Author Topic: Voltage through ground.  (Read 5031 times)

Offline magician59

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Voltage through ground.
« on: August 09, 2009, 08:36:41 PM »
While replacing a ceiling fan in my home (built cir.1982), I noticed a voltage in my ground at the original connection. This was among other issues that evidence sub-standard construction. I turned off the house main and still read about 81VAC on the ground. How do I proceed to remedy this?

Offline Repair-man

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Re: Voltage through ground.
« Reply #1 on: August 09, 2009, 08:51:25 PM »
This is bleed voltage coming from an un-grounded circuit somewhere in the panel. If the breaker box was grounded to a proper copper rod, this would not occur unless a circuit was improperly grounded feeding off of it. If you have  underground utilities, then you may need professional help here.
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Offline magician59

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Re: Voltage through ground.
« Reply #2 on: August 09, 2009, 09:05:13 PM »
Thanks for the prompt reply. Another question: If this is caused by a current bleed, why didn't my main breaker stop it? Shouldn't the main disconnect from the utility source?

Offline Repair-man

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Re: Voltage through ground.
« Reply #3 on: August 10, 2009, 04:51:52 AM »
Another question: If this is caused by a current bleed, why didn't my main breaker stop it? Shouldn't the main disconnect from the utility source?

Because the main breaker is connected to L1 and L2, not Neutral.

Breakers  are there to prevent overload.  (Except for GFCI's)
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Offline shieldcracker

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Re: Voltage through ground.
« Reply #4 on: September 28, 2009, 05:16:06 PM »
Repair man, magician said he shut off the house mains.
If he still has voltage readings with the mains off then his problem might be more serious.
Magician I have an idea of what could be happenin but I need to know exactly how you came up with  the 81V?

Offline Repair-man

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Re: Voltage through ground.
« Reply #5 on: September 28, 2009, 05:25:04 PM »
This is an old post...why are you trying to revive it? He apparently found the problem and failed  to report back, as is often the case.
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Offline shieldcracker

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Re: Voltage through ground.
« Reply #6 on: September 28, 2009, 05:40:57 PM »
Because the problem could be very serious indeed. Just think about what he said...

You wanna see old, go see your own reply to my question on the wax motor 8 months after it was posted!  8)

Offline Repair-man

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Re: Voltage through ground.
« Reply #7 on: September 28, 2009, 06:09:12 PM »
I'm not going to argue with you here, but JW revived the post with another comment that begged for an explanation.
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Offline magician59

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Re: Voltage through ground.
« Reply #8 on: February 22, 2010, 03:16:12 PM »
Sorry about the length of time for this thread guys...I didn't fix the problem, but other problems in the house took priority. To answer shieldcracker's question: I read the voltage between the ground and neutral. incidently, I didn't notice this problem until after an AC company replaced my condenser unit, and installed a separate cut-off for it.
« Last Edit: February 22, 2010, 03:19:34 PM by magician59 »

Offline jumptrout51

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Re: Voltage through ground.
« Reply #9 on: February 22, 2010, 04:52:37 PM »
You have a serious grounding problem,if you are grounded at all.
As mentioned about underground utilities. If you have UG wiring the grounding rod could have pierced a hot lead. This would cause voltage to ground and neutral with the main off.
When the condensing unit was changed and a new disconnect installed,did they also install a ground rod?
Have you disconnected the main,then read voltage,then start turning off breakers to see when or if the voltage goes away?
Take a Kid fishing.

Offline magician59

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Re: Voltage through ground.
« Reply #10 on: February 22, 2010, 09:13:35 PM »
I haven't done any such checking yet, but I'll get into it this weekend. I'll keep you posted (provided I don't get bit too hard!)

 

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