Understanding Stray Voltage

[MossRoad]

Don't use a metal chair.....

 

[GLyford]

So did the garage door opener solve this issue, or was it a separate issue?

That was Doofy talking about a similar experience, not Industrial Toys. (Post 36)

 

[Doofy]

I tried an electric freeze-proof bucket for an outside malamute. The bucket worked okay for a year then she stopped drinking from it because it was shocking her. I couldn't feel it when I'd stick my hand in. I've heard of the same problems with freeze-proof bird baths.

 

[hawkeye08]

I've had two incidents where I got bit.

First one was a farm where I grew up, taking a shower got bit when my foot touched the drain. I learned to keep my feet away from drain while showing. It would come and go, we finally figured it out, it only happened when one of the irrigation pumps was running (about 1/4 mile from house, pumping from pond filled by irrigation district. Turns out the insulation had rubbed off the large wires in metal conduit buried between the pump and its panel. That was so much fun to dig up (by hand) and fix. But no more shock when showing.

Second one was when we lived in 1952 travel trailer while we were building our current house back in 1993. The skin of the trailer was hot, my Mom was the first to get bit, the rest of us did not have an issue until one night I went outside barefoot to get dog in. Bare feet on concrete pad touching trailer side, it was a good bite for sure. Turned off power to trailer immediately and started troubleshooting in the morning. We found a hot wire from kitchen fan intermittently touching the metal housing.

We have an RV post about 100' from main panel, both have neutral and ground bonded and both have ground rods. This was done per inspector in 1993. I have been told all sub panels should not have neutral and ground bonded.

A question for those in the know,

Should a portable generator used to power a travel trailer have a ground rod? Should neutral and ground be bonded on generator? How about if used to power some things in house during a power outage (using extension cords, not tied into main panel)?

It will be interesting to see how this turns out for Industrial Toys

 

[MossRoad]

That was Doofy talking about a similar experience, not Industrial Toys. (Post 36)

Thanks, I blame the mixup on my hearing....

 

[Industrial Toys]

Actually the current in the neutral can approach zero if the current in the two legs are equal.

We aren't under the NEC but I am curious about the single point ground matter as another topic.

I will first locate that fencer.

I would then take some readings at the house just to see if the problem exists there too. If it is present, I may take off the conductors to the barn and see if the problem goes away. If not, I would probably suggest he call the Utility.

For context, it is a hundred year old barn, with sketchy wiring. The house is as old, but with 70s and newer wiring.

Under current conditions, I am curious if I grounded the Tin to the rod, would the potential on the electrical ground diminish or would I liven up the tin? Maybe both!

I like a HOT shower but not like that. You don't remember all the cuts on your hands until you grab those handles.

 

[Tractor Seabee]

IT, Grounding the building metal skin is a code requirement. AS mentioned before it is highly accessible and the skin forms a huge antenna to collect stray currents flying around in the ether. If it is in this case correct term is bonded to the ground rod and ground conductor it then has the same potential, so no tingle.

Ron

 

[3Ts]

A similar situation: My shop had a problem with tingles. I did not notice it because I always wore boots or heavy soled shoes. My daughter came out one time barefoot and touched my (cast iron) table saw and jumped! I measured 56 volts to ground, but only when it was running! Turned out that, on the second floor, one of the outlets, when it was pushed in to the wall had the sharp end of the ground wire punctured the neutral insulation. Fixed that and all was good. The shop is on a different circuit than the 2nd floor, but off the same sub-panel.

 

[Belevolk]

Actually the current in the neutral can approach zero if the current in the two legs are equal.

We aren't under the NEC but I am curious about the single point ground matter as another topic.

I will first locate that fencer.

I would then take some readings at the house just to see if the problem exists there too. If it is present, I may take off the conductors to the barn and see if the problem goes away. If not, I would probably suggest he call the Utility.

For context, it is a hundred year old barn, with sketchy wiring. The house is as old, but with 70s and newer wiring.

Under current conditions, I am curious if I grounded the Tin to the rod, would the potential on the electrical ground diminish or would I liven up the tin? Maybe both!

I like a HOT shower but not like that. You don't remember all the cuts on your hands until you grab those handles.

The Canadian Elec Code is not all that much different than the NEC. Single point grounding is the accepted simple method of a grounded electrical system. There are ungrounded electrical systems, that is way different subject. There is a section in the Codes that allows for a supplemental grounding, how ever I have seen electrical engineers run afoul trying to use that section. Driving a ground rod at your remote building is a marginal idea. If this ground rod is connected to the ground coming from the service on your home you have just entered into supplemental grounding. Reason most do not use it is because the conductor between the barn and the elec service has to be the same size as the elect service ground, surely not a 10 awg like you have.
Having voltage between the ground rod and the building tells me that your building sub panel or load is leaking voltage. Your sub panel at the building should have the neutral and the ground isolated from each other. Shut off the power and use an ohm meter to be sure there is no connection. Quite common to have a screw in the neutral block that lands into the sheetmetal so the panel could be used as a service. You will need to lift one of the wires or you will read to your service and back. You should not get a reading, 0.00. Your sub panel should be bonded to the building. Bolting the sub panel to the building sheet metal should be good enough. Be sure that the neutral/grounded conductor has no connection to the ground at any of your loads.
The only thing I can think of that may be a issue is the conductors from the house. Romex is not rated to be underground even in conduit. Time and water will destroy the outer sheath and eventually work into the cable and cause problems. This can be tested by using a 1000 v megger, not an ohm meter. You test phase to phase, phase to neutral and ground, then ground to neutral. Circuit needs to be dead and removed from both ends for this test. Anything over a megohm would be satisfactory. Anything less, well that is a longer story. Might be time to consider a new feed. I do not remember all of this thread, did you test for voltage between the ground and neutral at the barn? We tested trailing cables in the mine at 5000v and wanted a gigohm of resistance. Voltages on those cables were either 4160 or 7200 ac

Grounding the tin to the ground rod is creating a difference of potential, very bad for living creatures especially horses.

 

[aczlan]

A question for those in the know,

Should a portable generator used to power a travel trailer have a ground rod? Should neutral and ground be bonded on generator? How about if used to power some things in house during a power outage (using extension cords, not tied into main panel)?

It will be interesting to see how this turns out for Industrial Toys

If it is connected just to the travel trailer, or to an extension cord, it is considered a separately derived system and would need to be bonded at the generator.

Aaron Z