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#### awp

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hello.i wired my own house and everything works and no breakers trip but when im under the house i can take my meter and stick one probe in the ground and touch anything metal and read 4 volts. of course all metal things have a ground wire in common.if im sweaty there is a tingle.ive notified the power company.they said there side was correct.i can turn off my main breakers and still read 4 volts.the only way it goes away is if the power company disconnect their neutral.im confused.any input would be appreciated.

#### kbsparky

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3,370 Posts
Stray voltage in the ground. This can be a problem as you have discovered.

Think of it this way: Your pipes are not hot, the ground is. So when you touch your grounded pipes and the dirt at the same time, you can feel the tingle of the potential difference.

In the summer, when the weather is hot, and the ground is dry, it will get worse the drier the ground gets.

After a good rain, I'll bet the problem temporarily goes away. :whistling2:

#### Yoyizit

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i can take my meter and stick one probe in the ground and touch anything metal and read 4 volts.
if im sweaty there is a tingle.
Put a 100w incand. lamp across the 4v and measure it again. If the voltage drops to 2v there is about 10 Ω (resistivity of the soil?) in series with this voltage.
With this load you may see different voltages depending on what metal you touch, with lower voltages being farther from the source, if there is a single source.

Using your body as an ammeter:
"Tingle" = ~4mA, give or take.
4v/4mA = 1k skin resistance; pretty low for a small contact area, but you have damp, salty, skin.
No tingle = <1 mA means > 4kΩ.

See table 1 in this link.
http://www.easternvoltageresearch.com/datasheets/safety.pdf

#### awp

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Discussion Starter · ·
thanks for the info.what if i pull my meter and disconnect my side of the service entrance cable.this would completely isolate my house from the power company.then i will back feed my house with my generator.wouldnt this let me know if its a power company problem or just the way it is?

#### Speedy Petey

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NO! DO NOT even think about pulling the meter!!!

This is never EVER an option for a homeowner. That is a task reserved for someone who knows what they are doing and has the proper protective clothing/equipment.
Don't believe me? Ask someone who has had one blow up in his hands.

#### Yoyizit

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just the way it is?
All kinds of currents at all kinds of frequencies are flowing in the ground, some of which kills livestock.
http://en.wikipedia.org/wiki/Single-wire_earth_return

Ground resistance testers have provisions for finding a quiet place on the freq. band to make their tests.
If you have a battery operated oscilloscope or spectrum analyzer you can look in on all this.

Soares has written a classic book on this subject.

#### kbsparky

· Electrical Contractor
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Pulling the meter would have no effect on containing stray voltage. Since the neutral lines remain connected, any stray voltage readings would remain.

You have to get the POCO involved in this, since the problem is most likely on their end.

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