voltage to ground question please help

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On a 120 volt circuit that is showing open grounding conductor with plug tester and a grounding conductor does exist and connected to the green screw hot to neutral shows 120 volts, hot to grounding conductor shows roughly 60 volts and neutral to grounding conductor shows roughly 60 volts. Is this okay and normal for a neutral to show voltage to an open grounding conductor? Is it okay to plug a new microwave into this circuit? Would this odd voltage from neutral to open grounding cause an appliance to short circuit components?

Confused please help
 

Dennis Alwon

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First thing I think of when we get voltage between the neutral and the equipment grounding conductor is an open neutral. Are you sure there is 120V neutral to hot when a load is on it.
 

GoldDigger

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It sounds like the main bonding jumper doesn't have a good connection.

Given that there is a bond at the POCO transformer secondary, a problem with the main bonding jumper would only affect fault current, not the normal voltage difference between neutral and ground. At least not up to 60V (which is probably a phantom voltage anyway.)
 

Little Bill

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Given that there is a bond at the POCO transformer secondary, a problem with the main bonding jumper would only affect fault current, not the normal voltage difference between neutral and ground. At least not up to 60V (which is probably a phantom voltage anyway.)

I actually had written there may be a phantom voltage but edited it.

I disagree concerning the bond at the transformer. The EGC doesn't go back to the transformer. So if the GEC is landed on the neutral bus and the jumper to the can or ground bar is loose or not there you can read a voltage between EGC & neutral.
 

J.P.

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United States
Is this a new install or something with recent construction?


In a lot of case with older houses a new outlet will get added with new style wire. The ground wire wont go anywhere, just to the box they got power from.

If you personally ran this wire from the panel to the outlet.....loose connection or possibly a nail or screw though it.

I'm guessing it may be the first one though. It should be safe to use. You should use a GFI recep though.
60v is a non reading. induced or phantom voltage.

You could ohm the neutral to the ground. You will ring through the bonding if everything is ok. If it doesn't ring..........your ground wire isn't making it to the panel.
 

JFletcher

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Location
Williamsburg, VA
On a 120 volt circuit that is showing open grounding conductor with plug tester and a grounding conductor does exist and connected to the green screw hot to neutral shows 120 volts, hot to grounding conductor shows roughly 60 volts and neutral to grounding conductor shows roughly 60 volts. Is this okay and normal for a neutral to show voltage to an open grounding conductor? Is it okay to plug a new microwave into this circuit? Would this odd voltage from neutral to open grounding cause an appliance to short circuit components?

Confused please help

You probably have a false or open ground. re: N-G reading 60V, was everything else on that circuit unplugged or off?

If, as JP wrote, this is a new outlet added to older wiring, you very well may have no ground. In addition, I'm going to guess that it's jumped off of something else with more than a nominal load, and a tripped breaker will be the end result. Also, if it's a fixed mount microwave, it needs a dedicated receptacle
 
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