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I have a situation where I had a 1/3hp fan motor fry, when I went to replace the motor, which is powered by a 120 volt circuit which also powers a 120v circulating pump, I discovered that my volt meter reads 139 volts from live to ground, and about 40 volts from neutral to ground, but accurately reads 120 volts from live to neutral, why am I experiencing this difference in voltage,I checked to make sure the neutral and the ground are properly terminated at the panel, everything looks good, there is a 480Y277volt 3phase system in the building along with the 208Y120 3phase system, both are grounded to the water piping in the building, could these system be feeding each other through the ground.
 

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Ax grinder
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Welcome to the forum.:)

I would check to make sure that you have a proper system bonding jumper installed on the secondary side of the 208/120 transformer.

Chris
 

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I have a situation where I had a 1/3hp fan motor fry, when I went to replace the motor, which is powered by a 120 volt circuit which also powers a 120v circulating pump, I discovered that my volt meter reads 139 volts from live to ground, and about 40 volts from neutral to ground, but accurately reads 120 volts from live to neutral, why am I experiencing this difference in voltage,I checked to make sure the neutral and the ground are properly terminated at the panel, everything looks good, there is a 480Y277volt 3phase system in the building along with the 208Y120 3phase system, both are grounded to the water piping in the building, could these system be feeding each other through the ground.
1. In answer to your question NO.
2. At the panel measure A phase, B Phase and C Phase to ground what are the voltages?
3. It sounds like you have a ungrounded system or were measuring to a ungrounded (not properly bonded) surface.
4. What type of meter?
5. Dd you try a solenoid tester?
 

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I have a situation where I had a 1/3hp fan motor fry, when I went to replace the motor, which is powered by a 120 volt circuit which also powers a 120v circulating pump, I discovered that my volt meter reads 139 volts from live to ground, and about 40 volts from neutral to ground, but accurately reads 120 volts from live to neutral, why am I experiencing this difference in voltage,I checked to make sure the neutral and the ground are properly terminated at the panel, everything looks good, there is a 480Y277volt 3phase system in the building along with the 208Y120 3phase system, both are grounded to the water piping in the building, could these system be feeding each other through the ground.
I was wondering what the diff was between stray and phantom voltage . I searched the threads and came up with your question a while back. I also noticed that there were only 4 responses. I think that this STRAY VOLTAGE thing should get more attention. What causes it, and how do you get rid of it? Or, should you worry about it , at all?
 

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I was wondering what the diff was between stray and phantom voltage . I searched the threads and came up with your question a while back. I also noticed that there were only 4 responses. I think that this STRAY VOLTAGE thing should get more attention. What causes it, and how do you get rid of it? Or, should you worry about it , at all?
I'll check IEEE Dictionary for proper Def. Tuesday

Typically Stray Voltage is considered voltage on grounded surfaces or earth that is of sufficient EMF to cause problems, Farms in particular dairy farms are prime places where stray voltage causes issues, docks and swimming pools also have been know to have stray voltage issues. Most of these issues relate to improper bonding, shorts in conductors where the earth carries voltage or in some utilities with a earth ground at multiple locations.

Phantom / ghost voltages read here
http://us.fluke.com/usen/Support/ap...(FlukeProducts)&parent=AP_FUN(FlukeProducts)#
 

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Fried Bologna um um good!
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I always test with a solenoid tester first and then a voltmeter if needed. Ive found the dvm can have you thinking you have a problem when you don't.
 

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ive seen this before i tested it with the fluke t+pro it sounds like a floating neutral the neutral on the 120/208v transformer wasnt grounded causing the voltage to be a little weird. if there is no wire from XO of the 120/208v transformer to the case add one. if there is no wire from the transformer to building steel that needs to be there too. i believe sometimes transformers already have bonding jumpers installed but some dont. just about all of them i installed needed a system bonding jumper
 
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