Legalize / European Union / Delegated Regulation

Commission Delegated Regulation (EU) 2015/68 of 15 October 2014 supplementing Regulation (EU) No 167/2013 of the European Parliament and of the Council with regard to vehicle braking requirements for the approval of agricultural and forestry vehicles Text with EEA relevance

Type Delegated Regulation

Publication 2015-01-23

Last updated 2025-06-15

State In force

Department European Commission

Source EUR-Lex

articles 19

Reform history JSON API

5.2.1.2. The performance of the service braking system required under the Regulation shall be obtained by the actuation of a single control device.

5.2.1.2.1. This requirement is also deemed to be satisfied when the foot is moved from the drive pedal to the brake pedal or when at the start of the braking sequence, the drive control device is released or moved to neutral position by hand or foot.

5.2.1.2.2. The control device of the service braking system shall be designed to return to the initial position automatically when released.

This does not apply to the hydrostatic section of the braking system when the release of the hydrostatic drive control device creates the braking effect.

5.2.1.3. Contrary to point 5.2.1.1, with vehicles of Class I and Class II, when braking with the service brake system another brake system may also be used (secondary or parking braking system) to bring the vehicle to a stop on a gradient in the event of a residual creep speed.

5.2.2. Secondary braking system

5.2.2.1. With regard to the secondary braking system the relevant requirements of point 2.1.2.2 of Annex I shall be fulfilled.

5.2.3. Parking braking system

With regard to the parking braking system the requirements of point 2.1.2.3 of Annex I shall be fulfilled.

5.2.3.1. If, in the case of a hydrostatic drive, the vehicle cannot be stopped on a gradient, then it is permissible to operate the parking braking system to stop the vehicle from residual creep speed to standstill. For this purpose the parking braking system has to be designed such that it is possible for it to be actuated during driving.

5.3. Characteristics of the braking systems

5.3.1. The set of braking systems with which a vehicle is equipped shall satisfy the requirements laid down for service, secondary and parking braking systems.

5.3.2. In the event of breakage of any component other than the brakes or the components referred to in point 2.2.1.2.7 of Annex I, or of any other failure of the service braking system the secondary braking system or that part of the service braking system which is not affected by the failure, shall be able to bring the vehicle to a halt in the conditions prescribed for secondary braking, in particular, when the secondary braking system and the service braking system have a common control device and a common transmission; for example, when the braking effect is dependent on the operation of the proper operation of the power transmission i.e. converter, hydraulic pumps, pressure pipes, hydraulic motors or comparable components.

5.3.3. The systems providing service, secondary and parking braking may have common components as long as they fulfil the conditions as specified in point 2.2.1.2 of Annex I.

5.3.4. The braking force distribution of the service brake system shall be designed in such a way that during braking there is no significant moment around the vertical axis of the vehicle if the limit of adhesion between tyres and road on homogeneous road surfaces is not attained.

5.3.5. The braking force distribution of the service braking system shall be by design such that during braking with the service brake system on surfaces with different coefficients of friction of split-μ 0,2/0,8 a minimum deceleration can be achieved that is at least 55 % of the mean fully deceleration dm of the service braking system prescribed for the respective vehicle class (see point 6.3). This can be proven by calculations; in this case the rolling resistance shall not be taken into consideration.

5.3.6. By way of derogation from point 5.3.2, in the event of a failure in the pump control device of the hydrostatic drive, it shall be possible to stop the vehicle with the performance prescribed for the secondary braking system. However, under this failure condition an additional device may be actuated that can always be easily operated from the driving position (for example a device acting on the engine speed, including the engine shut off control).

5.3.7. In the case of an inch device, or other comparable device, which can be operated during driving, provisions shall be taken to ensure that all prescribed requirements of this Annex (especially the braking performance) are still complied with when this type of device is actuated.

5.3.8. Warning signals and warning devices

The relevant requirements of point 2.2.1.29 and point 2.2.1.12 of Annex I shall be fulfilled.

5.3.9. The energy storage devices (energy reservoirs) of power-driven vehicles shall be such that after eight full-stroke actuations of the service braking system control device the pressure remaining in the energy storage device(s) shall be not less than the pressure required to obtain the specified secondary braking performance.

5.3.10. The pneumatic/hydraulic auxiliary equipment shall be supplied with energy in such a way that during its operation, the prescribed deceleration values can be reached and that even in the event of damage to the source of energy the operation of the auxiliary equipment cannot cause the reserves of energy feeding the braking systems to fall below the level indicated in point 2.2.1.12 of Annex I.

5.3.11. Wear of the brakes

The relevant requirements of point 2.2.1.10 of Annex I shall be fulfilled.

5.3.12. In the case of a tractor equipped with a complex electronic vehicle control systems according to Annex X, the requirements of that Annex shall be applied and the operation of the system shall not be adversely affected by magnetic or electrical fields. This shall be demonstrated by compliance with the technical requirements laid down in accordance with the relevant provisions of Article 19 of Delegated Regulation (EU) 2015/208.

5.3.13. If a tractor with a hydrostatic drive is authorised to tow a category R2, R3, R4 or S2 vehicle shall satisfy the relevant requirements of point 2.1.4, 2.1.5, 2.2.1.16, 2.2.1.17 and 2.2.1.18 of Annex I.

5.3.14. Response time

Where a tractor is fitted with a service braking system which is totally or partially dependent on a source of energy other than the muscular effort of the driver, the requirements of point 3.3 of Annex II shall be satisfied for the non-hydrostatic part of the service braking system.

6. Braking tests

6.1. General

6.1.1. The relevant requirements of point 2.1 of Annex II shall be fulfilled.

6.1.2. During the brake test the drivability shall be assessed (e.g. tendency for lifting the rear axle due to the braking action of the service brakes).

6.1.2.1. Lift-off is not permitted for Class III vehicles.

6.1.2.2. Lift-off of an axle is permissible for vehicles of Class I and Class II at a deceleration exceeding 4,5 m/s². However, the driving stability shall be preserved.

Here, the braking effect of the hydrostatic drive has also to be taken into account.

6.2. Type-0 test

6.2.1. General

6.2.1.1. The brake shall be cold. A brake is deemed to be cold when the conditions as specified in point 2.2.1.1 of Annex II are met.

6.2.1.2. The test shall be conducted under the conditions as specified in point 2.2.1.3 of Annex II.

6.2.1.3. The road shall be level.

6.2.2. In the case of manually operated drive control device (Class I and Class II vehicles), the performance of the service brake shall be assessed by moving the drive lever to neutral just before operating the service brake in order to ensure not to brake against the hydrostatic system. In the case of Class III vehicles this sequence shall be automatic, using only the service brake control device.

6.2.3. Service braking system

The limits prescribed for minimum performance, both for tests with the vehicle unladen and for tests with the vehicle laden, are those laid down in point 6.3 for each class of vehicle.

The service braking system has to meet the requirements in point 6.3.1.

When used as a service braking system,

6.2.3.1. a combination hydrostatic braking system shall also meet the requirements with regard to the minimum braking portion of friction brake(s) as specified in point 6.3.1.

6.2.3.2. a combination friction braking system shall also meet the requirements with regard to the minimum braking portion of friction brake(s) as specified in point 6.3.1.

The performance of the friction brake shall also be determined. In this type of test, the effect of the hydrostatic transmission shall be neutralised to assess the friction brake and rolling resistance.

If the hydrostatic brake cannot be disconnected for technical reasons, the proportion of the friction brake may be determined by another method, e.g.:

6.2.3.3. Successive brake tests are performed

6.2.3.3.1 with the combination hydrostatic braking system with the friction brake(s) connected

6.2.3.3.2 with the combination hydrostatic braking system with the friction brake(s) rendered inoperative (only 'hydrostatic braking')

Then this formula is used:

zF = zHy+F – zHy + R


zF	:	Mean fully developed deceleration of the friction braking system including rolling resistance

---	---	---
zHy	:	Mean fully developed deceleration related only to the braking effect of the hydrostatic braking system including rolling resistance

---	---	---
zHy+F	:	Mean fully developed deceleration of the combination hydrostatic braking system.

---	---	---
R	:	Rolling resistance = 0,02

6.2.4. Secondary braking system

6.2.4.1. The secondary braking effectiveness test shall be conducted by either simulating the actual failure conditions in the service braking system or by carrying out this test with a secondary braking system which is independent from the service braking system.

6.2.4.2. The system shall be tested with the appropriate control device.

The prescribed performance shall be obtained by applying to the control device a force not exceeding 600 N on a foot or 400 N on a hand operated control device. The control device shall be so placed that it can be easily and quickly applied by the driver.

6.2.4.3. The limits prescribed for minimum performance, both for tests with the vehicle unladen and for tests with the vehicle laden, are those laid down in point 6.3.2 for each class of vehicle.

6.3. Performance tests of service and secondary braking system (Type-0)

	Laden & Unladen		Class I	Class II	Class III
	(v in km/h; s in m; dm in m/s²)	v	≤ 12	≤ 30	≤ 40
6.3.1.	Service braking system	s	≤ 0,15v + v²/78	≤ 0,15v + v²/92	≤ 0,15v + v²/130
6.3.1.	Service braking system	dm	≥ 3,0	≥ 3,55	≥ 5,0
6.3.1.1.	Minimum braking portion of friction brake(s) in a combination hydrostatic braking system	s	≤ 0,15v + v²/26	≤ 0,15v + v²/40	≤ 0,15v + v²/40
6.3.1.1.	Minimum braking portion of friction brake(s) in a combination hydrostatic braking system	dm	≥ 1,0	≥ 1,5	≥ 1,5
6.3.1.2.	Minimum braking portion of friction brake(s) within a combination friction braking system	s	≤ 0,15v + v²/52	≤ 0,15v + v²/52	≤ 0,15v + v²/78
6.3.1.2.	Minimum braking portion of friction brake(s) within a combination friction braking system	dm	≥ 2,0	≥ 2,0	≥ 3,0
6.3.2.	Secondary braking system	s	≤ 0,15v + v²/40	≤ 0,15v + v²/40	≤ 0,15v + v²/57
6.3.2.	Secondary braking system	dm	≥ 1,5	≥ 1,5	≥ 2,2

6.4. Brake test Type-I (fade)

6.4.1. The service brakes shall be tested in such a manner that, the vehicle being laden, the energy input to the brakes is 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 per cent down-gradient for a distance of 1,7 km.

6.4.2. Alternately, the test may be carried out on a level road, the tractor being drawn by a tractor; during the test, the force applied to the control device shall be adjusted so as to keep the resistance of the towed vehicle constant (7 per cent of the maximum total stationary axle load of the tested tractor). 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 table below:

Speed [km/h]	Distance [metres]
40	1 700
30	1 950
20	2 500
15	3 100

6.4.3. As an alternative to the procedure with continuous braking described in points 6.4.1 and 6.4.2., the test procedure described in point 2.3.1 of Annex II with repeated braking may also be used.

6.4.4. Hot performance

At the end of the Type-I test the hot performance of the service braking system shall be measured in the same conditions (and in particular at a constant control force no greater than the mean force actually used) as for the Type-0 test (the temperature conditions may be different).

6.4.4.1. The hot braking performance of the service braking system shall not be below the limits given in the table of following point 6.4.4.2.

6.4.4.2. Minimum prescribed hot performance (Type-I test)

Service braking system	Hot performance as % of the prescribed value	Hot performance as % of the value recorded during Type-0 test
Hydrostatic braking system	90	90
Combination hydrostatic braking system	90	80
Combination friction braking system	80	60

Friction braking system	80	60

6.4.5. The type-I Test can be omitted provided that the following two conditions are met:

6.4.5.1. At least 60 % of the total braking forces during the Type-0 test of the service braking system (see point 6.2.3) is produced by the braking with the hydrostatic drive.

6.4.5.2. The manufacturer can prove that overheating of the brakes in case of permanent operation is prevented.

6.5. Parking braking system

6.5.1. With regard to the parking braking system the requirements of point 3.1.3 of Annex II shall be fulfilled.

6.5.2. To check compliance with the requirement specified in point 2.2.1.2.4 of Annex I, a Type-0 test shall be carried out with the laden vehicle at an initial test speed of v ≥ 0,8 vmax. The mean fully developed deceleration on application of the control device of the parking braking system and the deceleration immediately before the vehicle stops shall not be less than 1,5 m/s². The force exerted on the braking control device shall not exceed the specified values.

In the case of a manually operated drive control (Class I and Class II vehicles), the performance of the parking brake system in motion shall be assessed by moving the drive control to neutral just before operating the parking braking system in order to ensure not to brake against the hydrostatic system. In the case of Class III vehicles this sequence shall be automatic, using only the parking brake control device.

ANNEX X

Requirements applying to the safety aspects of complex electronic vehicle control systems

1. General

This Annex lays down the requirements for type-approval testing, fault strategy and verification with respect to the safety aspects of complex electronic vehicle control systems related to the braking of agricultural and forestry vehicles.

2. Requirements

All complex electronic vehicle control systems shall comply with the provisions of Annex 18 to UNECE Regulation No 13, as referenced in the following table:

UNECE Regulation No	Subject	Series of amendments	OJ Reference
13	Approval of vehicles of categories M, N and O with regard to braking	Supplement 5 to the 10 series of amendments 11 series of amendments	L 257, 30.9.2010, p. 1 L 297, 13.11.2010, p. 183

ANNEX XI

Requirements and test procedures applying to anti-lock braking systems and to vehicles fitted with them

1. Definitions

For the purposes of this Annex:

1.1. ‘integrated endurance braking system’ means an endurance braking system whose control device is integrated with that of the service braking system in such a way that both endurance and service braking systems are applied simultaneously or suitably phased by operation of the combined control device;

1.2. ‘sensor’ means a component designed to identify and transmit to the controller the conditions of rotation of the wheel(s) or the dynamic conditions of the vehicle;

1.3. ‘controller’ means a component designed to evaluate the data transmitted by the sensor(s) and to transmit a signal to the modulator;

1.4. ‘modulator’ means a component designed to vary the braking force(s) in accordance with the signal received from the controller;

1.5. ‘indirectly controlled wheel’ means a wheel whose braking force is modulated according to data provided by the sensor(s) of other wheel(s);

1.6. ‘full cycling’ means that the anti-lock braking system is repeatedly modulating the brake force to prevent the directly controlled wheels from locking and excluding brake applications where modulation only occurs once during the stop;

1.7. ‘full force’ means the maximum force laid down in the braking tests and performance of braking systems according to this Regulation.

For the purposes of directly and indirectly controlled wheels, anti-lock braking systems with ‘select-high’ control are deemed to include both directly and indirectly controlled wheels; in systems with ‘select-low’ control, all sensed wheels are deemed to be directly controlled wheels.

2. General

2.1. This Annex lays down the required braking performance for agricultural vehicles fitted with anti-lock braking systems.

The maximum design speed for which such requirements are provided is meant, throughout this Annex, to be in the forward direction of the vehicle travel, unless otherwise explicitly mentioned.

2.2. The anti-lock braking systems known at present comprise a sensor or sensors, a controller or controllers and a modulator or modulators. Any device of a different design which may be introduced in the future, or where an anti-lock braking function is integrated into another system, shall be deemed to be anti-lock braking systems within the meaning of this Annex if they provide performances equal to those prescribed by this Annex.

2.3. Deviations from the prescribed test procedures are permitted in case that testing conditions cannot be complied with due to a too low maximum design speed of the tractor. In such a case the equivalence of the prescribed performances has to be demonstrated with the method of assessment and results being appended to the type approval report.

3. Types of anti-lock braking systems

3.1. A tractor is deemed to be equipped with an anti-lock braking system if one of the following systems is fitted:

3.1.1. Category 1 anti-lock braking system: A vehicle equipped with a category 1 anti-lock braking system shall meet all the relevant requirements of this Annex.

3.1.2. Category 2 anti-lock braking system: A vehicle equipped with a category 2 anti-lock braking system shall meet all the relevant requirements of this Annex, except those of point 5.3.5.

3.1.3. Category 3 anti-lock braking system: A vehicle equipped with a category 3 anti-lock braking system shall meet all the relevant requirements of this Annex except those of points 5.3.4 and 5.3.5 On such vehicles, any individual axle (or bogie) which does not include at least one directly controlled wheel shall fulfil the conditions of adhesion utilisation and the wheel-locking sequence of Appendix 1 to Annex II, with regard to the braking rate and the load respectively. Those requirements may be checked on high- and low-adhesion coefficient road surfaces (about 0,8 and 0,3 maximum) by modulating the service braking control force.

3.2. A towed vehicle shall be deemed to be equipped with an anti-lock braking system when at least two wheels on opposite sides of the vehicle are directly controlled and all remaining wheels are either directly or indirectly controlled by the anti-lock braking system. In the case of drawbar towed vehicles, at least two wheels on one front axle and two wheels on one rear axle shall be directly controlled with each of these axles having at least one independent modulator and all remaining wheels are either directly or indirectly controlled. In addition, the anti-lock equipped towed vehicle shall meet one of the following conditions:

3.2.1. Category A anti-lock braking system: A towed vehicle equipped with a category A anti-lock braking system shall meet all the relevant requirements of this Annex.

3.2.2. Category B anti-lock braking system: A towed vehicle equipped with a category B anti-lock braking system shall meet all the relevant requirements of this Annex, except point 6.3.2.

4. General requirements

4.1. Failures within the electric control transmission of the anti-lock braking system that affects the system with respect to the functional and performance requirements in this Annex, shall be signalled to the driver by a specific optical warning signal. The yellow warning signal specified in point 2.2.1.29.1.2 of Annex I shall be used for this purpose.

Until uniform test procedures have been agreed, the manufacturer shall provide the Technical Service with an analysis of potential failures within the control transmission and their effects. That information shall be subject to discussion and agreement between the Technical Service and the vehicle manufacturer.

4.1.1. Sensor anomalies, which cannot be detected under static conditions, shall be detected not later than when the vehicle speed exceeds 10 km/h. However, to prevent erroneous fault indication when a sensor is not generating a speed output, due to non-rotation of a wheel, verification may be delayed but detected not later than when the vehicle speed exceeds 15 km/h. The warning signal may light up again while the vehicle is stationary, provided that it is extinguished before the vehicle speed reaches 10 km/h or 15 km/h, as appropriate, when no defect is present.

4.1.2. When the anti-lock braking system is energised with the vehicle stationary, electrically controlled pneumatic modulator valve(s) shall cycle at least once.

4.2. Tractors equipped with an anti-lock braking system and authorised to tow a towed vehicle equipped with such a system shall be fitted with a separate optical warning signal for the anti-lock braking system of the towed vehicle, meeting the requirements of point 4.1. The separate warning signals specified in point 2.2.1.29.2 of Annex I shall be used for this purpose, activated via pin 5 of the electrical connector conforming to ISO 7638:2003. The ISO 7638:2003 connector may be used for 5 pin or 7 pin applications, as appropriate.

4.2.1. The warning signal shall not light up when a towed vehicle without an anti-lock braking system is coupled or when no towed vehicle is coupled. This function shall be automatic.

4.3. In the event of a failure as described in point 4.1, the following requirements shall apply:

Tractors: The residual braking performance in the event of a failure of part of the transmission of the service braking system shall be 1,3 m/s². That requirement shall not be construed as a departure from the requirements concerning secondary braking.

Towed vehicles: The residual braking performance shall be of at least 30 per cent of the prescribed performance for the service braking system of the relevant towed vehicle.

4.4. The operation of the system shall not be adversely affected by magnetic or electrical fields. That requirement shall be demonstrated by compliance with the technical requirements laid down in Article 19 of Delegated Regulation (EU) 2015/208.

4.5. A manual device shall not be provided to disconnect or change the control mode of the anti-lock braking system, except on tractors of category T or C. Where a device is fitted to tractors of category T or C, the following conditions shall be met:

4.5.1. An optical warning signal shall inform the driver that the anti-lock braking system has been disconnected or the control mode changed; the anti-lock failure warning signal specified in point 2.2.1.29.1.2 of Annex I may be used for this purpose. The warning signal shall be constant or flashing.

4.5.2. The anti-lock braking system shall automatically be reconnected/returned to on-road mode when the ignition (start) device is again set to the 'on' (run) position or the vehicle speed exceeds 30 km/h.

4.5.3. The vehicle user's handbook provided by the manufacturer should warn the driver of the consequences of manual disconnection or mode change of the anti-lock braking system.

4.5.4. The device referred to in point 4.5 may, in conjunction with the tractor, disconnect/change the control mode of the anti-lock braking system of the towed vehicle. A separate device for the towed vehicle alone is not permitted.

4.5.5. Devices changing the control mode of the anti-lock braking system are not subject to point 4.5 if in the changed control mode condition all requirements for the category of anti-lock braking system with which the vehicle is equipped are fulfilled. However, in such a case, points 4.5.1, 4.5.2, and 4.5.3 shall be met.

4.6. In the case of vehicles which are equipped with an anti-lock braking system and with an integrated endurance braking system, the anti-lock braking system shall act at least on the service brakes of the endurance braking system's controlled axle and on the endurance braking system itself, and shall fulfil the relevant requirements of this Annex.

4.7. In the case of towed vehicles with pneumatic braking systems, full cycling of the anti-lock braking system is only assured when the pressure available at any brake actuator of a directly controlled wheel is more than 100 kPa above the maximum cycling pressure throughout a given test. The supply pressure available may not be increased above 800 kPa.

In the case of towed vehicles with hydraulic braking systems, full cycling of the anti-lock braking system is only assured when the pressure available at any brake actuator of a directly controlled wheel is more than 1 750 kPa above the maximum cycling pressure throughout a given test. The available energy level provided to the anti-lock braking system may not be increased above 14 200 kPa.

5. Special provisions concerning tractors

5.1. Energy consumption

Tractors equipped with anti-lock braking systems shall maintain their performance when the service braking control device is fully applied for long periods. Compliance with the requirement shall be verified by means of the procedure referred to in points 5.1.1, 5.2.3, 5.2.4, 5.2.5, 5.3, 6.1.1, 6.1.3, 6.1.4, 6.3:

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 energy storage device(s) for pneumatic auxiliary equipment shall be isolated.

5.1.1.2. From an initial speed of not less than 50 km/h (or vmax, whichever is lower), on a surface with a coefficient of adhesion of 0,3 or less, the brakes of the laden vehicle shall be fully applied for a time t, during which time the energy consumed by the indirectly controlled wheels shall be taken into consideration and all directly controlled wheels shall remain under control of the anti-lock braking system throughout that time.

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 service. The actual value obtained and the type of tyres and surface shall be recorded.

5.1.1.3. The vehicle's engine shall be then stopped or the supply to the energy storage device(s) cut off.

5.1.1.4. The service braking control device shall be then fully actuated four times in succession with the vehicle stationary.

5.1.1.5. When the control device is applied for the fifth time, it shall 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 vehicle authorised to tow a vehicle equipped with a compressed-air braking system, the supply line shall be blocked off and an energy storage device of 0,5 litre capacity shall be connected to the control line (in accordance with point 1.2.2.3 of Annex IV, section A). When the brakes are applied for the fifth time, as provided in point 5.1.1.5 of this Annex, the energy level supplied to the control line shall 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 is measured with the vehicle in question, by the method described in point 1.1 of Appendix 2.

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 15 seconds.

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. From the second phase, the energy consumption corresponding to the initial brake application may be taken into account, by subtracting one full brake application from the four full applications prescribed in points 5.1.1.4, 5.1.1.5, 5.1.1.6 and 5.1.2.6 for each of the second, third and fourth phases used in the test procedure prescribed in point 5.1.1 as applicable.

5.1.2.6. The performance prescribed in point 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. Utilisation of adhesion

5.2.1. The utilisation of adhesion by the anti-lock braking system takes into account the actual increase in braking distance beyond the theoretical minimum. The anti-lock braking system shall be deemed to be satisfactory when the condition

ε ≥ 0,75

is satisfied, where ε represents the adhesion utilised, as described in point 1.2 of Appendix 2.

5.2.2. The adhesion utilisation (ε) shall be measured on road surfaces with a coefficient of adhesion of 0,3 or less, and of about 0,8 (dry road), with an initial speed of 50 km/h or vmax, whichever is the lower. To eliminate the effects of differential brake temperatures it is recommended that zAL (see Appendix 1) be determined prior to the determination of k.

5.2.3. The test procedure to determine the coefficient of adhesion (k) and the formulae for calculation of the adhesion utilisation (ε) shall be those laid down in Appendix 2.

5.2.4. The utilisation of adhesion by the anti-lock braking system shall be checked on complete vehicles equipped with anti-lock braking systems of categories 1 or 2. In the case of vehicles equipped with category 3 anti-lock braking systems, only the axle(s) with at least one directly controlled wheel shall satisfy this requirement.

5.2.5. The condition ε ≥ 0,75 shall be checked with the vehicle laden and unladen. The laden test on the high-adhesion surface may be omitted if the prescribed force on the control device does not achieve full cycling of the anti-lock braking system. For the unladen test, the control force may be increased up to 1 000 N if no cycling is achieved with its full force value. A higher force value than the one of the full force may be used if required to activate the anti-lock braking system. If 1 000 N is insufficient to make the system cycle, then this test may be omitted. For air braking systems, the air pressure may not be increased above the cut-out pressure for the purpose of this test.

5.3. Additional checks

The following additional checks shall be carried out with the engine disconnected, with the vehicle laden and unladen:

5.3.1. The wheels directly controlled by an anti-lock braking system shall not lock when the full force is suddenly applied on the control device, on the road surfaces specified in point 5.2.2, at an initial speed of 40 km/h and at a high initial speed as indicated in the table below: Condition Maximum test speed High adhesion surface 0,8 vmax ≤ 80 km/h Low adhesion surface 0,8 vmax ≤ 70 km/h

5.3.2. When an axle passes from a high-adhesion surface (kH) to low-adhesion surface (kL) where kH ≥ 0,5 and kH/kL ≥ 2, with the full force applied on the control device, the directly controlled wheels shall not lock. The running speed and the instant of applying the brakes shall be so calculated that, with the anti-lock braking system 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 point 5.3.1 above.

5.3.3. When a vehicle passes from a low-adhesion surface (kL) to a high-adhesion surface (kH) where kH ≥ 0,5 and kH/kL ≥ 2, with the full force applied on the control device, the deceleration of the vehicle shall rise to the appropriate high value within a reasonable time and the vehicle shall not deviate from its initial course. The running speed and the instant of applying the brakes shall be so calculated that, with the anti-lock braking system fully cycling on the low-adhesion surface, the passage from one surface to the other occurs at approximately 50 km/h or 0,8 vmax, whichever is the lower.

5.3.4. In the case of vehicles equipped with anti-lock braking systems of categories 1 and 2, when the right and left wheels of the vehicle are situated on surfaces with differing coefficients of adhesion (kH and kL) where kH ≥ 0,5 and kH/kL ≥ 2 the directly controlled wheels shall not lock when the full force is suddenly applied on the control device at a speed of 50 km/h or 0,8 vmax, whichever is the lower.

5.3.5. Furthermore, laden vehicles equipped with anti-lock braking systems of category 1 shall, under the conditions of point 5.3.4, satisfy the braking rate prescribed in Appendix 3.

5.3.6. However, in the tests provided for in points 5.3.1, 5.3.2, 5.3.3, 5.3.4 and 5.3.5, brief periods of wheel-locking are allowed. Furthermore, wheel-locking is permitted 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 shall not be affected.

5.3.7. During the tests provided for in points 5.3.4 and 5.3.5, steering correction is permitted if the angular rotation of the steering control device is within 120° during the initial 2 seconds and not more than 240° in all. Furthermore, at the beginning of these tests the longitudinal median plane of the vehicle shall pass over the boundary between the high- and low-adhesion surfaces and during these tests no part of the (outer) tyres shall cross this boundary.

5.3.8. The following notes are taken into account:
5.3.8.1. kH and kL are measured as laid down in Appendix 2 to this Annex.
5.3.8.2. The purpose of the tests in the following points 5.3.1, 5.3.2, 5.3.3 and 5.3.4 is to check that the directly controlled wheels do not lock and that the vehicle remains stable. In these tests a higher force value than the one of the full force may be used if required to activate the anti-lock braking system.
5.3.8.3. With regard to points 5.3.1 and 5.3.2 it is not necessary, therefore, to make complete stops and bring the vehicle to a complete halt on the low-adhesion surface.

6. Special provisions concerning towed vehicles

6.1. Energy consumption

Towed vehicles equipped with anti-lock braking systems shall be so designed that, even after the service braking control device 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 adhesion, and with the brakes adjusted as closely as possible and with the brake load sensing device (if fitted) held in the 'laden' position throughout the test.

If the coefficient of adhesion of the test track is too high, preventing the anti-lock braking system from cycling then the test may be carried out on a surface with a lower coefficient of adhesion.

6.1.2. In the case of compressed-air braking systems, the initial energy level in the energy storage device(s) shall be equivalent to a pressure of 800 kPa at the coupling head of the towed vehicle's supply line.

6.1.3. With an initial vehicle speed of at least 30 km/h, the brakes shall be fully applied for a time t = 15 s, during which time the energy consumed by the indirectly controlled wheels shall be taken into consideration and all directly controlled wheels shall remain under control of the anti-lock braking system. During this test, the supply to the energy storage device(s) shall be cut off. If the time t = 15 s cannot be completed in a single braking phase, further phases may be used. During these phases, no fresh energy shall be supplied to the energy storage device(s) and, as from the second phase, the additional energy consumption for filling the actuators is to be taken into account, e.g. by the following test procedure. The pressure in the reservoir(s) when starting the first phase is to be that stated in point 6.1.2. At the beginning of the following phase(s), the pressure in the reservoir(s) after application of the brakes shall be not less than the pressure in the reservoir(s) at the end of the preceding phase. At the subsequent phase(s), the only time to be taken into account is from the point at which the pressure in the reservoir(s) is equal to that at the end of the preceding phase.

6.1.4. At the end of the braking, with the vehicle stationary, the service braking control device shall be fully actuated four times. During the fifth application, the pressure in the operating circuits shall be sufficient to provide a total braking force at the periphery of the wheels equal to not less than 22,5 % of the maximum stationary wheel load and without causing an automatic application of any braking system not being under the control of the anti-lock braking system.

6.2. Utilisation of adhesion

6.2.1. Towed vehicles equipped with an anti-lock braking system shall be deemed acceptable when the condition ε ≥ 0,75 is satisfied, where ε represents the adhesion utilised, as defined in point 2 of Appendix 2. This condition shall be verified with the vehicle unladen, on a straight and level road with a surface having a good coefficient of adhesion.

If the coefficient of adhesion of the test track is too high, preventing the anti-lock braking system from cycling then the test may be carried out on a surface with a lower coefficient of adhesion.

In the case of trailers fitted with a brake load sensing device the pressure setting may be increased to ensure full cycling.

6.2.2. To eliminate the effects of differential brake temperatures, it is recommended that zRAL be determined prior to the determination of kR.

6.3. Additional checks

6.3.1. At speeds exceeding 15 km/h, the wheels directly controlled by an anti-lock braking system shall not lock when the full force is suddenly applied on the control device of the tractor. This shall be checked, under the conditions prescribed in point 6.2, at initial speeds of 40 km/h and 60 km/h.

6.3.2. The provisions of this point shall only apply to towed vehicles equipped with an anti-lock braking system of category A. When the right and left wheels are situated on surfaces which produce differing maximum braking rates (zRALH and zRALL), where

Symbol	Notes
E	wheelbase
ER	distance between coupling point and centre of axle(s) of rigid drawbar towed vehicle (or distance between coupling point and centre of axle(s) of centre-axle towed vehicle)
ε	the adhesion utilised by the vehicle: quotient of the maximum braking rate with the anti-lock braking system operative (zAL) and the coefficient of adhesion (k)
εi	the ε-value measured on axle i (in the case of a tractor with a category 3 anti-lock braking system)
εΗ	the ε-value on the high-friction surface
εL	the ε-value on the low-friction surface
F	force [N]
FbR	braking force of the towed vehicle with the anti-lock braking system inoperative
FbRmax	maximum value of FbR
FbRmaxi	value of FbRmax with only axle i of the towed vehicle braked
FbRAL	braking force of the towed vehicle with the anti-lock braking system operative
FCnd	total normal reaction of road surface on the un-braked and non-driven axles of the vehicle combination under static conditions
FCd	total normal reaction of road surface on the un-braked and driven axles of the vehicle combination under static conditions
Fdyn	normal reaction of road under dynamic conditions with the anti-lock braking system operative
Fidyn	Fdyn on axle i in case of tractors or drawbar towed vehicle
Fi	normal reaction of road surface on axle i under static conditions
FM	total normal static reaction of road surface on all wheels of the tractor
FMnd [^E0006]	total normal static reaction of road surface on the un-braked and non-driven axles of the tractor
FMd	total normal static reaction of road surface on the un-braked and driven axles of the power-driven vehicle
FR	total normal static reaction of road surface on all wheels of towed vehicle
FRdyn	total normal dynamic reaction of road surface on the axle(s) of rigid drawbar towed vehicle or centre-axle towed vehicle
FwM	0,01 FMnd + 0,015 FMd
g	acceleration due to gravity (9,81 m/s²)
h	height of centre of gravity specified by the manufacturer and agreed by the technical service conducting the approval test
hD	height of drawbar (hinge point on towed vehicle)
hK	height of fifth wheel coupling (king pin)
hR	height of centre of gravity of the towed vehicle
k	coefficient of adhesion between tyre and road
kf	k-factor of one front axle
kH	k-value determined on the high-friction surface
ki	k-value determined on axle i for a vehicle with a category 3 anti-lock braking system
kL	k-value determined on the low-friction surface
klock	value of adhesion for 100 % slip
kM	k-factor of the tractor
kpeak	maximum value of the curve ‘adhesion versus slip’
kr	k-factor of one rear axle
kR	k-factor of the towed vehicle
P	mass of individual vehicle [kg]
R	ratio of kpeak to klock
t	time interval [s]
tm	mean value of t
tmin	minimum value of t
z	braking rate [m/s²]
zAL	braking rate z of the vehicle with the anti-lock braking system operative
zC	braking rate z of the vehicle combination, with the towed vehicle only braked and the anti-lock braking system inoperative
zCAL	braking rate z of the vehicle combination, with the towed vehicle only braked and the anti-lock braking system operative
zCmax	maximum value of zC
zCmaxi	maximum value of zC, with only axle i of the towed vehicle braked
zm	mean braking rate
zmax	maximum value of z
zMALS	zAL of the tractor on a ‘split surface’
zR	braking rate z of the towed vehicle with the anti-lock braking system inoperative
zRAL	zAL of the towed vehicle obtained by braking all the axles, the tractor un-braked and its engine disconnected
zRALH	zRAL on the surface with the high coefficient of adhesion
zRALL	zRAL on the surface with the low coefficient of adhesion
zRALS	zRAL on the split surface
zRH	zR on the surface with the high coefficient of adhesion
zRL	zR on the surface with the low coefficient of adhesion
zRHmax	maximum value of zRH
zRLmax	maximum value of zRL
zRmax	maximum value of zR

Commission Delegated Regulation (EU) 2015/68 of 15 October 2014 supplementing Regulation (EU) No 167/2013 of the European Parliament and of the Council with regard to vehicle braking requirements for the approval of agricultural and forestry vehicles Text with EEA relevance

5.2.2. Secondary braking system

5.2.3. Parking braking system

5.3. Characteristics of the braking systems

6. Braking tests

6.1. General

6.2. Type-0 test

6.2.1. General

6.3. Performance tests of service and secondary braking system (Type-0)

6.4. Brake test Type-I (fade)

6.5. Parking braking system

ANNEX X

Requirements applying to the safety aspects of complex electronic vehicle control systems

1. General

2. Requirements

ANNEX XI

Requirements and test procedures applying to anti-lock braking systems and to vehicles fitted with them

1. Definitions

2. General

3. Types of anti-lock braking systems

4. General requirements

5. Special provisions concerning tractors

5.1. Energy consumption

5.1.1. Test procedure

5.1.2. Additional requirements

5.2. Utilisation of adhesion

5.3. Additional checks

6. Special provisions concerning towed vehicles

6.1. Energy consumption

6.2. Utilisation of adhesion

6.3. Additional checks

Appendix 1

Symbols

Appendix 2

Utilisation of adhesion

1. Method of measurement for tractors

1.1. Determination of the coefficient of adhesion (k)

1.2. Determination of the adhesion utilised (ε)

2. Method of measurement for towed vehicles

2.1. General

2.2. Drawbar towed vehicles

2.3. Rigid drawbar towed vehicles and centre-axle towed vehicles

Appendix 3

Performance on differing adhesion surfaces

1. Tractors

2. Towed vehicles

Appendix 4

Method of selection of the low-adhesion surface

ANNEX XII

Requirements applying to EBS of vehicles with compressed-air braking systems or of vehicles with data communication via pin 6 and 7 of ISO 7638 connector and to vehicles fitted with such EBS

1. Definitions

2. General requirements

3. Special requirements for the connections between tractors and towed vehicles for compressed-air braking systems

4. Special additional requirements for service braking systems with electric control transmission

4.1. Tractors