used air compressor problems
Bill
Also, the pressure sw on most "home style" compressors handle the hi amp loads, directly, Furthermore, the motors are not exactly the best Q.
My recent experience:
A NEW 5hp/80 g.
Ran for about 3 mo's, and blew the breaker.
Pulled the wire connection cover, and found 1 of the motor leads, a cheapass 1/4" push on, had melted.
Found that the contacts in the pressure sw were toasted, too.
The cure:
1. Added a remote contactor from Grainger,[80A], triggered by the pressure sw.[Also, a new press sw.] This unloaded the sw., and put the hi amp startup load on the remote. [Startup loads can be 4-6X running amps.]
2. Cut off the cheapass 1/4" connectors, and used wire nuts on the connections.
I'd check the pressure sw, and the check valve in the top of the tank. If the check valve sticks, the motor will try to start under load..In this condition, the motor, contacts, wiring, won't last long!

