Document ID: chunk:federal_register_of_legislation:F2006L03061:body:0:p17
Version: federal_register_of_legislation:F2006L03061
Segment Type: other
Provision Reference: 
Character Range: 47045–49986

the control of an 'Antilock System'.

38.3.11.                      Time Response Measurement

38.3.11.1.                Except where hydraulic brakes are used, each 'Unique' trailer 'Brake System' shall be shown to meet the requirements of clause 38.2.2.3 (actuation time) and clause 38.2.2.4 (release time) by testing in accordance with clause 38.3.11.3 or on the basis of a calculation in accordance with clause 38.4.5 (time response calculation).

38.3.11.2.                A variant of a 'Unique' trailer 'Brake System' will be considered to be identical in regard to time response, when the only variation from the 'Unique' 'Brake System' is one or more of the following:

            (a)  Plumbing or energy transmission line lengths and number of fittings are reduced but other characteristics including diameter, material, type of connecting fittings and the characteristic transmission loss per unit length are not changed.

            (b)  Entire subsections of the 'Brake System' have been removed, as would be the case in converting a modular three 'Axle' system to a modular two 'Axle' system, such that the effect if any is to slightly increase the energy flow rate to and from the remaining brake sub-systems.

            (c)  The energy required to actuate the substitute brake actuators to their maximum design level is less.

38.3.11.3.                Where a trailer 'Brake System' is required to be tested for compliance with clause 38.2.2.3 and clause 38.2.2.4 in the case of compressed air 'Brake System', the test rig described in Figure 2 shall be calibrated in accordance with clause 38.3.11.3.2 and connected as described in Figure 3.

38.3.11.3.1.          Where a rear service coupling for towed trailers is provided, time responses shall be measured with an 800 millilitres vessel attached to the rear service coupling as in Figure 3.

38.3.11.3.2.          The test rig described in Figure 2 shall be calibrated by adjustment of the orifice (O) such that with the storage reservoir (R1) charged to 1.0 'E' (650 kPa), the time between the initial pressure drop measured between the storage reservoir and the control valve (V), and the pressure at the end of the calibrating vessel (R2) increasing to 0.65 'E' (420 kPa), is between 0.18 and 0.22 seconds.

38.3.11.3.3.          The test rig and the trailer energy storage devices shall be charged to 1.0 'E' (650 kPa) prior to the test being conducted and no additional energy shall be added to the storage vessel (R1) or the trailer 'Supply Line' during the period of the test.

38.3.11.3.4.          The brake actuation time shall be taken from when the pressure level, measured between the storage reservoir and the control valve, initially drops to when the pressure in the least favoured brake actuator reaches 0.65 'E' (420 kPa).

38.3.11.3.5.          With an initial service brake application level of 1.0 'E' (650 kPa) the brake release time