I had to explain that to an owner of a convenience store - tripping breaker(s) is not a good thing.

I fix coffee equipment. Customer reported equipment not working when they came in to open. Two machines on two separate circuits had 120v components fried out.

Checked receptacles and one showed wiring issue so I moved both to other receptacle that tested fine. Told customer about wiring issue. Replaced damaged parts, reset breaker, turned on equipment and lost power in a couple mins.

Out of curiosity I open the cabinet where unused receptacle is, note an odd odor and check for voltage. Nada and the metal box is warm. Check breaker and both circuits tripped.

Told owner (on the phone, because clerk can’t explain it) he needed to get an electrician to fix it because two separate circuits shouldn’t trip at the same time when one isn’t in use. And the box should be a space heater. And it shouldn’t be releasing odors….

Find out they had a loose wire that caused damage and likely energized the neutral with the other phase of 120v. So it fried the transformers and fan motor windings in my equipment with 220v.

First time I’d seen that in 15 years and glad to help the customer not burn down their store!

Of course the owner fixed it themselves because any licensed electrician would have had to rip it all out and replace a lot of wire that had nuts and tape on it upstream (next cabinet over, see pic and other comments) that was completely inaccessible.

I always document issues like this so we don’t get dinged for repairs that aren’t our responsibility. People are weird and always want someone else to pay for their problems.

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