The compatibility between motor vehicles and trailers relates not only to stability, but also to wear optimization. Wear optimization and low adhesion utilization requires good braking balance between axles in the pressure range up to 200 kPa. This improvement in balance is achieved by minimizing the variation in pressure when all brakes start to develop a braking force.
BS ISO 20918:2007 provides a best practice for determining the threshold pressure at which a brake starts to develop a braking force. It is applicable to all vehicles equipped with a conventional braking system and to trailers equipped with an electronic braking system (EBS) when used in conjunction with conventional equipped vehicles, the connector being connected in accordance with ISO 7638. For EBS equipped motor vehicles, it is intended that the default values for the threshold pres combinations with pneumatic braking systems, by means of a roller brake tester.
This international standard describes procedures for workshops and garages and provides
- a recommended pressure range of the system threshold pressure for motor vehicles and trailers
- a recommended practice for determining the system threshold pressure.