Phase Voltage to Ground Differences

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Leo1

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Los Alamos, NM
What if the most likely reason phase voltage on a 120/240VAC, single family dwelling differs between phases to the equipment ground. Each phase to neutral is approx. 118 volts. However, on phase A to equipment ground is approx. 147 volts and phase B to equipment ground is approx. 72 volts.
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infinity said:
Sounds like a poorly connected or missing main bonding jumper.
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Maybe even more likely a bad neutral connection in the service conductor somewhere. I'd expect more equal voltage most cases where main bonding jumper is missing, and there are no ground faults.
 
kwired said:
Maybe even more likely a bad neutral connection in the service conductor somewhere. I'd expect more equal voltage most cases where main bonding jumper is missing, and there are no ground faults.
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The phase to neutral voltage is approximately the same I would expect a bad neutral to have a wider difference. The connection to the EGC (where he has the problem phase to EGC) is with the MBJ.
 
infinity said:
The phase to neutral voltage is approximately the same I would expect a bad neutral to have a wider difference. The connection to the EGC (where he has the problem phase to EGC) is with the MBJ.
Click to expand...
Somehow I missed him stating phase to neutral voltage:blink: I almost asked what phase to neutral was.

I agree most likely looking at open circuit in EGC or main bonding jumper, as well as isolation from other grounded objects.
 
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