Hot neutral on 120/208 secondary?

wwhitney said:
Ah, that makes it more interesting. What's the impedance of the LoZ meter? [For my own edification, I would be tempted to try the incandescent light bulb test, along with measuring the voltage drop across the light bulb if it glows. A 60W incandescent bulb is about 240 ohms.]

Anyway, that makes post #4 a good approach.

Cheers, Wayne
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Usually low enough to rule out voltage due to capacitive coupling.
 
Spacious Ideas said:
The A phase reads around 3v to ground. B and C read 205v ish to the same ground.
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That tells me there is a ground fault on A phase somewhere, apparently with about 3 volts drop between your measuring point and the fault.

A phase normally is 208 to the other two phases, that three volt drop is showing up in those measurements as well.

If you attempted to install bonding jumper while energized in this condition you will likely get a fireworks show when making the bond as you will be establishing the missing link to the neutral of the source for the fault current to flow.
 
kwired said:
That tells me there is a ground fault on A phase somewhere, apparently with about 3 volts drop between your measuring point and the fault.

A phase normally is 208 to the other two phases, that three volt drop is showing up in those measurements as well.

If you attempted to install bonding jumper while energized in this condition you will likely get a fireworks show when making the bond as you will be establishing the missing link to the neutral of the source for the fault current to flow.
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I watched a Mike Holt video that scared me and have been moving forward with caution and PPE. Always have but now I read voltages ground to neutral and read amperage on any main EGC’s at panel boards or distribution xfmr’s.
I also do not want to turn off power and install a #2 Cu SBJ per NEC and locate it via tripped branch circuit breakers when panel board is turned back on as well as xfmr.
Appreciate the input and that is what I started looking for and can’t find yet. I also do not want to become a path for current to flow through.
 
Here was the ground fault on A phase. It read about 20k ohms to ground, raceways, or enclosure.
Thanks for all the input and wanted to post the conclusion.
This made the secondary neutral hot, did not trip breaker on primary of 75 kva xfmr, or any breakers. No SBJ created the floating neutral which would not clear the ground fault.
 

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