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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.

  • Is it possible that they wired it in a series and not parallel? – norcal johnny Mar 26 at 7:42
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    Sounds like your ground wire is disconnected and that is throwing off all your measurements. – Harper - Reinstate Monica Mar 26 at 9:05
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    Piuctures of the (open) panel are welcome, maybe higlighting the the involved breaker – DDS Mar 26 at 15:08
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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 at 15:23
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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 at 18:36
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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!

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    Good call to use a retrofit ground wire in this application! – ThreePhaseEel Mar 27 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 1 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.
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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 at 16:09

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