I ran across a very frighful situation the other day. I had a 15 hp, 3ph., 230 volt motor on an air compressor burn up. As I was changing it, I noticed all the wiring inside was scorched. After the reinstall, I was speaking with our mechanic and he mentioned something that concerned me. He said that the breaker kept tripping on this a couple of years ago and our "electrician" checked it out and it hasn't tripped since. By the way, nothing tripped this time either, just blowed it clean.
Well I decided to trace down the circuit. So I opened the panel and found the EMPTY 50 amp breaker where it was supposed to be. It was now tied directly into the main lugs fed by a 225 amp main breaker. Needless to say my boss was very upset. I don't think he will be back here. This is one of the many cases that I have came across similar to this in the past year.
I guess this is one of those situations that I should have taken pictures.
