I got a call from a good customer of mine today regarding a slurry pump issue. This is a 16 hp 230V single phase submersible pump. It has a control panel with capacitors, circuit breaker, contactor, and a relay. The pump wouldn't start, and tripped the breaker upon trying to start.
I found that the coil on the start capacitor contactor was bad. So, I robbed the contactor from his spare control panel. When I engage the switch to start, the capacitors snap. Why???? When I left it running for about 3 seconds, one start capacitor started boiling.
So, I decided to install spare panel. Now the pump just hums and sometimes snaps at the run capacitors. Why??? It acts like a bad start circuit but all capacitors check out o.k. It is driving me crazy that I can't seem to figure out why this won't work.