BC Transit – Air Brake Course

Identifying Primary and Secondary Systems
The Compressor, Governor, and Supply Reservoir appear in blue. The
safety valve is above the wet tank.
Air from the supply tank, flows into TWO new reservoirs. The GREEN
reservoir will be supplying air to the REAR brakes. The RED reservoir
will be supplying air to the FRONT brakes.
The REAR brakes will be referred to as the PRIMARY brakes.
The FRONT brakes will be referred to as the SECONDARY brakes.
There is a very good reason for making this distinction… next slide...
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