120V on Neutral to Ground

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Anonymous
120V on Neutral to Ground 2016-02-20 01:44:57 Post No. 949218
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120V on Neutral to Ground Anonymous 2016-02-20 01:44:57 Post No. 949218 [Report]

I am trying to help my mom figure out what's wrong with her circuit. I know some electrical theory, but I'm shit at troubleshooting.

If I disconnect the underground cable from the 1st outlet, the 1st outlet reads as being completely normal. But when the underground cable is connected, as is normal, the lights only flicker occasionally; and more to the point, on the 2nd outlet I'm reading 120V hot to ground (okay, that's normal), and 120V NEUTRAL to ground (~0 volts in between hot and neutral). This problem just developed all of the sudden, it was working fine before. I understand the reason the lights are only flickering is that there is almost no voltage differential between hot and neutral, so no power is flowing through the bulb.

My first thought was that the underground cable got damaged, and the hot is energizing the neutral, but I kinda thought that would just trip the breaker, which is not happening... Any thoughts besides "replace the underground cable"? (I am planning to buy an Outlet Tester in case something like this happens again, but don't have one now.) Maybe the neutral is open in the J-box?? I wanted to look at things longer, but was freezing my ass off out there.

Greatly appreciate any thoughts.

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Anonymous 2016-02-20 02:19:02 Post No.949230
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Anonymous 2016-02-20 02:19:02 Post No.949230 [Report]

>>949218
replace the cable, it's fucked

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Anonymous 2016-02-20 03:04:03 Post No.949253
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Anonymous 2016-02-20 03:04:03 Post No.949253 [Report]

>>949218
Did you get 120 neutral to ground with the light switched on or off?
A loose neutral could cause flickering, if you measured with the light switch on but the light bulb off you would get 120v neutral to ground because no current was flowing. So that's my guess is a loose connection. Check all the connections.

If you want to check the cable you can rent a proper tester that dumps high voltage through the cable to check insulation resistance as well as conductor impedances etc. Standard electricians kit.

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Anonymous 2016-02-20 03:20:48 Post No.949267
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Anonymous 2016-02-20 03:20:48 Post No.949267 [Report]

>>949218
Is there a possibility that you rolled wires somewhere? Could be that you have hot switched to ground at the J-box which would give you 120V to the L/N terminals at the outlet. Just speculation.

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Anonymous 2016-02-20 03:59:48 Post No.949299
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Anonymous 2016-02-20 03:59:48 Post No.949299 [Report]

>>949218
>My first thought was that the underground cable got damaged, and the hot is energizing the neutral

That's my guess. That or a bad connection.
Check the wire by disconnecting it from both ends, twist the wires together on one end, then check with an ohm meter from the other end.

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Anonymous 2016-02-20 12:48:10 Post No.949463
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Anonymous 2016-02-20 12:48:10 Post No.949463 [Report]

>>949253
Both with the light on and off.

>>949299
Ah, I like that idea. Easy to check the whole circuit for an open wire somewhere.

Thanks, all.