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30v between neutral to ground when power completely off

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Emerino22

Member
Location
Los Angeles
Occupation
Electrical contractor
Y'know this may be as simple as a grounding receptacle on a 2-wire circuit, or it may not be.

That's one reason voltmeters aren't as good for most troubleshooting as solenoid testers.

That and dragging around the female end of an extension cord plugged into a known-properly-wired receptacle against which to test.



Added: No, on second thought, that wouldn't provide enough current to provide shocks. Maybe it's RF energy?

What are you reading hot to ground at the receptacle?
Yea I checked all connections everywhere and I’m mind blown (outlets, lights, switches, went to crawl spaces and attic)
Can RF energy do this? Remember everything is off and I’m still getting voltage and in that specific room the ceiling is metal and the radio towers are about 500ft away.

forgot to add 122-130v on recep from hot to ground surges the same. FYI it’s on a gfi in the bedroom someone added due to the problem.
 
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LarryFine

Master Electrician Electric Contractor Richmond VA
Location
Henrico County, VA
Occupation
Electrical Contractor
Yea I checked all connections everywhere and I’m mind blown (outlets, lights, switches, went to crawl spaces and attic)
Well, don't keep it a secret. What's feeding the receptacle? Old cloth-covered rubber? NM w/ gr? NM w/o gr? BX cable?

Can RF energy do this? Remember everything is off and I’m still getting voltage and in that specific room the ceiling is metal and the radio towers are about 500ft away.
Absolutely. Try running a temporary ground wire from the ceiling to a known electrical ground, or from the receptacle ground to a known ground.

What could be the connection (pun intended) between the ceiling and the receptacle? A non-grounded EGC between the ceiling box and the receptacle box.
 

Hv&Lv

Senior Member
Location
-
Occupation
Engineer/Technician
You have voltage from neutral to ground with the POWER OFF.
neutral and ground are separate everywhere except main panel and POCO connections.

I would check the voltage with the power off at the meter base. Separate the rod and check it. From there call the POCO. If they have a bad connection it can cause things to seem haunted from neighbor to neighbor...
 

synchro

Senior Member
Location
Chicago, IL
Occupation
EE
Yea I checked all connections everywhere and I’m mind blown (outlets, lights, switches, went to crawl spaces and attic)
Can RF energy do this? Remember everything is off and I’m still getting voltage and in that specific room the ceiling is metal and the radio towers are about 500ft away.
You typically won't get what feels like a shock with RF current because the current flows on the surface of your body and not through the nervous system. In this case the "skin effect" can be taken literally.;)
You can get an RF burn if there's enough current concentrated in a small area. These effects can be observed with a Tesla coil. If you grab a larger piece of metal such as a wrench you can draw RF sparks without getting a burn because the wrench spreads the RF current over a larger area of your skin. Obviously if there's enough RF current you will get a burn in any case.

Are the antenna towers several hundred feet tall, such as with AM radio stations? Amplitude modulation is readily detected by nonlinear circuit elements in amplifiers, etc. so that you can end up hearing it. Frequency modulation is more difficult to detect.
 

Emerino22

Member
Location
Los Angeles
Occupation
Electrical contractor
Well, don't keep it a secret. What's feeding the receptacle? Old cloth-covered rubber? NM w/ gr? NM w/o gr? BX cable?


Absolutely. Try running a temporary ground wire from the ceiling to a known electrical ground, or from the receptacle ground to a known ground.

What could be the connection (pun intended) between the ceiling and the receptacle? A non-grounded EGC between the ceiling box and the receptacle box.
It’s NM W/G 12/2 feeding it.
That room is the furthest room from sub panel. I tried running a new NM W/G 12-2 Romex directly from sub panel and the reading was a little different on the new recep ground to neutral. I would walk around with the recep and the numbers would go from 12- 20. 20 being closer to the suspect recep
 

Emerino22

Member
Location
Los Angeles
Occupation
Electrical contractor
You typically won't get what feels like a shock with RF current because the current flows on the surface of your body and not through the nervous system. In this case the "skin effect" can be taken literally.;)
You can get an RF burn if there's enough current concentrated in a small area. These effects can be observed with a Tesla coil. If you grab a larger piece of metal such as a wrench you can draw RF sparks without getting a burn because the wrench spreads the RF current over a larger area of your skin. Obviously if there's enough RF current you will get a burn in any case.

Are the antenna towers several hundred feet tall, such as with AM radio stations? Amplitude modulation is readily detected by nonlinear circuit elements in amplifiers, etc. so that you can end up hearing it. Frequency modulation is more difficult to detect.
Good to know! Customer says it’s an AM station that broadcasts to another country. The antennas are pretty tall and go up probably idk 500ft and there’s 5 of them.
 

Emerino22

Member
Location
Los Angeles
Occupation
Electrical contractor
You have voltage from neutral to ground with the POWER OFF.
neutral and ground are separate everywhere except main panel and POCO connections.

I would check the voltage with the power off at the meter base. Separate the rod and check it. From there call the POCO. If they have a bad connection it can cause things to seem haunted from neighbor to neighbor...
I will try this. Seperating the rods with all power off and see what happens. Next step complete rewire probably something in the walls causing all this. (Talking about haunted customer has satan pictures all over the house)
 

Emerino22

Member
Location
Los Angeles
Occupation
Electrical contractor
That’s what it’s sounding like, possible bad gfi up stream giving the fluctuating voltages on hot to neutral.
Can a bad GFI up the voltage? I didn’t replace them. Another good idea but I’ve never seen this
I’ve had meters in the past that couldn’t tell the difference between AC and DC. Is yours up to the task?
what meters do you recommend?
The solar system would add to my problems.

The neighbor may be the one with the problem especially with a shared metallic water pipe from the utility.
i opened all solar connections to see if anything was fried and nothing. I also had another engineer tell me it can be the POCO transformer.
 

LarryFine

Master Electrician Electric Contractor Richmond VA
Location
Henrico County, VA
Occupation
Electrical Contractor
Have you measured the voltage between the receptacle's ground and the panel's ground?

It should be zero at all times.
 

LarryFine

Master Electrician Electric Contractor Richmond VA
Location
Henrico County, VA
Occupation
Electrical Contractor
I’ll try that. If it’s not the same as the panel it will be an open ground?
Yes. I'm guessing that the receptacle EGC is floating. What's the hot-to-ground voltage? Will it light a bulb?

Think about how it would be wired as a new job, figure out what's missing as it is now, and correct the omission.
 

suemarkp

Senior Member
Location
Kent, WA
Occupation
Retired Engineer
One other things to check -- are there grounded utility wires coming into the house (e.g. telephone cable, CATV cable) that are connected to the grounding system? Those can act as antennas too and dump voltage onto your ground. Curious if the branch circuit wiring is acting like an antenna, that metal ceiling, outside utilities, something else, or all of them.
 

Emerino22

Member
Location
Los Angeles
Occupation
Electrical contractor
Yes. I'm guessing that the receptacle EGC is floating. What's the hot-to-ground voltage? Will it light a bulb?

Think about how it would be wired as a new job, figure out what's missing as it is now, and correct the omission.
I have more searching although I opened all boxes in the complete house. But it’s strange how when everything is shut off there’s still voltage on the recep ground to neutral.
 

Emerino22

Member
Location
Los Angeles
Occupation
Electrical contractor
One other things to check -- are there grounded utility wires coming into the house (e.g. telephone cable, CATV cable) that are connected to the grounding system? Those can act as antennas too and dump voltage onto your ground. Curious if the branch circuit wiring is acting like an antenna, that metal ceiling, outside utilities, something else, or all of them.
Non of this equipment was properly grounded that I saw. The telephone system was on that side where the issue is and the panel is on the opposite corner of the house.
 
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