Old problem a new twist

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ELT#1

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Winston Salem NC
I was separating the grounds from the neutral bus after installing bonded ground busses in my 200 amp panel.
I had most all of the grounds pulled out and was carefully feeding them to the new ground bus.
I notice after several bites that one ground seemed to have a voltage on it.
I pull out the Fluke and sure enough it has 38 VAC on it.
I follow the black lead to the breaker and turn it off.
I then started checking outlets in the house to determine which one was off.
Well it turned out to be the GFI that fed the Fisher Paykel washer.
I pull the electrical cord that connects the washer to the outlet.
I returned to the panel and no more voltage.
Now I am baffled, should that GFI have tripped? I replaced the GFI with a new one.
No help, the ground was still there when the washer was plugged in.
I made a rig the isolated the ground on the washer cord and checked the voltage to ground.
It was still there.
I called my buddy that owned a FP washer and had him check his washer.
Well, guess what? His had 38 VAC on the ground also.
Now I am wondering if others have this problem. I know where there is one other FP washer and tomorrow I will check it for grounding voltages.
I would like to know if anyone has run across this in their daily work.
 
battery charger with same 'signature'

battery charger with same 'signature'

You washer likely has an inverter fed motor and a few nanofarads are added to ground for noise suppression, probably draws 2 or 3 mA thus creating a 'phantom' voltage. Caps likely sized to stay below the min 4 mA GFCI trip level.

have a 100A 12V (120 Vac input) battery charger -- is small and uses a PWM solid state power supply, and has some 0.2 uF noise suppression caps to ground. Cannot be used on a GFCI circuit as trips GFCI immediately.
 
Try measuring it with a low-impedance voltmeter.

Say, for example, you had voltmeter with a 10-megaOhm input impedance in series with a 20-megaOhm leakage path. You'd measure 1/3 of the line voltage.
But a 20-megaOhm leakage path will allow only 6 microAmps to flow -- far less than the 6000 microAmps needed to trip a GFCI, and not enough to cause injury or concern.
 
I also agree that likely not enough current to trip the GFCI.

4-6 milliamp that it will respond to is not a lot of current, but can still shock the poop out of you.
 
Do they still make these?

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~RJ~
 
A few years ago I bought a Klein voltage continuity tester, and I can’t stand it. The flashlight is a rather poor design. It turns on when it’s in your pouch and drains the battery. I did however eventually cut out the LED bulb so it wouldn’t continuously drain my battery.


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