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What does the air compressor governor do once air tank pressure reaches its cut-out setting, which is typically around 125 psi?
- A.It unloads the compressor so it stops sending air to the tanks until pressure falls again
- B.It locks the spring brakes on automatically
- C.It dumps all air from the tanks to clean out moisture
- D.It raises compressor output to 150 psi and holds it there
Correct answer
A. It unloads the compressor so it stops sending air to the tanks until pressure falls again
Why
The governor controls when the compressor pumps and when it idles. At cut-out, near 125 psi, it unloads the compressor, and it cuts the compressor back in when pressure drops to roughly 100 psi.
Manual topic: Air Brakes - Air Compressor and Governor · From the General Knowledge practice bank (GK-101).