BC Transit – Air Brake Course

Secondary Air Loss in a Simple Dual Circuit System
In this example, an air loss will occur in the secondary system. The one-way check valve at the
inlet of the primary reservoir will close, preserving the primary air. The low air warning devices
will activate due to the air loss (either reservoir will trigger them.) As the pressure drops, the
governor will load the compressor, but that air will simply be pumped to atmosphere due to the
faulty secondary system.
Left click for animation
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