Weird voltage

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Gaffen99

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new jersey
Can anyone tell me how I could have 183 volt from neutral to ground and 120 volt from line to ground? The only thing I can think is open neutral on a split circuit? Any thoughts?
Thx
 
Can anyone tell me how I could have 183 volt from neutral to ground and 120 volt from line to ground? The only thing I can think is open neutral on a split circuit? Any thoughts?
Thx

You are on it but keep in mind that feeders and services are 'split circuits' as well so the open neutral could be in a feeder or a service.
 
Could this problem generate from the transformer?

Yes it could be internal to the transformer but it is much more likely that the neutral is open somewhere between the point you are measuring from and the transformer.

I would start at the service disconnect and take measurements there.
 
Could this problem generate from the transformer?
To the extent that the neutral might be open near the transformer, perhaps.
But since the POCO neutral is grounded very close to the transformer secondary connection, the very high neutral voltage shift you are seeing is more likely caused by an open neutral on the customer side of the POCO ground/neutral bond, and also on the load side of the ground/neutral bond at the service disconnect.

It is also possible, but unlikely, that there is an open connection inside the POCO transformer where the center point of the secondary winding is brought out to connect to the POCO wiring. That, however, would usually result in wild voltages between L1 and L2 and ground, not just a shift in the neutral voltage.
 
The neutral is floating !
I.E. not bonded to ground anywhere
so the voltage to ground could be anything.
The fact he measured 120 to ground suggests it is grounded somewhere. He just has a neutral conductor that has at very least some higher then desired resistance between point of measurement and the source.
 
I don't see how you can get over 120 from the neutral to earth or to an ungrounded conductor on a 120 volt system without a winding fault in the transformer.
 
Even a '120v system' can be delta w/high leg....

~RJ~
True, but even with a high leg it would take some very unusual conditions to have 183 volts from the neutral to earth.

We really need to know what the system voltage is and exactly what points were used when the voltage was measured.
 
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