Document ID: chunk:federal_register_of_legislation:F2025C00113:reg:4:p6
Version: federal_register_of_legislation:F2025C00113
Segment Type: reg
Provision Reference: reg 4 (pt 6/10)
Character Range: 85956–88988

national standard as a 'Vehicle Stability Function').

APPENDIX 4

 Electrical requirements for all trailers (over 4.5 tonnes 'ATM') incorporating an electric 'Control Line', an 'Antilock System', or a 'Vehicle Stability Function'

 1.                                  Electrical supply system requirements
     1.                            Each trailer must be fitted at the front with a special connector conforming to ISO 7638‑1:2003 configured for 24 volt operation or ISO 7638‑2:2003 configured for 12 volt operation.  The 'Vehicle Stability Function' and the 'Antilock Systems' of the trailer must be able to be simultaneously powered by an electrical supply from a towing vehicle through this connector.
     2.                            Each ISO 7638 connector[2] must be wired to have the following functions:
Contact 1 +ve high current trailer solenoid valve supply;
Contact 2 +ve low current trailer electronic unit supply;
Contact 3 -ve low current trailer electronic unit supply;
Contact 4 -ve high current trailer solenoid valve supply; and
Contact 5 trailer warning signal, switched to -ve (e.g. contact 3 or contact 4) upon fault detection as well as for the signal check required by clause 1.4 below.
 1.                            The continuous current capacity of the electrical conductive material between each contact of an ISO 7638 connector at the front of a trailer and the brake systems (e.g. electronic control unit(s), solenoid valves) which current flows to or from within the trailer, must be at least the following:
           12 volt connector  24 volt connector
Contact 1  20 amps            10 amps
Contact 2  4 amps             2 amps
Contact 3  6 amps             3 amps
Contact 4  20 amps            10 amps
Contact 5  2 amps             1 amp

 1.                            Each trailer equipped with an 'Antilock System', must connect contact 5 of the applicable electrical connector to -ve (e.g. contact 3 or contact 4) for at least 2 seconds once initially energised, and if no fault / defect is present, then disconnect contact 5 from -ve at this time or before the trailer reaches a speed of 15 km/h.

 1.                            Each trailer equipped with a 'Vehicle Stability Function' and/or an 'Antilock System', must connect contact 5 of the applicable electrical connector to -ve (e.g. contact 3 or contact 4) whenever:
            1.             There is a break in the supply of electricity to a 'Vehicle Stability Function' and/or an 'Antilock System' and any electrical failure of a 'Vehicle Stability Function' and/or an 'Antilock System', other than a failure of one or all of the electrical conductors between contacts 3, 4 and 5 on the electrical connector and the vehicle stability/antilock control module; or
            2.             The supply voltage to the trailer falls below a value nominated by the manufacturer at which the prescribed requirements for any of the braking functions required by clause 7.2 of this standard can no longer be met.
            1.