Compressor governor tanks1 of 2
What does the air compressor governor do when tank pressure reaches the cut-out level?
The answer
Answer: C. At the cut-out point, roughly 125 psi, the governor halts compressor output so the tanks do not keep rising. When pressure later falls to the cut-in point, about 100 psi, it lets the compressor pump again. Opening the safety valve is a separate protection that works only if the pressure keeps climbing past the governor's setting, and draining the tanks is a manual job done at the end of the day.
Source: 5.1.2 - Air Compressor Governor