Very high neutral ground voltage

[jkeyser14]

I just noticed that a GFI receptacle in my bathroom was measuring 25v neutral to ground (also measures 120 neutral to hot and 95 ground to hot). Nothing else on the house was on at the same time except for one light and the dryer which is on a different circuit. I tested a large number of other outlets and they were all fine. What could cause the high neutral to ground voltage on this outlet? What should I look for to chase down the problem?

 

[mrb]

hm thats an odd one. I am thinking bad connection on the ground, combined with high input impedance of digital meter showing the voltage.

 

[Torque1st]

hm thats an odd one. I am thinking bad connection on the ground, combined with high input impedance of digital meter showing the voltage.

+1 Sounds like a good case of capacitative coupling. Look for the bad ground connection. Make sure your meter is not showing millivolts.

 

[ymerej]

That is an odd problem. To find where it's coming from, I'd start by removing the GFI outlet and testing the bare wires at that plug... could be a bad plug? Then I'd go turning off other breakers in the house, isolating devices, etc. until you find it. There's probably some old wiring wearing thin somewhere in a circuit where the power wire is almost touching the ground wire, or a metal junction box.

 

[Mattlt]

That is an odd problem. To find where it's coming from, I'd start by removing the GFI outlet and testing the bare wires at that plug... could be a bad plug? Then I'd go turning off other breakers in the house, isolating devices, etc. until you find it. There's probably some old wiring wearing thin somewhere in a circuit where the power wire is almost touching the ground wire, or a metal junction box.

I'd second this approach - test the wires coming into the GFI with the receptacle removed. I have a feeling the GFI receptacle itself is faulty.

Also check this circuit back at the panel, find the voltage there.