Track test. 1.7.1.1. The adjustment of the brakes shall, prior to the Type-III test below, be set according to the following procedures as appropriate:
1.7.1.1.1. In the case of trailers equipped with air operated brakes the adjustment of the brakes shall be such as to enable the automatic brake adjustment device to function. For this purpose the actuator stroke shall be adjusted to s0 ≥ 1.1 x sre-adjust (the upper limit shall not exceed a value recommended by the manufacturer): Where: sre-adjust is the re-adjustment stroke according to the specification of the manufacturer of the automatic brake adjustment device, i.e. the stroke, where it starts to re-adjust the running clearance of the brake with an actuator pressure of 100 kPa. Where, by agreement with the Technical Service, it is impractical to measure the actuator stroke, the initial setting shall be agreed with the Technical Service. From the above condition the brake shall be operated with an actuator pressure of 200 kPa, 50 times in succession. This shall be followed by a single brake application with an actuator pressure of ≥ 650 kPa.
1.7.1.1.2. In the case of trailers equipped with hydraulically operated disc brakes no setting requirements are deemed necessary.
1.7.1.1.3. In the case of trailers equipped with hydraulically operated drum brakes the adjustment of the brakes shall be as specified by the manufacturer.
1.7.1.2. For the road test the conditions shall be as follows: Number of brake applications 20 Duration of a braking cycle 60 s Initial speed at the beginning of braking 60 km/h Braking applications In these tests, the force applied to the control shall be so adjusted as to attain the mean fully developed deceleration of 3 m/s2 in respect to the trailer mass PR at the first brake application; this force shall remain constant throughout the succeeding brake applications. The braking rate of a trailer is calculated according to the formula given in paragraph 1.4.4.3. of this annex: zR = (z R+M - R) . (PM + PR) + R PR The speed at the end of braking (Annex 11, Appendix 2, paragraph 3.1.5.): PM + P1 + P2 /4 PM + P1 + P2 v2 = v1 .
Track test. 1.7.1.1. The adjustment of the brakes shall, prior to the Type-III test below, be set according to the following procedures as appropriate:
1.7.1.1.1. In the case of trailers equipped with air operated brakes the adjustment of the brakes shall be such as to enable the automatic brake adjustment device to function. For this purpose the actuator stroke shall be adjusted to s0 $ 1.1 " sre-adjust (the upper limit shall not exceed a value recommended by the manufacturer) where: sre-adjust is the re-adjustment stroke according to the specification of the manufacturer of the automatic brake adjustment device, i.e. the stroke, where it starts to re-adjust the running clearance of the brake with an actuator pressure of 1.0 bar. Where, by agreement with the Technical Service, it is impractical to measure the actuator stroke, the initial setting shall be agreed with the Technical Service. From the above condition the brake shall be operated with an actuator pressure of 2.0 bar, 50 times in succession. This shall be followed by a single brake application with an actuator pressure of $ 6.5 bar.
1.7.1.1.2. In the case of trailers equipped with hydraulically operated disc brakes no setting requirements are deemed necessary.
1.7.1.1.3. In the case of trailers equipped with hydraulically operated drum brakes the adjustment of the brakes shall be as specified by the manufacturer.
1.7.1.2. For the road test the conditions shall be as follows: number of brake application: 20. (etc. .... remaining old text of paragraph 1.7.1. unchanged)” Add a new paragraph 1.7.3., to read:
Track test. 4.5.1.1. The brake performance test shall be carried out on a single axle only.
4.5.1.2. The tests shall be carried out on a straight level track, with a surface affording good adhesion, and performed when there is no wind liable to affect the results.
4.5.1.3. The trailer shall be loaded (as closely as possible) to the maximum technically permitted mass for each brake, however, additional mass may be added if required to ensure that sufficient mass is over the axle under test to achieve a braking rate of 0.55 TR/(maximum technically permitted mass per brake) without wheel lock.
4.5.1.4. The dynamic rolling radius of the tyre may be verified at low speed, < 10 km/h, by measuring the distance travelled as a function wheel revolutions, the minimum number of revolutions required to determine the dynamic rolling radius is 10.
4.5.1.5. The rolling resistance of the vehicle combination is to be determined by measuring the time taken for the vehicle speed to reduce from 55 to 45 km/h and the distance covered, when tested in the same direction in which the verification test will be carried out and with the engine disconnected and any endurance brake system disengaged.
4.5.1.6. Only the brakes of the axle under test shall be actuated and reach an input pressure at the brake input device of 90 + 3 per cent (after maximum build up time of 0.7 s) of its asymptotic value. The test shall be carried out with the engine disconnected and any endurance braking system disengaged.
4.5.1.7. The brakes shall be closely adjusted at the start of the test.
4.5.1.8. The brake input for the purpose of calculating the brake threshold torque shall be determined by lifting the wheel and gradually applying the brake whilst the wheel is rotated by hand until resistance is detected.
4.5.1.9. The final speed v2 shall be determined in accordance with annex 11, appendix 2, paragraph 3.1.5.
4.5.1.10. The braking performance of the axle under test shall be determined by calculating the deceleration determined from a direct measurement of velocity and distance between 0.8 v1 and v2, where v2 shall not be less than 0.1 v1. This shall be deemed to be equivalent to the mean fully developed deceleration (MFDD) as defined in annex 4 above.
