30v between neutral to ground when power completely off

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ptonsparky said:
One particular receptacle circuit or all receptacle EGs?

Go through and disconnect all cable feeds. Remove their bonds. Wear your gloves.
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There’s 1 outlet in that room where it’s strong and when you move closer to the panel it fades off going down to what the sub panel reads

I’m just going to rewire a couple circuits and if it continues I’m screwed
 
Emerino22 said:
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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But these things end up grounded with things plugging into the wall (e.g. TV set, maybe a cordless phone receiver). Disconnect those utilities with the power off and see if the mystery 30V goes away. Then properly ground them where they enter the building via an intersystem bonding block, preferably outside directly to the GEC and not inside to a pipe or at the end of some long grounding path. Phone utilities are usually grounded somewhere, but if it is old it could be to a pipe or some circuit EGC.
 
I’m definitely trying them but I’ve spent so much time figuring it out that I probably would have wired in that section already.
 
You have voltage between two points that should be tied together: the grounding terminal of the receptacle and the grounding bar in the sub-panel.

Connect them together temporarily with a piece of wire. Either a breaker will trip, or the voltage will disappear.
 
LarryFine said:
You have voltage between two points that should be tied together: the grounding terminal of the receptacle and the grounding bar in the sub-panel.

Connect them together temporarily with a piece of wire. Either a breaker will trip, or the voltage will disappear.
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And if it doesn't trip, put the amp clamp on it to see if there is any current flowing on it. If the main is off, and you still have current, then its most likely a fault coming from your neighbor.
 
LarryFine said:
You have voltage between two points that should be tied together: the grounding terminal of the receptacle and the grounding bar in the sub-panel.

Connect them together temporarily with a piece of wire. Either a breaker will trip, or the voltage will disappear.
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I’ll do this on my next visit and KIT. Thank you!
 
Emerino22 said:
I’ll do this on my next visit and KIT. Thank you!
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If your meter is a fluke it usually has a frequency function. Please check the frequency of the 30v. If it’s not 60hz maybe the RF you spoke of could be the problem.

In your case this may be irrelevant since you are getting shocked but try to carry a meter with a mechanical needle or what was once called a wiggy. Many times especially on 3 way switch circuits you will get an induced voltage but it can’t drive a light.

otherwise I would shut off the main and check from where the ground rod conductor enters the house with an amp clamp
 
Disconnect ground wire from ground rod and check. If you no longer have the 30v mentioned I would say your ground is better than the utility company and you are get a feed back from another source. For example It could be a bad element in your neighbors water heater. and your ground is better than theirs.
 
I've only skimmed through this thread: Try measuring the current on the GEC at the ground rod, if you find appreciable current, this will point you where to look next. I have seen where a neighbor has an open neutral at their service, or at the POCO xfmr and their ground rod becomes their current return path, through the utility GEC at the pole, or through another customers system. One time, the SVC. drop was completely encased by a tree limb (grew around it) and the system neutral was severed. Another case in a neighborhood, where there is only 10' between houses, the aluminum direct burial (we call it direct failure) cable was nicked, then eventually failed. Current then began returning the the XFMR pad via the GEC. The ground rod was almost disintegrated from electrolysis. Another member mentioned a file water heater element, look for faulted well pumps at the neighbors, too. Well casings are excellent conductors, and if not bonded back to ground at the branch ckt. source, they can cause the problem you are finding.
 
I apologize for the lengthy quotes (please bare with me, I have the COVID-19 Blues).

Post #1 (Emerino22):
The issue is that the customer is getting shocked by the ground in one section of the house and I also just by touching the metal grounding components of the outlet with the thinner parts of my skin feel a burning shock. ... And also are saying that there is radio towers nearby and can hear the radio frequency coming in from the amplifiers when they play their instruments. ...The problem continues do you feel a shock on the metal part of the outlet that is ground even when you touch it with your screwdriver you’ll see a small spark just by touching it with metal.
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Post #6 (LarryFine):
Okay, what is your "earth ground"? A driven rod whose conductor you have disconnected?
The point is that voltage is being measured between two points that should be electrically bonded.
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Post #14 (Emerino22):
LarryFine said:
Another rod is useless. This only involves the main panel.
I still am asking what two points you're reading voltage between.
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Yea more than 2 is pointless. On the outlet in the bedroom I’m reading 30V AC from the neutral of the outlet to the ground of the outlet. When I do neutral to hot it’s surging from 122-130.
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Post #22 (Emerino22):
LarryFine said:
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?
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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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Post #29 (LarryFine):
LarryFine said:
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.
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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
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Post #49 (Emerino22):
LarryFine said:
You have voltage between two points that should be tied together: the grounding terminal of the receptacle and the grounding bar in the sub-panel.
Click to expand...

Connect them together temporarily with a piece of wire. Either a breaker will trip, or the voltage will disappear.
I’ll do this on my next visit and KIT. Thank you!
Click to expand...

Post #50 (dm9289)
Emerino22 said:
I’ll do this on my next visit and KIT. Thank you!
Click to expand...
If your meter is a fluke it usually has a frequency function. Please check the frequency of the 30v. If it’s not 60hz maybe the RF you spoke of could be the problem.

In your case this may be irrelevant since you are getting shocked but try to carry a meter with a mechanical needle or what was once called a wiggy. Many times especially on 3 way switch circuits you will get an induced voltage but it can’t drive a light.

otherwise I would shut off the main and check from where the ground rod conductor enters the house with an amp clamp
Click to expand...

I think LarryFine is correct. First, make sure the system is configured correctly (ECG Bonding is solid throughout the system up to the Main Panel). This will reveal most problems in a lot of situations.

Anyone old enough to remember having "Rabbit-Ear" antennas for their TV may have experienced the "Shocking Burn" described in Post #1. It's caused by RF Energy and the Skin Effect (Higher Frequencies conduct on the outer "skin" of a conductor). This time, I do think there's unusually high RF Energy being picked up in the conductors in this house. It seems to be in some kind of "sweet spot" or focal point.

With the power turned OFF, I would try dm9289's suggestion (test for Frequency between N - G). If you get more than 60 hz (if you can read it at all, it may be too high to read), you know it's RF Energy (or at least, not associated with the electrical system).

In this case (finding RF Energy), a solid EGC may not be enough. The conductors (both Hot & Neutral) may need grounded shielding (EMT, AC or BX Cabling). This should prevent the surging that seems to be occurring in the circuit. It's very troubling that this RF Energy is so strong. Are the neighbors experiencing anything similar?
 
Something occurred to me after writing my last reply. I've had one experience where I received a Burning Shock similar to RF Energy. It was from an Electronic Fluorescent Ballast. One of the leads came loose from one of the tombstones and was touching the fixture's enclosure. When I went to open the fixture, it gave me that Burning Shock.
 
Emerino22 said:
There’s 1 outlet in that room where it’s strong and when you move closer to the panel it fades off going down to what the sub panel reads

I’m just going to rewire a couple circuits and if it continues I’m screwed
Click to expand...
Lemme say, this thread is awesome. Here is what I can add. I am assuming that @Emerino22 is a competent electrician (so far, it sounds like he knows what he is doing). The RF aspect is where I will put my $ on this problem. Some years ago, I was called out to help the city electricians trouble shoot shocks coming from the parking lot lights. All power was locked out, and all equipment grounds were solid, but only as far as the base of the light poles. The very 1st thing I noticed was the transmission lines directly overhead. I stabbed a large screwdriver into the nearby lawn, bonded it to my man-lift, and then bonded it to my wrist. There was a full 580 vac, 180 hz being induced into the light pole heads relative to me and the dirt. As I descended the induced voltage dropped until I was again at ground level it disappeared.

You need to contact the neighbors and ask them how many watts their transmitter is, what frequency they use, and if they are willing to help run some experiments to eliminate this problem. The fact that it is strongest in one area makes me very certain that you have stumbled upon the perfect conditions to create a ground loop antenna. In theory, the neutral and ground only connects in the main service. But, electronic equipment that also utilizes power (like a large wattage stereo) can create other connections, thereby creating a ground loop. The factors that will affect the voltage is the distance squared to the transmitter, the angle of conductor crossing, the length of exposed conductors, and the transmission frequency. It just so happens the conditions are right in the area you identified.

Ask them to turn the transmitter on/off while measuring this voltage. 2nd, ask them to modulate the amplitude while measuring the voltage. See if there is any correlation between steps 1&2 and the measured voltage. If so, ask them to transmit on other random frequencies. Make sure the frequencies they use are not even multiples of the current frequency. Even multiples of the current frequency will likely also cause problems.

Hope this helps. We all wanna know how this works out.
 
I had a problem like this before it ended up being at the power substation down the street. I don’t what they did but they called my customer and told them that they had fixed something at their station, so when I went back it was fixed.
 
Is this an overhead service or under ground, and has the power company put the Machine on their wires coming from the transformer To test them. The coolest thing I ever seen on the job was when they tested the over head wires. I watched them smoke and burn.
 
Rdcowart said:
I had a problem like this before it ended up being at the power substation down the street. I don’t what they did but they called my customer and told them that they had fixed something at their station, so when I went back it was fixed.
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"So, that's what a bonding jumper does!" :unsure:
 
Hey guys! I’m still yet to go back. The last time I went I disconnected the ground rods from the main panel and turned off all power from mains and the problem continued. I called the customer to see how everything was so far and they said they heard a radio station channel coming from their fridge and recently burned out the fridge ugh! (Told them to buy surge protectors) Again there is towers about 2-300 feet tall about 5 houses down the street. They must be in that sweet spot like some of you noted. Maybe a construction biologist will have more answers. Thanks for the help I appreciated!
 
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