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The house I bought a couple years ago had a couple outlets in a small room in the basement that didn't work. Now I'm troubleshooting them. It's a finished basement so I can't tear down walls. There's a lot of troubleshooting already complete so I'll describe where I'm at now:

I'm at the first outlet in the circuit fed from my panel. With no power I have connected the hot and neutral wires at the outlet and tested for continuity: ok. I checked for resistance to ground: Infinite meaning ok. I've checked for shorts by testing the individual wires to ground: all ok. The breaker is fine. I even swapped breakers and not change. Symptoms: With open wires at the outlet (bare, not attached to anything), I read 120V between neutral and hot; I read ~60V between Hot and ground; I read ~60V between neutral and ground. I'm aware of ghost voltage and I have a Fluke meter set in LoZ mode. Measuring Hot to ground give me only a ~2.5V differential when I would expect to see ~120 Volts.

I was concerned about a borrowed neutral in the basement. The house was built in 1997. The power comes in from an underground feed from the city. The basement was finished a few years after that. I hooked my meter up to hot at the outlet location (measuring 60 volts) and proceeded to turn off and on all lights in the basement: no change. Then I had the wife systematically kill the power to EVERY breaker in the house one by one while I monitored for a change in the voltage on the goofy circuit: No change. Then I had her turn off every breaker except this one particular one. There is no power going to anything in the house except this one outlet (wires pulled off for measuring) now. No change: 60V hot to ground, 60V neutral to ground and 120Volt hot to neutral. I cannot see, or logically reason that there is anything between this outlet and the panel. No other circuits in the house are affected by this breaker, and with every single wire on the rest of the circuit disconnected, there is no power anywhere else. I'm at a loss. It's like there's something back feeding on the ground wire because I've pulled the hot and neutral wires off in the panel and I get no volts. So I pulled a outlet off a separate circuit on the main floor: Everything is normal.

My electrician friend over FaceTime suggested that I connect the ground and neutral wire at the outlet. It does make the problem go away, but I'm concerned that there is a potential that the ground wire while connected to neutral at the outlet creates a hazard if something were to short. And this is where the limit of my electrical knowledge leaves me. Thanks for reading and please help.

isherwood
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Jason
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  • Is it possible that they wired it in a series and not parallel? – norcal johnny Mar 26 '20 at 07:42
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    Sounds like your ground wire is disconnected and that is throwing off all your measurements. – Harper - Reinstate Monica Mar 26 '20 at 09:05
  • I cannot see how they can be wired in series. From what I can tell is the hot wire comes straight from the break to the plug. Same for the neutral. I will try to untangle the mess of wires and re-ground the ground wire. I've tugged on it and it seemed secure. – Jason Mar 26 '20 at 13:47
  • You said you flipped every breaker, what happens when you physically unplug everything from the other outlets? (Perhaps one of those is wired incorrectly and the neutral/ground connection is going through a piece of equipment?) – Duston Mar 26 '20 at 14:38
  • Plugs are on the ends of cords. You're talking about outlets or receptacles. – isherwood Mar 26 '20 at 14:48
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    Piuctures of the (open) panel are welcome, maybe higlighting the the involved breaker – DDS Mar 26 '20 at 15:08
  • Thanks for the edits...but I'm sure everyone knew what I was talking about. I will be more accurate in the future. @Duston there is nothing plugged into any outlet on the circuit. In fact I have disconnected every outlet and there is only unconnected wires hanging from the boxes. If I have the breaker on, this is the first outlet in the circuit. No other outlet locations show any voltage at all. I must deduce this is the first outlet in the circuit. If I measure voltage in the panel I get all the right voltages. If I measure the wires in the basement I should get the same readings but I don't. – Jason Mar 26 '20 at 15:15
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    You should have *on each end* 3 wires - hot/neutral/ground. Disconnect all 3 from the panel and all 3 from the receptacle (which you already did, but just clarifying for this test). Then check *at each end* for any voltage (non-contact tester first) - if you get *anything* then you have something cross-wired or shorted to another wire or *something* in the wall. If that shows clear, then check resistance/continuity *at each end separately* between every pair of wires. Everything should show *no connection*. If anything shows a connection, even a high-resistance one, then track down... – manassehkatz-Moving 2 Codidact Mar 26 '20 at 15:23
  • the wires - something messed up somewhere as it snakes through the wall. A nail puncture, insulation chewed by a mouse, something wrong somewhere. If this last test shows no connection between any pair of wires then I'm stumped. – manassehkatz-Moving 2 Codidact Mar 26 '20 at 15:24
  • I'll give that a shot @manassehkatz-Moving2Codidact. – Jason Mar 26 '20 at 16:42
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    The insulation measurement of the disconnected wires should be done with AC 50V~ or more. If the Fluke meter works with a low DC voltage for resistance tests (typical < 10V=), the result can be misleading since damaged cables in wet environment like basements can have a stark non-linear insulation resistance between the wires. What seems to be an unfinite resistance @5V= could be much less @200V~. – xeeka Mar 26 '20 at 18:36

2 Answers2

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So, I fixed it! The only wire I hadn't disconnected in the panel was the ground wire. As it turns out, the ground wire was broken somewhere in the home run cable. This means that the entire circuit was not grounded! This explains why I had a wandering ghost voltage AND why terminating the ground to the neutral made the problem disappear. I now am reading all the correct voltages. I had to run a ground wire from a switch that was above one of the other outlets. I've done lots of wiring, but I had never encountered a grounding and bonding issue like this. I appreciate all your guys' input. Hopefully, there may be someone out there that can figure out their issue by reading all of this. Cheers!

Jason
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    Good call to use a retrofit ground wire in this application! – ThreePhaseEel Mar 27 '20 at 23:51
  • Great job of tracking it down, and thanks for posting your answer! Please give yourself a check-mark to accept this answer so others know that there is a resolution. – FreeMan Aug 01 '20 at 15:43
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Trouble shooting from a distance :-( I agree 100 % with the advice to actually disconnect both ends and isolate the problem (trace the entire wire both ways to eliminate smoke alarms, ceiling fans, and lights. Assuming you measured 120 AC leaving the breaker.

I have found voltage like you describe once at an outlet, it was feeding back through a ceiling light because someone had used the neutral through the light switch to turn the light on and not the hot wire.

   In this case I do not know what it would do to your symptoms.  It was a long time ago that it happened yet it was difficult to find so I remembered most of the details 

This house also had three way switches connected that way which caused voltage readings that did not make

Any chance someone wired it incorrectly as a switched outlet?

Have you already tried trouble shooting the other way, all breakers off, then just the one on. At least you could eliminate all the other circuits from the start.

I know from reading your post that you have done quite a lot, and are probably pretty frustrated at the moment. I also understand some of what I said you may have thought of or tried.

 Sometimes starting over, pretending like you have not tried everything is helpful.  The theory is pretty straight forward so it is more of a matter of finding what was done wrong or disconnected.

I might pull each outlet and switch and look closely that it was wired correctly. Perhaps disconnect (isolate) the next circuit and see how that affects your voltage.

Good luck, be safe.
Just thinking
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  • That's what I'm concerned about and why I systematically killed every circuit in the house to see if the ~60V would change at the outlet. – Jason Mar 26 '20 at 16:09