Document ID: chunk:federal_register_of_legislation:F2006L03061:body:0:p20
Version: federal_register_of_legislation:F2006L03061
Segment Type: other
Provision Reference: 
Character Range: 55105–58212

radius of the tyre fitted to the wheel.

In most cases this will be the same as for the 'Foundation Brakes'.

38.4.3.1.1.              Where the actuating force is dependent on the stroke, as in the case of spring brakes, the force used in the equation above shall be that corresponding to the stroke determined from the data provided for the 'Brake Device' at the required actuating force. In the case of spring brakes the actuating force may be converted to an equivalent air pressure and actuator area so the units of the calculation are compatible.

38.4.3.2.                    The ratio of brake force to static 'Axle Load' at each 'Axle' must not exceed that specified in the data for the suspension as 'Approved' under the provision of clause 38.4.6.3. Higher values correspond to wheel skid and unrealised braking potential.

38.4.4.                          Parking Brake Calculation

38.4.4.1.                    The performance of the 'Parking Brake System 38/00' shall be determined on the basis of the characteristics of the 'Foundation Brakes' (where applicable) provided under clause 38.4.6.2 ('Foundation Brakes') and the control force available at the 'Brakes' actuator.

38.4.4.2.                    The provisions of clause 38.4.3.1.1 (spring brake force) shall apply.

38.4.4.3.                    When 'Emergency Brake System' performance data are used to demonstrate compliance of the 'Parking Brake System 38/00', the geometry of the 'Brakes' shall be such that brake effectiveness will be not less in the reverse direction.

38.4.5.                          Time Response

38.4.5.1.                    The time response of a 'Brake System' may be taken as complying with the requirements of this Rule if the 'Brake System' is installed in a manner identical to that prescribed in the documentation describing the 'Approved' 'Control System' used, except as allowed in clause 38.4.5.2.

38.4.5.2.                    Actuator sizes and line lengths may be reduced to less than those specified in the 'Approved' 'Control System' documentation, but devices, fittings and other dimensions may not be changed without voiding approval of the 'Control System' in regard to time response.

38.4.6.                          Specification of 'Brake System' Components

Sub-assemblies of 'Brake System' components may be 'Approved' by the 'Administrator' as part of the 'Brake System' approval process where information has been supplied in accordance with the requirements of this clause.

38.4.6.1.                    'Control System'

38.4.6.1.1.              The 'Control System' shall be characterised by comparing output and input signal strengths at not less than five points equally spaced over the range 0.2 'E' to 1.0 'E'.

38.4.6.1.2.              The input signal strength shall be the final value of the signal and shall be applied to the 'Control System' such that it rises from zero to 65 percent of the final value in not more than 0.22 second. In the case of air 'Brake System's' the input 'Control Signal' strength (kPa) will be measured at the trailer 'Control