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I was working in the gas station and had a scorched outlet. I removed the outlet. The white wire was jumped over to the bare copper wire. I have never seen this before, so I called an electrician. He said it's wrong and someone didn't know what they were doing.

So I wired new outlet correctly and plugged in my tester. And it said wired correctly. Then about four hours later the entire circuit failed but didn't trip breaker. What is going on and should the owner be concerned? I told him any time you lose power to a circuit and the breaker doesn't trip you should be very concerned. So what is going on?

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    "working in the gas station" == commercial environment == call a licensed electrician. This is NOT a DIY situation.
    – Ecnerwal
    Commented Sep 1, 2022 at 19:08
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    @crip659 Write that up as an answer. Commented Sep 1, 2022 at 19:30
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    ... and then delete your redundant comment-answer.
    – isherwood
    Commented Sep 1, 2022 at 20:52
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    @Ecnerwal Absolutely, commercial wiring means a licensed electrician as you said, but even worse is that it's a gas station which have extremely stringent requirements for electrical, for obvious reasons. I'm not going to touch this question with a 10' pole. Commented Sep 1, 2022 at 21:58
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    I’m voting to close this question because it's not just about a commercial installation (thus not Home improvement), but it's about a gas station and any electrical problems there could lead to big boom! This requires a licensed electrician to do any work - it's not a DIY situation in any sense of the term.
    – FreeMan
    Commented Sep 2, 2022 at 12:25

2 Answers 2

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The only reason for someone to jump ground to an outlet is that something happened to the neutral wire and they didn't want to find the problem.

Given that it lasted 4 hours after proper repair at the outlet, there is a loose connection or broken wire somewhere. Might be causing sparks somewhere.

Sparks and gas usually do not play nice together, but are fun to watch on YouTube.

As a unlicensed electrician, you, and the owner have no business touching it. Lawyers like people like you doing stuff like this. It's an easy payday for them.

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  • @Paul Just re read your question, think my answer might be partly wrong. You said the white/neutral was jumped to ground screw? That should kill that outlet(stop working/having power). It might have been done to jump neutral for another outlet/light, still bad.
    – crip659
    Commented Sep 1, 2022 at 19:46
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    I took "jumped to ground screw" to mean "white neutral wire goes to neutral screw and to ground screw. And in that case, an intermittent neutral problem someplace upstream would match the symptoms. Commented Sep 1, 2022 at 21:07
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Screw torques.

Working at a gas station you likely understand the importance of screw torques. What happens when someone torques their cylinder head bolts "by feel" instead of with a torque wrench? Yeah.

The same issue applies to screw terminals on the main electric conductors on panels -- we know that, and electricians use torque wrenches for that. However, recent science has proven it also matters on the little stuff!

So the burn-up of the first outlet might have been a sloppy socket (you'd know)... but it also might have been improper torque on the terminal screws.

And overheat of your replacement outlet might be the very same thing. Or it could be a similar failure elsewhere in the circuit. Presuming the same "last guy" did all the outlets.

Broken neutral?

The arrangement of jumpering neutral to ground is called "bootlegging ground". It is done for one of two reasons: a) the socket doesn't have any grounding and they need to fool a 3-light tester into thinking it's grounded.* Or b) the junction box is grounded, (and I would expect gas stations to use metal conduit which provides the ground path)... and the neutral wire BROKE. So they are stealing neutral from ground just to get the socket working again. And the burn-up was unrelated.

It's quite likely you wired it up correctly, using the neutral as intended, and then the same neutral wire failure that caused them to cheat before, happened to you. The right answer is to hunt down that neutral wire failure. The neutral bar in the service panel is a good place, but really, at this point we are beyond "simply changing a receptacle" and deep into where a licensed electrician MUST be used owing to the commercial rules.

* This is a bad idea where GFCIs are concerned, because it will break the GFCI's protection.

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    I don't know the implications of a broken neutral in the US electrical system, but here in Europe I would shut the whole gas station down if I suspect a broken neutral. Immediately. I would not want to take the risk of a capacitor inside a fuel pump to explode because of overvoltage...
    – orithena
    Commented Sep 2, 2022 at 9:15
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    @orithena well, it semi-works in North America because all our electric services locally derive earth with our own earth spikes, and then bond neutral to earth at the service point (typically circuit breaker panel). This bond is allowed to take the form of "all neutrals and grounds going to the same bus bar". Take a novice who doesn't understand the reasons, add a little anti-government paranoia, and they think it's completely redundant. Commented Sep 2, 2022 at 17:13

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