressure at each axle (p) where it
is not common for a given control line pressure (pm).
Example:
Three-axled trailer having a PRmaxof 200 000 N where all compo-
nentsare identical except the brake lever lengthswhich are:
axle 1 = 152, axle 2 = 127, axle 3 = 127
then (for Type I) T1¼0;07/C1200000 /C1152
152þ127þ127
= 14 000 · 0,374 = 5 236 N
similary T2and T3¼0;07/C1200000 /C1127
152þ127þ127
= 14 000 · 0,313 = 4 382 N1971L0320 — EN — 03.01.1986 — 005.001 — 57
▼M4
4.3. Verificationofresidualperformance
4.3.1. The brake force (T) for each subject brake for a specified pres-
sure (p) in the actuators and control line pressure (pm) used
during the Type O test of the subject trailer is determined by the
methodsdes cribed in items4.3.2 to 4.3.5.
4.3.2. The predicted actuator stroke (s) of the subject brake is deter-
mined from the following relationship
s¼l/C1se
le
s shall not exceed the effective stroke (sp)
4.3.3. The average thrust output (ThA) of the actuator fitted to the
subject brake at the pressure specified in item 4.3.1. is deter-
mined.
4.3.3. The camshaft input torque (C) is then given by
C¼ThA/C1l:
C shall not exceed Cmax.
4.3.5. The predicted brake performance for the subject brake is given
by:
T¼Te/C1C/C0C0 ðÞ
Ce/C0C0e ðÞ/C1Re
R
R shall not be less than 0,8 Re.
4.3.6. The predicted brake performance for the subject trailer is given
by:
TR
PR¼ΣT
ΣP
4.3.7. The residual performances following the Type I and II tests shall
be determined in accordance with items4.3.2, 4.3.3, 4.3.4 and
4.3.5. The resulting predictions given by item 4.3.6 must satisfy
the requirementsof thisDirective for the s ubject trailer. The
value used for ‘the figure recorded in the Type O test’, as
prescribed in Annex II, item 1.3.3, shall be the figure recorded
in the Type O test of the subject trailer.1971L0320 — EN — 03.01.1986 — 005.001 — 58
▼M4
Appendix 2
MODEL REFERENCE AXLE TEST REPORT FORM AS PRESCRIBED IN APPENDIX 1,
ITEM3.6
1971L0320 — EN — 03.01.1986 — 005.001 — 59
▼M4
1971L0320 — EN — 03.01.1986 — 005.001 — 60
▼M4
Figure 2
BRAKEGEOMETRY
1971L0320 — EN — 03.01.1986 — 005.001 — 61
▼B
ANNEX VIII
CONDITIONSGOVERNINGTHETESTINGOFVEHICLESEQUIPPED
WITHINERTIA(OVERRUN)BRAKES
1. GENERAL PROVISIONS
1.1. The inertia (overrun) braking device of a trailer comprises the control
device, the transmission and the brakes proper, hereinafter called
‘brakes’.
1.2. The control device isthe combination of componentscompris ing the
coupling head.
1.3. The transmission is the combination of components comprised between
the coupling head and the first part of the brake.
1.4. The ‘brake’ isthe part in which the forcesoppos ing the movement of
the vehicle develop. The first part of the brake is either the lever
actuating the brake cam or similar parts (mechanical-transmission
inertia brake) or the brake cylinder (hydraulic-transmission inertia
brake).
1.5. Braking devicesin which accumulated energy (for ins tance, electric,
pneumatic or hydraulic) istrans mitted to the trailer by the drawing
vehicle and isonly controlled by the force at the coupling s hall not
be deemed to be inertia braking deviceswithin the meaning of this
Directive.
1.6. Two axles with a wheelbase of less than one metre (tandem axle) shall,
for the purposes of this Annex, also be deemed to be one axle.
1.7.Tests
1.7.1. Determination of the main characteristics of the brake.1.7.2. Determination of the main characteristics of the control device
and testing as to whether that device conforms with the provi-
sions of this Directive.
1.7.3. Testing on the vehicle
— the compatibility of the control device and the brake
— the transmission.
2. SYMBOLS AND DEFINITIONS
2.1.Unitsused
2.1.1.►
M3Masses ◄and
forces: ►M3Newton (N) ◄
2.1.2. Torquesand moments : ►M3Newton metre (Nm) ◄
2.1.3. Areas: cm2
2.1.4. Pressures: ►M3bar (bar) ◄
2.1.5. Lengths: units specified in each case.
2.2.Symbolsvalidforalltypesofbrakes (see diagram in Appendix 1, p.
771)
2.2.1. GA:‘►M3maximum mass ◄’ of the trailer declared to
be technically permissible by the manufacturer;
2.2.2. G ′A:‘►M3maximum mass ◄’ of the trailer which,
according to the manufacturer'sdeclaration, can be
braked by the control device;
2.2.3. GB:‘►M3maximum mass ◄’ of the trailer which can
be braked by the joint operation of all the trailer
brakes
GB¼n/C1GBo
2.2.4. GBo: Fraction of the permissible ‘ ►M3maximum
mass◄’ which, according to the manufacturer's
declaration, can be braked by one brake;
2.2.5. B*: braking force required;1971L0320 — EN — 03.01.1986 — 005.001 — 62
▼B
2.2.6. B: required braking force taking account of rolling resis-
tance;
2.2.7. D*: permitted thrust on coupling;2.2.8. D: load on the coupling;2.2.9. P ′: control device output force;
2.2.10. K: supplementary force of control device by convention;
thisisdefined asthe force D corres ponding to the
point of intersection of the x axes of the extrapolated
curve expressing P ′in termsof D, meas ured with the
control system in the mid-travel position (see graph in
Appendix 1, p. 772);
2.2.11. K
A: threshold force of control device—this is the
maximum force on the coupling head which can be
applied for a short period of time without producing
any output force on the control device. By convention,
KAisdefined asthe force meas ured when force begins
to be exerted on the coupling head at a speed of from
10 to 15 mm/s, the control device transmission being
uncoupled;
2.2.12. D1: thisisthe maximum force applied to the coupling
head when it isforced rearward at a s peed of smm/
s ± 10%, the transmission being uncoupled;
2.2.13. D2: thisisthe maximum force applied to the coupling
head when thisispulled forward at a s peed of smm/
s ± 10% from its rearmost position, the transmission
being uncoupled;
2.2.14. ηHo: efficiency of the inertia control device;
2.2.15. ηH1: efficiency of the transmission system;
2.2.16. ηH: total efficiency of the control device and of the trans-
mission
ηH¼ηHo/C1ηH1;
2.2.17. s: travel of control (expressed in millimetres);
2.2.18. s ′: effective travel of control (expressed in millimetres)
fixed in accordance with the requirementsof item
9.4.1;
2.2.19. s ′:►M4spare travel ◄of the master cylinder actuator,
measured in millimetres at the coupling head;
2.2.20. so: loss of travel, that is to say the travel, measured in
millimetres, of the coupling head when it is actuated
in such a way as to travel from a point 300 mm above
the horizontal plane to a point 300 mm below, the
transmission remaining stationary;
2.2.21. 2sB: brake-shoe lift measured on the diameter parallel to
the operating mechanism and without the brakes being
adjusted during the test (expressed in millimetres);
2.2.22. 2sB*: minimum brake-shoe lift (expressed in millimetres)
2sB/C3¼2/C14þ4
1000/C12r;
2r being the diameter of the brake drum expressed in
millimetres(s ee diagram in Appendix 1, p. 773);
2.2.23. M: braking moment;
2.2.24. R: radius of pneumatic tyres (in metres) measured under
load from wheel centre to ground level on the vehicle
being tested (rounded to the nearest centimetre);
2.2.24. n: number of brakes;
2.3.Symbols for mechanical transmission brakes (see diagram in
Appendix 1, p. 774)
2.3.1. iHo: reduction ratio between travel of the coupling head
and travel of the lever at the output side of the control
device;1971L0320 — EN — 03.01.1986 — 005.001 — 63
▼B
2.3.2. iH1: reduction ratio between travel of the lever at the
output side of the control device and travel of the
brake lever (gearing down of transmission);
2.3.3. iH: reduction ratio between travel of the coupling head
and travel of the brake lever
iH¼iHo/C1iH1;
2.3.4. ig: reduction ratio between travel of the brake lever and
the brake-shoe centre lift (see diagram in Appendix 1,
page 773);
2.3.5. P: force applied to the brake control lever;
2.3.6. Po: brake retraction force; that is, in the graph M = f (P),
the value of the force P at the point of intersection of
the extrapolation of this function with the abscissa (see
graph in Appendix 1, p. 775);
2.3.7. ρ: characteristic of the brake defined by: M ¼ρP/C0Po ðÞ
2.4.Symbols for hydraulic-transmission brakes (see diagram in
Appendix 1, p. 776).
2.4.1. ih: reduction ratio between travel of the coupling head
and travel of the piston in master cylinder;
2.4.2. ig′: reduction ratio between travel of the actuation point of
the cylindersand the brake-s hoe centre lift;
2.4.3. FRZ: surface area of piston in brake cylinder;
2.4.4. FHZ: surface area of piston in master cylinder;
2.4.5. p: hydraulic pressure in brake cylinder;
2.4.6. po: retraction pressure in brake cylinder; that is, in the
graph M = f(p), the value of the pressure p at the point
of intersection of the extension of this function with
the abscissa (see graph in Appendix 1, p. 775).
2.4.7. ρ′: characteristic of the brake defined by:
M¼ρ0p/C0po ðÞ :
3. GENERAL REQUIREMENTS
3.1. The transmission of braking power from the coupling head to the trai-
ler'sbrakesmus t be effected either by a rod linkage or by meansof
one or more fluids. However, a sheathed cable (Bowden cable) may
be used to provide part of the transmission. This part must be as short
as possible.
3.2. All pins at joints must be adequately protected. In addition, these joints
must be either self-lubricating or easily accessible for lubrication.
3.3 Inertia braking devices must be arranged in such a way that, in the case
where the coupling head travelsto itsfulles t extent, no part of the
transmission becomes jammed, or suffers any permanent distortion or
fails. This must be checked after uncoupling the first element of the
transmission from the brake control levers.
3.4. The inertia braking device must allow the trailer to be reversed with
the towing vehicle without imposing a sustained drag force exceeding
8 % of the force corresponding to the maximum mass of the trailer.
Devices used for this purpose must act automatically and disengage
automatically when the trailer movesforward.
3.5. Any special device incorporated for the purposes of item 3.4 shall be
such that the parking performance when facing up a gradient shall not
be adversely affected.
4. REQUIREMENTS FOR CONTROL DEVICES
4.1. The sliding members of the control device must be long enough to
enable the brake to be fully applied, even when the trailer iscoupled.
4.2. The sliding members must be protected by a bellows or some equiva-
lent device. They must either be lubricated or be constructed of self-
lubricating materials. The surfaces in frictional contact must be made1971L0320 — EN — 03.01.1986 — 005.001 — 64
▼M4
▼B
▼B
of a material such that there is neither electrochemical torque nor any
mechanical incompatibility liable to cause the sliding members to
seize.
►M44.3.◄The threshold force of the control equipment (KA) must be
not less than 0·02 G ′Aand not more than 0·04 G ′A.
4.4. The maximum depression force of D1may not exceed 0,10 G ′Ain the
case of single-axle trailers and 0,067 G ′Ain the case of multi-axle trai-
lers.
►M44.5.◄The maximum towing force D2must be between 0·1 G ′Aand
0·5 G′A.
5. TESTS AND MEASUREMENTS TO BE CARRIED OUT ON THE
CONTROL SYSTEM
5.1. Compliance with the requirementsof items3 and 4 above mus t be
verified on the control device submitted to the technical service
conducting the tests.
5.2. The following shall be measured in respect of all types of brakes:
5.2.1. the travel sand the available travel s ′;
5.2.2. the supplementary force K;
5.2.3. the threshold force KA;
5.2.4. the damping force D1;
5.2.5. the towing force D2.
5.3. In the case of mechanical-transmission inertia brakes, the following
shall be determined:
5.3.1. the reduction ratio iHo, measured at the mid-travel portion of the
control;
5.3.2. the force P ′at the output side of the control device as a function
of the thrust D on the drawbar.
The supplementary force K and the efficiency are derived from
the representative curve obtained from these measurements.
ηHo¼1
iHo/C1P0
D/C0K
(see graph in Appendix 1, p. 772)
5.4. In the case of hydraulic-transmission inertia brakes, the following shall
be determined:
5.4.1. the reduction ratio ihmeasured at the mid-travel position of the
control;
5.4.2. the pressure p at the output side of the master cylinder as a
function of the thrust D on the drawbar and of the surface area
FHZin the master cylinder piston, as specified by the manufac-
turer. The supplementary force K and the efficiency are derived
from the representative curve obtained from these measurements
ηHo¼1
ih/C1p/C1FHZ
D/C0K
(see graph in Appendix 1, page 772);
5.4.3. the ►M4spare travel ◄of the master cylinder actuator s ″
mentioned in item 2.2.19.
►M45.5.◄In the case of inertia brakes on multi-axle trailers, the loss
of travel somentioned in item 9.4.1 shall be measured.
6. REQUIREMENTS FOR BRAKES
6.1. The manufacturer must make available to the technical service respon-
sible for the tests, in addition to the brakes to be tested, drawings of1971L0320 — EN — 03.01.1986 — 005.001 — 65
▼M4
▼B
▼M4
▼B
▼M4
▼B
▼B
the brakes showing the type, dimensions and material of the main
parts, and the make and type of the linings. These drawings must indi-
cate the surface area FRZof the brake cylindersin the cas e of hydraulic
brakes. The manufacturer must also indicate the maximum braking
torque Mmaxwhich isallowed, aswell asthe ►M3mass◄GBomentioned in item 2.2.4.
6.2. The force P or the pressure p required to achieve the braking torque
Mmaxindicated by the manufacturer must be at least 1,8 times the force
P or at least 1,8 times the pressure p required to give a braking force of
0,50 GBO.
7. TESTS AND MEASUREMENTS TO BE CARRIED OUT ON THE
BRAKES
7.1. The brakesand itemsof equipment made available to the technical
service responsible for the tests must be tested to check whether theyconform to the requirementsof item 6.
7.2. The following shall be determined:
7.2.1. the minimum shoe centre lift 2s
B*;
7.2.2. the shoe centre lift 2sB(which must be greater than 2sB*);
7.2.3. the braking moment M asa function of the force P applied to
the control lever in the case of devices with mechanical trans-
mission, and of the pressure p in the brake cylinder in the case
of devices with hydraulic transmission.
The speed at which the braking surfaces rotate must correspond
to an initial vehicle speed of 60 km/h. The following shall be
deducted from the curve obtained from these measurements:
7.2.3.1. the retraction force P and the characteristic ρin the
case of mechanically actuated brakes (see graph in
Appendix 1, p. 775).
7.2.3.2. the retraction pressure poand the characteristic ρin the
case of hydraulically actuated brakes (see graph in
Appendix 1, p. 775).
8. TEST REPORTS
Where applicationsare made for type approval of trailersfitted with inertia
brakes, such applications are to be accompanied by the test reports relating
to the control system and the brakes, as well as the test report on the
compatibility between the inertia control device, the transmission and the
brakes on the trailer; these reports are to include at least the particulars
shown in Appendices 2, 3 and 4 to this Annex.
9. COMPATIBILITY OF THE CONTROL DEVICE AND THE INERTIA
BRAKES OF A VEHICLE
9.1. A check must be made on the vehicle, taking into account the charac-
teristics of the control device (Appendix 2) and of the brakes
(Appendix 3) aswell asthe trailer characteris ticsmentioned in item 4
of Appendix 4, asto whether the inertia braking device of the trailer
complieswith the requirementslaid down.
9.2.General testsforalltypesofbrakes
9.2.1. Those parts of the transmission which have not been tested at
the same time as the brake control device or the brakes must
be tested on the vehicle. The results of the test must be entered
in Appendix 4 (for example iH1andηH1).
9.2.2.►M3Mass◄
9.2.2.1. The ►M3maximum mass ◄of the trailer GAmust
not exceed the ►M3maximum mass ◄G′Afor which
the control device isauthoris ed.1971L0320 — EN — 03.01.1986 — 005.001 — 66
▼M4
▼B
▼M4
▼B
▼B
9.2.2.2. The ►M3maximum mass ◄of the trailer GAmust
not exceed the ►M3maximum mass ◄GBwhich
can be braked by the joint operation of all the trailer
brakes.
9.2.3.Forces
9.2.3.1. The threshold force KAmust not be less than 0·02 GAnor greater than 0·04 GA.
9.2.3.2. The maximum damping force D1must not exceed
0·09 GAin the case of single-axle trailers, nor 0·06 GAin the case of multi-axle trailers.
9.2.3.3. The maximum pulling force D2must be between 0·1 GAand 0·5 GA.
9.3.Testofbrakingefficiency
9.3.1. The sum of the braking forces exerted on the circumference of
the trailer wheels must be at least B* = 0,5 GA, including a
rolling resistance of 0,01 GA.
Thisrepres entsa braking force of B = 0,49 GA.
In this case, the maximum permitted thrust on the coupling shall
be:
D* = 0,067 GAin the case of multi-axle trailers,
D* = 0,10 GAin the case of single-axle trailers.
In order to check whether these conditions are observed, the
following inequalitiesmus t be applied:
9.3.1.1. In the case of inertia brakes with mechanical transmis-
sion:
B/C1R
ρþnPo/C20/C211
D/C3/C0K ðÞ /C1 ηH/C20iH
9.3.1.2. In the case of inertia brakes with hydraulic transmis-
sion:
B/C1R
n/C1ρ0þpo/C20/C211
D/C3/C0K ðÞ /C1 ηH/C20ih
FHZ
9.4.Controltraveltest
9.4.1. In the case of control devices for multi-axle trailers of which the
brake rod system is dependent upon the position of the towing
device, the travel of the control smus t be greater than the avail-
able travel of the control s ′; the difference in length must be at
least equivalent to the loss of travel so. The travel so, must not
exceed 10 % of the effective travel s ′.
9.4.2. The available travel of the control s ′shall be determined in the
following way:
9.4.2.1. if the brake rod system is affected by the relative posi-
tion of the towing device, then:
s0¼s/C0so;
9.4.2.2. if there isno los sof travel, then:
s0¼s;
9.4.2.3. in the case of hydraulic braking systems:
s0¼s/C0s00:
9.4.3. The following inequalitiess hall be applied in order to check
whether the travel of the control isadequate:1971L0320 — EN — 03.01.1986 — 005.001 — 67
▼M4
▼B
▼M4
▼B
▼M4
▼B
▼B
9.4.3.1. in the case of inertia brakes with mechanical transmis-
sion:
iH/C20s0
sB/C3/C1ig
9.4.3.2. in the case of inertia brakes with hydraulic transmis-
sion:
ih
FHZ/C20s0
2sB/C3/C1nFRZ/C1i0
g
9.5.Additionaltests
9.5.1. In the case of inertia brakes with mechanical transmission, a
check shall be made as to whether the rod system by which the
forcesare trans mitted from the control device iscorrectly fitted.
9.5.2. In the case of inertia brakes with hydraulic transmission, a check
shall be made as to whether the travel of the master cylinder
actuator reachesa minimum level of s /ih.
A lower level will not be permitted.
9.5.3. A road test must be carried out to determine the general reaction
of the vehicle to braking.
10. GENERAL COMMENTS
The above provisions apply to the latest models of inertia brakes with
mechanical or hydraulic transmission; in the case of these models, in parti-
cular, all the wheelsof the trailer are fitted with the s ame type of brake and
the same type of tyre.
When testing special models, the above requirements are to be adapted.1971L0320 — EN — 03.01.1986 — 005.001 — 68
▼B
Appendix 1
See 2.2
See 2.2.10 and 5.3.2 (devices with mechanical transmission)
1971L0320 — EN — 03.01.1986 — 005.001 — 69
▼B
See 2.2.10 and 5.4.2 (devices with hydraulic transmission)
1971L0320 — EN — 03.01.1986 — 005.001 — 70
▼B
See 2.2.22 and 2.3.4
Teststobecarried outonthebrakes1971L0320 — EN — 03.01.1986 — 005.001 — 71
▼B
Brakeswithmechanicaltransmission
See 2.3
1971L0320 — EN — 03.01.1986 — 005.001 — 72
▼B
See 2.3.6 and 7.2.3.1 (mechanical brake)
See 2.4.6 and 7.2.3.2 (hydraulic brake)
1971L0320 — EN — 03.01.1986 — 005.001 — 73
▼B
Brakeswithhydraulictransmission
See 2.4
1971L0320 — EN — 03.01.1986 — 005.001 — 74
▼B
Appendix 2
Testreportoninertia brakecontroldevice
►(1) (2)M3
►(3) (4)M41971L0320 — EN — 03.01.1986 — 005.001 — 75
▼B
Appendix 3
Braketestreport
►(1) (2) (3) (4)M3
►(5) (6) (7) (8) (9)M41971L0320 — EN — 03.01.1986 — 005.001 — 76
▼B
Appendix 4
Testreportonthecompatibilityoftheinertia controldevice,thetransmissionandthebrakesonthetrailer
►(1) (3)M3
►(2) (4)M41971L0320 — EN — 03.01.1986 — 005.001 — 77
▼B
►(1) (2) (3)M41971L0320 — EN — 03.01.1986 — 005.001 — 78
▼B
ANNEX IX
►M4a◄
►(1) (2) (3) (4)M3
►(5) (6)M41971L0320 — EN — 03.01.1986 — 005.001 — 79
▼B
►(1) (2) (3) (4) (5) (6)M31971L0320 — EN — 03.01.1986 — 005.001 — 80
▼M4
1971L0320 — EN — 03.01.1986 — 005.001 — 81
▼B
►(1)M2
►(2) (3) (4)M3
►(5) (6) (7) (8) (9) (10) (11) (12) (13) (14) (15) (16) (17)M41971L0320 — EN — 03.01.1986 — 005.001 — 82
▼M4
ANNEX X:REQUIREMENTSAPPLICABLETOTESTSFORVEHICLES
EQUIPPEDWITHANTI-LOCKDEVICES
1. GENERAL
1.1. The purpose of this Annex is to define the required performances
for braking systems with anti-lock devices fitted to road vehicles.
ThisAnnex doesnot make it compuls ory to fit vehicleswith anti-
lock devices, but if such devices are fitted to a road vehicle they
must meet the requirements of this Annex. In addition, motor
vehicleswhich are authorized to draw a trailer, and trailers
equipped with compressed-air braking systems, shall, when the
vehiclesare laden, meet the requirementsfor compatibility s et
out in the Appendix to item 1.1.4.2 of Annex II.
1.2. The devices known at present comprise a sensor or sensors, a
controller or controllersand a modulator or modulators . Any
devicesof a different des ign which may be introduced in the
future will be deemed to be anti-lock deviceswithin the meaning
of thisAnnex and the Appendix to item 1.1.4.2 of Annex II, if
they provide performances equal to those prescribed by this
Annex.
2. DEFINITIONS
2.1. An ‘anti-lock device’ is a component of a service braking system
which automatically controlsthe degree of s lip, in the direction of
rotation of the wheel(s), on one or more wheels of the vehicle
during braking.
2.2. ‘Sensor’ means a component designed to identify and transmit to
the controller the conditionsof rotation of the wheel(s ) or the
dynamic conditionsof the vehicle.
2.3. ‘Controller’ meansa component des igned to evaluate the data
transmitted by the sensor(s) and to transmit a signal to the modu-
lator.
2.4. ‘Modulator’ meansa component des igned to vary the braking
force(s) in accordance with the signal received from the
controller.
2.5. ‘Directly controlled wheel’ meansa wheel whos e braking force is
modulated according to data provided at least by its own
sensor(1).
2.6. ‘Indirectly controlled wheel’ meansa wheel whos e braking force
is modulated according to data provided by the sensor(s) of other
wheel(s) (1).
3. TYPES OF ANTI-LOCK DEVICE
3.1. A motor vehicle isdeemed to be equipped with an antilock
device within the meaning of paragraph 1 of the Appendix to
item 1.1.4.2 of Annex II, if one of the following devicesisfitted:
3.1.1. Category 1 anti-lock device:
A vehicle equipped with a category 1 anti-lock device shall meet
all the relevant requirementsof thisAnnex.
3.1.2. Category 2 anti-lock device:
A vehicle equipped with a category 2 anti-lock device shall meet
all the relevant requirementsof thisAnnex, except thos e of item
5.3.5.
3.1.3. Category 3 anti-lock device:
A vehicle equipped with a category 3 anti-lock device shall meet
all the relevant requirementsof thisAnnex, except thos e of items
5.3.4 and 5.3.5. On such vehicles, any individual axle (or bogie)
which doesnot include at leas t one directly controlled wheel
must fulfil the conditions of adhesion utilization and the wheel-
locking sequence of the Appendix to item 1.1.4.2 of Annex II,1971L0320 — EN — 03.01.1986 — 005.001 — 83
(1) Anti-lock deviceswith s elect-high control are deemed to include both directly and
indirectly controlled wheels; in devices with select-low control, all sensed wheels are
deemed to be directly controlled wheels.
▼M4
instead of the adhesion utilization requirements prescribed in item
5.2 of thisAnnex. However, if the relative pos itionsof the adhe-
sion utilization curves do not meet the requirements of item 3.1.1
of the Appendix to item 1.1.4.2 of Annex II, a check shall be
made to ensure that the wheels on at least one of the rear axles
do not lock before those on the front axle or axles under the
conditionspres cribed in items3.1.1 and 3.1.4 of the Appendix
to item 1.1.4.2 of Annex II with regard to the braking rate and
the load respectively. These requirements may be checked on
high- or low-adhesion road surfaces (about 0,8 and 0,3
maximum) by modulating the service brake control force.
3.2. A towed vehicle isdeemed to be equipped with an anti-lock
device within the meaning of item 1 of the Appendix to item
1.1.4.2 of Annex II, if it meetsall the relevant requirementsof
thisAnnex.
4. GENERAL REQUIREMENTS
4.1. Any break in the supply of electricity to the device and/or in the
wiring external to the elctronic controller(s) shall be signalled to
the driver by a specific optical warning signal. This requirement
also applies to the anti-lock device(s) of towed vehicles which are
designed to be coupled to towing vehicles of categories other
than M1and N1. The warning device for the anti-lock device(s)
of the towed vehicle must not give a signal when a towed vehicle
without an anti-lock device, or when no towed vehicle, is
coupled. Thisrequirement mus t be met automatically.
The warning signal shall light up when the anti-lock device is
energised and go off at the latest when the vehicle reaches a
speed of 10 km/h and no defect is present. The tell-tale lamps of
the warning devices must be visible even in daylight; it must be
easy for the driver to check that they are in working order(1).
4.2. Motor vehiclesequipped with anti-lock devicesand/or des igned
to tow a trailer equipped with such devices, with the exception
of vehiclesof categoriesM1and N1, shall be fitted with a separate
warning device for the anti-lock device(s) of the towed vehicle,
meeting the requirementsof item 4.1 above, or s hall be fitted
with an optical warning signal which shall light up not later than
any application of the brake to warn the driver if the attached
trailer isnot equipped with an anti-lock device. Thiswarning
signal shall be visible even in daylight and its good working
order shall be easily checked by the driver. It shall not convey
any signal if no trailer is attached. This function shall be auto-
matic (1).
4.3. Except for vehiclesof categoriesM1and N1, the electrical
connections used for the anti-lock devices of towed vehicles shall
be effected by a special connector conforming to ISO Standard
7638/1985 (1).
4.4. In the event of failure of the anti-lock device, the residual braking
performance must be that prescribed for the vehicle in question in
the event of failure of a part of the transmission to the servicebrake (see item 2.2.1.4 of Annex I). This requirement shall not
be construed as a departure from the requirements concerning
secondary braking.
4.5. The operation of the device must not be adversely affected by
magnetic or electrical fields(
2).1971L0320 — EN — 03.01.1986 — 005.001 — 84
(1) To ensure compatibility of all vehicles until the special ISO connector is in general use,
it shall be considered that the requirements of items 4.1, 4.2 and 4.3 concerning towed
vehicles are fulfilled only if the vehicles satisfy the following two conditions:1. the supply of electricity to the anti-lock device(s) of the towed vehicle is provided:
(a) firstly, via the ISO 3731 (24S) connector (using pins 2 and 6 for failure warning
and power supply, respectively) or via the special anti-lock connector
conforming to ISO 7638; and
(b) secondly, via the ISO 1185 (24N) connector (using pin 4 without exceeding the
present limits of the stop lamp circuit); if this is not fulfilled, the requirementsof the Appendix to item 1.1.4.2 of Annex II shall be satisfied: for example, bythe installation of a brake load sensing device on the towed vehicle;
2. the towed vehicle isequipped with an optical device, within the field of view of the
driver'srear view mirror and vis ible even in daylight, to warn him of any break inthe supply of electricity and/or in the wiring external to the electronic controller ofthe anti-lock device of the towed vehicle.
(
2) Until uniform test procedures have been agreed, the manufacturers shall provide the
Technical Services with their test procedures and results.
▼M4
5. SPECIAL PROVISIONS CONCERNING MOTOR VEHICLES
5.1. Energyconsumption
Braking systems equipped with anti-lock devices must maintain
their performance when the service brake is fully applied for
long periods. Compliance with this requirement shall be verified
by means of the following tests:
5.1.1. Test procedure
5.1.1.1. The initial energy level in the energy storage device(s) shall be
that specified by the manufacturer. This level shall be at least
such as to ensure the efficiency prescribed for service braking
when the vehicle is laden. The auxiliary service storage device(s)
must be isolated.
5.1.1.2. From an initial speed of not less than 50 km/h, on a surface with
a coefficient of adhesion of 0,3(1) or less, the brakes of the laden
vehicle shall be fully applied for a time t, and all the wheels
equipped with an anti-lock device must remain under control
throughout that time.
5.1.1.3. The vehicle's engine shall then be stopped or the supply to the
energy storage device(s) cut off.
5.1.1.4. The service brake control shall then be fully actuated four times
in succession with the vehicle stationary.
5.1.1.5. When the brakes are applied for the fifth time, it must be possible
to brake the vehicle with at least the performance prescribed for
secondary braking of the laden vehicle.
5.1.1.6. During the tests, in the case of a motor vehicle authorized to
draw a trailer equipped with a compressed air braking system,
the supply line shall be stopped and an energy storage device of
0,5-litre capacity shall be connected to the control line (in accor-
dance with Annex IV, item 1.2.2.3). When the brakesare applied
for the fith time, asprovided in item 5.1.1.5, the energy level
supplied to the control line must not be below half the level
obtained at a full application starting with the initial energy level.
5.1.2. Additional requirements
5.1.2.1. The coefficient of adhesion of the road surface shall be measured
with the vehicle in question, by the method described in item 1.1
of Appendix 1 to thisAnnex.
5.1.2.2. The braking test shall be conducted with the engine disconnected
and idling, and with the vehicle laden.
5.1.2.3. The braking time t shall be determined by the formula: t ¼Vmax
7
(but not less than 15 seconds) where t is expressed in seconds and
Vmaxrepresents the maximum design speed of the vehicle
expressed in km/h, with an upper limit of 160 km/h.
5.1.2.4. If the time t cannot be completed in a single braking phase,
further phases may be used, up to a maximum of four in all.
5.1.2.5. If the test is conducted in several phases, no fresh energy shall be
supplied between the phases of the test.
5.1.2.6. The performance prescribed in item 5.1.1.5 shall be deemed to be
satisfied if, at the end of the fourth application, with the vehicle
stationary, the energy level in the storage device(s) is at or above
that required for secondary braking with the laden vehicle.
5.2. Utilizationofadhesion
5.2.1. The utilization of adhesion by the anti-lock device takes into
account the actual increase in braking distance beyond the theore-
tical minimum. The anti-lock device shall be deemed to be
satisfactory when the condition ε≥0,75 is satisfied, where ε
represents the adhesion utilized, as defined in item 1.2 of
Appendix 1 to thisAnnex. Thisrequirement s hall not be1971L0320 — EN — 03.01.1986 — 005.001 — 85
(1) Until such test surfaces become generally available, tyres at the limit of wear, and
higher values up to 0,4 may be used at the discretion of the technical services. The
actual value obtained and the type of tyres and surface shall be recorded.
▼M4
construed as requiring a braking performance better than that
prescribed in Annex II for the vehicle in question.
5.2.2. The adhesion utilization εshall be measured on road surfaces
with a coefficient of adhesion of 0,3(1) or less, and of about 0,8
(dry road), with an initial speed of 50 km/h.
5.2.3. The test procedure to determine the coefficient of adhesion (K)
and the formulae for calculation of the adhesion utilization ( ε)
shall be those laid down in Appendix 1 to this Annex.
5.2.4. The utilization of adhesion by the anti-lock device shall be
checked on complete vehiclesequipped with anti-lock devicesof
categories1 or 2. In the cas e of vehiclesequipped with category
3 anti-lock devices, only the axle(s) with at least one directly
controlled wheel must satisfy this requirement.
5.2.5. The condition ε≥0,75 shall be checked with the vehicle laden
and unladen.
5.3. Additionalchecks
The following additional checkss hall be carried out with the
vehicle laden and unladen.
5.3.1. The wheelsdirectly controlled by an anti-lock device mus t not
lock when the full force(2) iss uddenly applied on the control
device, on the two kinds of road surface specified in item 5.2.2
above, at low initial speeds V = 40 km/h and at high initial
speeds V ≈0,8 Vmax≤120 km/h.
5.3.2. When an axle passes from a high-adhesion surface (K1) to a low-
adhesion surface (K2) where K1≥0,5 and K1/K2≥2(3), with
the full force (2) applied on the control device, the directly
controlled wheels must not lock. The running speed and the
instant of applying the brake shall be so calculated that, with the
anti-lock device fully cycling on the high-adhesion surface, the
passage from one surface to the other is made at high and at
low speed, under the conditions laid down in item 5.3.1 above.
5.3.3. When a vehicle passes from a low-adhesion surface (K2)t oa
high-adhesion surface (K1) where K1≥0,5 and K1/K2≥2,
with the full force (2) applied on the control device, the decelera-
tion of the vehicle must rise to the appropriate high value within
a reasonable time and the vehicle must not deviate from its initial
course. The running speed and the instant of applying the brake
shall be so calculated that, with the anti-lock device fully cycling
on the low-adhesion surface, the passage from one surface to the
other occursat approximately 50 km/h.
5.3.4. The provisions of this paragraph shall only apply to vehicles
equipped with anti-lock devicesof categories1 or 2. When the
right and left wheels of the vehicle are situated on surfaces with
differing coefficientsof adhes ion (K1and K2), where K1≥0,5
and K1/K2≥2, the directly controlled wheelsmus t not lock
when the full force (2) iss uddenly applied on the control device
at a speed of 50 km/h.
5.3.5. Furthermore, laden vehiclesequipped with anti-lock devicesof
category 1 shall, under the conditions of item 5.3.4 above, satisfy
the prescribed braking rate in Appendix 2 to this Annex.
5.3.6. However, in the tests provided for in items 5.3.1, 5.3.2, 5.3.3,
5.3.4 and 5.3.5 above, brief periodsof wheel-locking s hall be
allowed. Furthermore, wheel-locking ispermitted when the
vehicle speed is less than 15 km/h; likewise, locking of indirectly
controlled wheels is permitted at any speed, but stability and
steerability must not be affected.
5.3.7. During the tests provided for in items 5.3.4 and 5.3.5 above,
steering correction is permitted if the angular rotation of the
steering control is within 120º during the initial 2 seconds and
not more than 240º in all. Furthermore, at the beginning of these1971L0320 — EN — 03.01.1986 — 005.001 — 86
(1) See footnote to item 5.1.1.2.
(2) ‘Full force’ meansthe maximum force pres cribed in Annex II for the category of
vehicle; a higher force may be used if required to activate the anti-lock device.
(3)K1is the high-adhesion surface coefficient.
K2is the low-adhesion surface coefficient.
K1and K2are measured as laid down in Appendix 1 to this Annex.
▼M4
tests the longitudinal median plane of the vehicle must pass over
the boundary between the high- and low-adhesion surfaces and
during these tests no part of the (outer) tyres must cross this
boundary.
6. SPECIAL PROVISIONS CONCERNING TOWED VEHICLES6.1. Energyconsumption
Braking systems equipped with anti-lock devices shall be so
designed that, even after the service braking control has been
fully applied for some time, the vehicle retains sufficient energy
to bring it to a halt within a reasonable distance.
6.1.1. Compliance with the above requirement shall be checked by the
procedure specified below, with the vehicle unladen, on a straight
and level road with a surface having a good coefficient of adhe-
sion(
1), and with the brakes adjusted as closely as possible and
with the proportioning/load-sensing valve (if fitted) held in the
‘laden’ position throughout the test.
6.1.2. The initial energy level in the energy storage device(s) shall be
the maximum specified by the vehicle manufacturer; in the case
of a standard assembly as referred to in item 3.1.2 of the
Appendix to item 1.1.4.2 of Annex II, the initial energy level
shall be equivalent to a pressure of 8 bar at the coupling head of
the trailer'ss upply line.
6.1.3. The brakes shall be fully applied for a time t = 15 seconds,
during which all wheelsequipped with an antilock device mus t
remain under control. During this test, the supply to the energy
storage device(s) shall be cut off.
6.1.4. If the axle or axlesequipped with an anti-lock device receive
energy from an energy storage device or devices shared with
another axle or axlesnot equipped with an anti-lock device, the
supply to the axle or axles not so equipped may be cut off during
braking. However, the consumption of energy corresponding to
the initial application of the brakeson that axle or axless hall be
taken into account.
6.1.5. At the end of the braking, with the vehicle stationary, the service
braking control shall be fully actuated four times. During the fifth
application, the pressure in the operating circuit must be suffi-
cient to provide a total braking force at the periphery of the
wheels equal to not less than 22,5 % of the force corresponding
to the maximum mass borne by the wheels when the vehicle is
stationary.
6.2. Utilizationofadhesion
6.2.1. Braking systems equipped with an anti-lock device shall be
deemed acceptable when the condition ε≥0,75 is satisfied,
where εrepresents the adhesion utilized, as defined in item 2 of
Appendix 1 to thisAnnex. Thiscondition s hall be verified with
the vehicle unladen, on a straight and level road with a surface
having a good coefficient of adhesion (1)
6.3. Additionalchecks
6.3.1. At speeds exceeding 15 km/h, the wheels directly controlled by
an anti-lock device must not lock when the full force is suddenly
applied on the control device. Thiss hall be checked, under the
conditions prescribed in item 6.2 above, at a low initial speed
V = 40 km/h and at a high initial speed V ≈80 km/h.
6.3.2. Brief periodsof locking of the wheelss hall, however, be allowed,
but stability must not be affected.1971L0320 — EN — 03.01.1986 — 005.001 — 87
(1) If the coefficient of adhesion of the test track is too high, preventing the anti-lock
device from cycling, then the test may be carried out on a surface with a lower coeffi-
cient of adhesion.
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Appendix 1
UTILIZATIONOFADHESION
1. METHOD OF MEASUREMENT FOR MOTOR VEHICLES
1.1. Determinationofthecoefficient ofadhesion(K)
1.1.1. The coefficient of adhesion (K) shall be determined as the
quotient of the maximum braking forceswithout locking the
wheelsand the corres ponding dynamic load on the axle being
braked.
1.1.2. The brakess hall be applied on only one axle of the vehicle under
test, at an initial speed of 50 km/h. The braking forces shall be
equally distributed between the wheels of the axle. The anti-lock
device shall be disconnected.
1.1.3. A number of tests at increments of line pressure shall be carried
out to determine the maximum braking rate of the vehicle (zm).
During each test, a constant input force shall be maintained and
the braking rate will be determined by reference to the time taken
(t) for the speed to reduce from 40 km/h to 20 km/h using the
formula:
z¼0;56
t
zmis the maximum value of z; t is in seconds.
1.1.4. The braking forces shall be calculated from the measured braking
rate and the rolling resistance of the unbraked axle(s) which is
equal to 0,015 and 0,010 of the static axle load for a driven axle
and a non-driven axle, respectively.
1.1.5. The dynamic load on the axle shall be that given by the relations
in the Appendix to item 1.1.4.2 of Annex II.
1.1.6. The value of K shall be rounded to the second place of decimals.1.1.7. Example: in the case of a two-axle vehicle, with the front axle (1)
being braked, the coefficient of adhesion (K) is given by:
K¼
zm/C1P/C00;015/C1P2
P1þh
E/C1zm/C1P:
The other symbols (P, h, E) are defined in the Appendix to item
1.1.4.2 of Annex II.
1.2. Determinationoftheadhesionutilized( ε)
1.2.1. The adhesion utilized ( ε)isdefined asthe quotient of the
maximum braking rate with the anti-lock device in operation
(zmax) and the coefficient of adhesion (K) i.e.
ε¼zmax
K
1.2.2. The maximum braking rate (zmax) shall be measured with the anti-
lock device in operation and based on the average value of three
tests, using the time taken for the speed to reduce from 40 km/h
to 20 km/h asin item 1.1.3 above.
1.2.3. The value of εshall be rounded to the second place of decimals.
1.2.4. In the case of a vehicle equipped with an anti-lock device of cate-
gories1 or 2, the value of zmaxwill be based on the whole
vehicle, with the anti-lock device in operation, and the adhesion
utilized ( ε)isgiven by the s ame formula quoted in item 1.2.1
above.
1.2.5. In the case of a vehicle equipped with an anti-lock device of cate-
gory 3, the value of zmaxwill be measured on each axle which has
at least one directly controlled wheel.1971L0320 — EN — 03.01.1986 — 005.001 — 88
▼M4
Example: for a two-axle vehicle with an anti-lock device acting
only on the rear axle (2), the adhesion utilized ( ε)isgiven by:
ε¼zmax/C1P/C00;010/C1P1
K/C1P2/C0h
E/C1zmax/C1P/C18/C19 :
This calculation shall be made for each axle having at least one
directly controlled wheel.
2. METHOD OF MEASUREMENT FOR TOWED VEHICLES
2.1. Where all the axleshave at leas t one directly controlled wheel:
2.1.1. The test shall be conducted by braking one axle at a time; the
other axless hall not be braked and the engine of the towing
vehicle shall be disconnected.
2.1.2. The mean braking rate (z) shall be determined, taking into
account the rolling resistance of the unbraked axles. The test shall
be conducted at a speed of 50 km/h and the rolling resistance
coefficient may be estimated at 0,01.
2.1.3. The following relation shall be verified for each axle:
ε¼z1
z0/C210;75
where:
ε= the adhesion utilized,
z0= the maximum braking rate obtained by braking one axle
without locking the wheels, the anti-lock device being
disconnected,
z1= the braking rate obtained by braking the same axle on the
same road surface, with the anti-lock device in operation.
The valuesto be us ed for z1and z0shall be the arithmetic means
of three values measured in succession under the same test condi-
tions.
2.2. Where not all axleshave at leas t one directly controlled wheel:2.2.1. In the case of full trailers, the coefficient of adhesion (K) and the
adhesion utilized ( ε)shall be determined in accordance with the
provis ionsfor motor vehiclesin items1.1 and 1.2 of this
Appendix. The forcesin the drawbar connection s hall be taken
into account.
2.2.2. In the case of semi-trailers (and centre-axle trailers), the
following procedure shall be used:
2.2.2.1. The adhesion utilized shall be calculated by means of the
formula:
ε¼
zmax
z0
where:
z0= the maximum braking rate obtained by braking one
axle without locking the wheels, the anti-lock device
being disconnected and the wheels of the other axles
removed,
zmax= the braking rate obtained by braking all the axles
controlled by the anti-lock device, with the device in
operation.
2.2.2.2. The value of z0may be calculated by carrying out the procedure
described in item 1.1.3 of this Appendix to determine the
maximum braking rate (z*).
Then : z 0¼TR
PRdyn;1971L0320 — EN — 03.01.1986 — 005.001 — 89
▼M4
where:
TR = braking force = z* · (P + PM) − 0,01 · W
PRdyn= dynamic load ¼PR/C0TR/C1hsþP/C1z/C3hR/C0hs ðÞ
ER
and W is the static mass of the unbraked axles.
The other symbols are defined in the appendix to item 1.1.4.2 of
Annex II.
2.2.2.3. The value of zmaxmay be calculated by the same procedure:
measure z**, the braking rate with the anti-lock device in opera-
tion; calculate TR ′and PR′dynusing the formulae in item 2.2.2.2
above, and then
zmax¼TR0
PR0
dyn1971L0320 — EN — 03.01.1986 — 005.001 — 90
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Appendix 2
PERFORMANCEONDIFFERING-ADHESIONSURFACES
1. The prescribed braking rate referred to in item 5.3.5 of this
Annex may be calculated by reference to the measured coeffi-
cient of adhesion of the two surfaces on which this test is
carried out.
These two surfaces must satisfy the conditions prescribed in item
5.3.4 of thisAnnex.
2. The coefficient of adhesion (K1and K2) of the high- and low-
adhesion surfaces, respectively, shall be determined in accordance
with the provisions in item 1.1 of Appendix 1 to this Annex.
3. The prescribed braking rate (z3) for laden motor vehicless hall be:
z3/C210;75/C14K2þK1
5/C18/C19
and z 3/C21K2:1971L0320 — EN — 03.01.1986 — 005.001 — 91
▼M4
ANNEX XI:TEST CONDITIONS FOR TRAILERS WITH ELECTRICAL
BRAKINGSYSTEMS
1. GENERAL
1.1. For the purposes of the following provisions electrical brakes are
service braking systems consisting of a control device, an electro-
mechanical transmission device, and friction brakes. The
electrical control device regulating the voltage for the trailer
must be situated on the trailer.
1.2. The electrical energy required for the electrical braking system is
supplied to the trailer by the motor vehicle.
1.3. Electrical braking systems shall be actuated by operating the
service braking system of the motor vehicle.
1.4. The nominal voltage rating shall be 12 V.1.5. The maximum current consumption shall not exceed 15 A.1.6. The electrical connection of the electrical braking system to the
motor vehicle shall be effected by means of a special plug andsocket connection corresponding to …(
1), the plug of which shall
not be compatible with the sockets of the lighting equipment of
the vehicle. The plug together with the cable shall be situated on
the trailer.
2. CONDITIONS CONCERNING THE TRAILER
2.1. If there isa battery on the trailer fed by the power s upply unit of
the motor vehicle, it shall be separated from its supply line during
service braking of the trailer.
2.2. With trailers whose unladen mass is less than 75 % of their
maximum mass the braking force shall be automatically regulated
asa function of the loading condition of the trailer.
2.3. Electrical braking devices shall be such that even if the voltage in
the connection linesisreduced to a value of 7 V a braking effect
of 20 % of the force corresponding to the maximum mass of the
trailer ismaintained.
2.4. Control devicesfor regulating the braking force, which react to
the inclination in the direction of travel (pendulum, spring-mass-
system, liquid-inertia-switch) shall, if the trailer has more than
one axle and a vartically adjustable towing device, be attached
to the chassis. In the case of single-axle trailers and trailers with
close-coupled axles where the axle spread is less than 1 metre,
these control devices shall be equipped with a mechanism indi-
cating its horizontal position (e.g. spirit level) and shall be
manually adjustable to allow the mechanism to be set in the hori-
zontal plane in line with the direction of travel of the vehicle.
2.5. The relay for actuating the braking current in accordance with
item 2.2.1.20.2 of Annex I, which isconnected to the actuating
line, shall be situated on the trailer.
2.6. A dummy socket shall be provided for the plug.2.7. A tell-tale shall be provided at the control device, lighting up at
any brake application and indicating the proper functioning of the
trailer electric braking system.
3. PERFORMANCE
3.1. Electrical braking systems shall respond at a deceleration of the
tractor/trailer combination of not more than 0,4 m/s
2.
3.2. The braking effect may commence with an initial braking force,
which shall not be higher than 10 % of the force corresponding to
the maximum mass nor higher than 13 % of the force corre-
sponding to the unladen mass of the trailer.
3.3. The braking forces may also be increased in steps. At higher
levelsof the braking forcesthan thos e referred to in item 3.21971L0320 — EN — 03.01.1986 — 005.001 — 92
(1) Under study. Until the characteristics of this special connection have been determined,
the type to be used will be indicated by the national authority granting the approval.
▼M4
these steps shall not be higher than 6 % of the force corre-
sponding to the maximum mass, nor higher than 8 % of the
force corresponding to the unladen mass of the trailer. However,
in the case of single-axle trailers having a maximum mass not
exceding 1,5 tonnes, the first step must not exceed 7 % of the
force corresponding to the maximum mass of the trailer. An
increase of 1 % of this value is permitted for the subsequent steps
(example: first step 7 %, second step 8 %, third step 9 %, etc.;
any further step should not exceed 10 %). For the purpose of
these provisions a two-axle trailer having a wheelbase shorter
than 1 metre will be considered as a single-axle trailer.
3.4. The prescribed braking force of the trailer of at least 50 % of the
force corresponding to its maximum mass shall be attained —
with maximum mass — in the case of a mean fully developed
deceleration of the tractor/trailer combination of not more than
5,9 m/s2with single-axle trailers and of not more than 5,6 m/s2
with multi-axle trailers. Trailers with close-coupled axles wherethe axle spread is less than 1 metre are also considered as
single-axle trailers within the meaning of this provision. More-
over, the limitsasdefined in the Appendix to thisAnnex mus t
be observed. If the braking force is regulated in steps, they shall
lie within the range shown in the Appendix to this Annex.
3.5. The test shall be carried out with an initial speed of 60 km/h.3.6. Automatic braking of the trailer shall be provided in accordance
with the conditionsof item 2.2.2.9 of Annex I. If thisautomatic
braking action requireselectrical energy, a trailer braking force of
at least 25 % of the force corresponding to its maximum mass
shall be guaranteed for at least 15 minutes to satisfy the above-
mentioned conditions.1971L0320 — EN — 03.01.1986 — 005.001 — 93
▼M4
Appendix
Compatibilityofthebrakingrateofthetrailerandthemeanfullydevelopeddecelerationofthe
tractor/trailer combination(trailer ladenandunladen)
Notes:
1. Limits indicated in the diagram refer to laden and unladen trailers. When the trailer unladen mass
exceeds 75 % of its maximum mass, limits shall be applied only to ‘laden’ conditions.
2. Limitsindicated in the diagram do not affect the provis ionsof thisAnnex regarding the minimum
braking performancesrequired. However, if braking performancesobtained during tes t — in accor-
dance with provisions indicated in item 3.4 above — are greater than those requested, do not
exceed the limitsindicated in the above diagram.
TR = sum of braking forces at periphery of all wheels of trailer.
PR = total normal static reaction of road surface on wheels of trailer.
J = mean fully developed deceleration of tractor/trailer combination.1971L0320 — EN — 03.01.1986 — 005.001 — 94
▼M4
ANNEX XII: INERTIA DYNAMOMETER TEST METHOD FOR BRAKE
LININGS
1. GENERAL
1.1. The procedure described in this Annex may be applied in the
event of a modification of vehicle-type resulting from the fitting
of brake liningsof another type to vehicleswhich have been
approved in accordance with thisDirective.
1.2. The alternative typesof brake liningss hall be checked by
comparing their performance with that obtained from the brake
liningswith which the vehicle wasequipped at the time of
approval and conforming to the componentsidentified in the rele-
vant information document, a model of which isgiven in Annex
IX.
1.3. The technical authority responsible for conducting approval tests
may at its discretion require comparison of the performance of
the brake liningsto be carried out in accordance with the relevant
provisions contained in Annex II.
1.4. Application for approval by comparison shall be made by the
vehicle manufacturer or by hisduly accredited repres entative.
1.5. In the context of thisAnnex ‘vehicle’ s hall mean the vehicle-type
approved according to thisDirective and for which it isreques ted
that the comparison shall be considered satisfactory.
2. TEST EQUIPMENT
2.1. A dynamometer having the following characteristics shall be
used:
2.1.1. it shall be capable of generating the inertia required by item 3.1
of thisAnnex, and have the capacity to meet the requirements
prescribed by items 1.3 and 1.4 of Annex II with respect to
Type I and II fade tests;
2.1.2. the brakes fitted shall be identical with those of the original
vehicle-type concerned;
2.1.3. air cooling, if provided, shall be in accordance with item 3.4 of
thisAnnex;
2.1.4. the instrumentation for the test shall be capable of providing at
least the following data:
2.1.4.1. a continuous recording of disc or drum rotational speed;2.1.4.2. number of revolutions completed during a stop, to resolution not
greater than one-eighth of a revolution;
2.1.4.3. stop time;2.1.4.4. a continuousrecording of the temperature meas ured in the centre
of the path swept by the lining or at mid-thickness of the disc or
drum or lining;
2.1.4.5. a continuous recording of brake application control line pressure
or force;
2.1.4.6. a continuousrecording of brake output torque.
3. TEST CONDITIONS
3.1. The dynamometer shall be set as close as possible, with ± 5 %
tolerance, to the rotary inertia equivalent to that part of the total
inertia of the vehicle braked by the appropriate wheel(s)
according to the following formula:
I¼MR
2
Where:
I = rotary inertia (kgm2)
R = tyre rolling radius(m)
M = that part of the maximum mass of the vehicle braked by
the appropriate wheel(s). In the case of a single-ended
dynamometer, this mass shall be calculated from the
design braking distribution when deceleration corresponds1971L0320 — EN — 03.01.1986 — 005.001 — 95
▼M4
to the appropriate value given in item 2.1.1.1.1 of Annex
II, except in the case of category O trailers when the value
of M will be equivalent to the mass on the ground for the
appropriate wheel when the vehicle iss tationary and
loaded to its maximum mass.
3.2. The initial rotational speed of the inertia dynamometer shall
correspond to the linear speed of the vehicle as prescribed in
this Directive and shall be based on the rolling radius of the tyre.
3.3. Brake linings shall be at least 80 % bedded and shall not have
exceeded a temperature of 180 ºC during the bedding procedure,
or alternatively, at the vehicle manufacturer'sreques t, be bedded
in accordance with hisrecommendations .
3.4. Cooling air may be used, flowing over the brake in a direction
perpendicular to itsaxisof rotation. The velocity of the cooling
air flowing over the brake shall be not greater than 10 km/h.
The temperature of the cooling air shall be the ambient tempera-
ture.
4. TEST PROCEDURE
4.1. Five sample sets of the brake lining shall be subjected to the
comparison test; they shall be compared with five sets of linings
conforming to the original componentsidentified in the informa-
tion document concerning the first approval of the vehicle-type
concerned.
4.2. Brake lining equivalence shall be based on a comparison of the
results achieved using the test procedures prescribed in this
Annex and in accordance with the following requirements:
4.3. TypeOcoldperformancetest
4.3.1. Three brake applicationss hall be made when the initial tempera-
ture is below 100 ºC. The temperature shall be measured in
accordance with the provisions of item 2.1.4.4.
4.3.2. In the case of brake linings intended for use on vehicles of cate-
goriesM and N, brake applicationss hall be made from an initial
rotational speed equivalent to that given in item 2.1.1.1.1 of
Annex II and the brake shall be applied to achieve a mean torque
equivalent to the declaration prescribed in that item. In addition,
tests shall be carried out at several rotational speeds, the lowest
being equivalent to 30 % of the maximum speed of the vehicle
and the highest being equivalent to 80 % of that speed.
4.3.3. In the case of brake linings intended for use on vehicles of cate-
gory O, brake applicationss hall be made from an initial rotational
speed equivalent to 60 km/h, and the brake shall be applied to
achieve a mean torque equivalent to that prescribed in item 2.2.1
of Annex II. A supplementary cold performance test from an
initial rotational speed equivalent to 40 km/h shall be carried out
for comparison with the Type I and II test results as described in
item 2.2.1.2.1 of Annex II.
4.3.4. The mean braking torque recorded during the above cold perfor-
mance tests on the linings being tested for the purpose of
comparison shall, for the same input measurement, be within the
test limits ± 15 % of the mean braking torque recorded with the
brake liningsconforming to the component indentified in the
relevant application for vehicle type approval.
4.4. TypeItest:
4.4.1. With repeated braking
4.4.1.1. Brake linings for vehicles of category M and N shall be tested
according to the procedure given in paragraph 1.3.1 of Annex II.
4.4.2. With continuous braking
4.4.2.1. Brake linings for trailers of category O shall be tested in accor-
dance with item 1.3.2 of Annex II.
4.4.3. Residual performance
4.4.3.1. On completion of the tests required under item 4.4.1 and 4.4.2
above, the residual braking performance test specified in item
1.3.3 of Annex II shall be carried out.1971L0320 — EN — 03.01.1986 — 005.001 — 96
▼M4
4.4.3.2. The mean braking torque recorded during the above residual
performance tests on the linings being tested for the purpose of
comparison shall, for the same input measurement, be within the
test limits ± 15 % of the mean braking torque recorded with the
brake liningsconforming to the component identified in the rele-
vant application for vehicle type approval.
4.5. TypeIItest
4.5.1. This test is required only if, on the vehicle type in question, the
friction brakes are used for the Type II test.
4.5.2. Brake liningsfor motor vehiclesof category M3(except those
required under item 2.2.1.19 of Annex I to undergo a Type II A
test) and category N3, and trailersof category O4shall be tested
according to the procedure set out in item 1.4.1 of Annex II.
4.5.3. Residual performance
4.5.3.1. On completion of the test required under item 4.5.2 above, the
residual performance test specified in item 1.4.3 of Annex II shall
be carried out.
4.5.3.2. The mean braking torque recorded during the above residual
performance tests on the linings being tested for the purpose of
comparison shall, for the same input measurement, be within the
test limits ± 15 % of the mean braking torque recorded with the
brake liningsconforming to the component identified in the rele-
vant application for type approval.
5. INSPECTION OF BRAKE LININGS
5.1. Brake linings shall be visually inspected on completion of the
tests outlined above to check that they are in satisfactory condi-
tion for continued use in normal service.1971L0320 — EN — 03.01.1986 — 005.001 — 97