When should you release the safety override switch on a MC-7 air compressor?

Releasing the safety override switch on a MC-7 air compressor should occur after the oil pressure reaches 10 psi. This is crucial because the oil pressure indicates that the compressor is receiving adequate lubrication, which is essential for its operation. If the oil pressure is too low, it can lead to excessive wear or damage to moving parts of the compressor, risking malfunction or failure. Thus, waiting for the oil pressure to reach a safe threshold ensures that the compressor operates efficiently and safely.

The other options relate to different operational metrics that, while important for overall function, do not specifically pertain to the critical threshold for safe compressor operation like oil pressure does. For instance, air pressure and water temperature might be relevant to how the compressor functions but do not directly affect the immediate safety of the compressor’s components in the same way as oil pressure.