Livestock Water Tank

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Have you explored NEV? Your original post that stated the same volt to remote earth both at barn and at watering trough lends itself to exploring that option. If it is NEV your other fixes maybe futal, checking NEV is a fairly simple process, process will also confirm an issue generating from something withing your system or coming from other source including POCO. Mike Holt in is educational materials goes into detail on the proceedure and why NEV it affects farm animals.
Turning off, disconnecting all local power and repeat your original tests, if voltage disappears it is a local equipment issue, if voltage remains coming through neutral from utility. If local issue you can isolate the source by selectively returning power to individual circuits to see the one causing issue. Well pumps are a common culprit as mentioned in post #7.
 
Thanks for the help. Here is an update:

If a tester shows a good ground, but it could be a bootleg how does one really know if the ground is up to snuff. Visual? We are going up date the panel in the shop with a breaker box and will run new wires to the outlets and see if that solves the problem. He did call me and said the smaller cord does not have a ground pin. This is the cord that removes the voltage to ground whereas the newer cord with a ground pin brings back the voltage to ground. The water tank is plastic and the heater is new out of the box.
More evidence that there is elevated voltage on the EGC wherever you are plugging that cord into.

I'd be checking neutral to earth voltages (or EGC to earth if a building is supplied by a feeder with a separate EGC) at this shop, and every junction back to the utility supply if you keep seeing similar voltage readings. If you have this kind of reading at the main pole or whatever is your utility main, then the problem might be coming from POCO side. Voltage drop on their MGN is passed on to everything bonded to it, which includes your service neutral conductor which ultimately bonds to the EGC of your branch circuit somewhere.
 
If a tester shows a good ground, but it could be a bootleg how does one really know if the ground is up to snuff. Visual?
Yep, look at pretty much every place the could be a connection to see if there is and should be/etc; that is, check the entire system.

He did call me and said the smaller cord does not have a ground pin.
Aha! Comparing apples and grapefruit. (Never completely trust what the customer says, lots of threads here about that.)

There's still the question of a ground fault on the heater; if nothing else, try it on a gfci outlet when it's in the water and see if that trips. AFAIK that's still too much current for around cattle, but it's easy to do.
 
Yep, look at pretty much every place the could be a connection to see if there is and should be/etc; that is, check the entire system.


Aha! Comparing apples and grapefruit. (Never completely trust what the customer says, lots of threads here about that.)

There's still the question of a ground fault on the heater; if nothing else, try it on a gfci outlet when it's in the water and see if that trips. AFAIK that's still too much current for around cattle, but it's easy to do.
If there is rise in voltage on the EGC a GFCI will not respond to it.

If there is a ground fault in the heater the GFCI will trip even if there is no EGC in the cord, unless there is no return path at all - which is more possible with a plastic tank or metal tank isolated on plastic frame of some sort.

The fact there is voltage to ground when there is an intact EGC in the cord - tend to make me believe the EGC is what is bringing voltage out to the water tank location. The cause could be at the building it plugs in at or if on a farm with multiple buildings anywhere upstream or even in POCO supply system.
 
"how does one really know if the ground is up to snuff."

By using a clampon ammeter.

If no current flows in the ground conductor with everything switched on or off and all combinations of this, the conductor is serving no purpose.

If we are looking for 2 mA or less to make the cow skittish, you’d need a clampon that can resolve 1 mA or so.
Amprobe makes one.

To resolve the 1 mA you need to turn everything on or off in all combinations and look for the change.

Let’s say we have two voltage sources, one tank heater (240v?), and PoCo.
Assuming PoCo stays on, here’s the combos.
0 means off, 1 means on.

V1 V2 Heater
0 0 0
0 0 1
0 1 0
0 1 1
1 0 0
1 0 1
1 1 0
1 1 1

8 tests in all.
With 3 voltage sources it’s 16 combos.

With a helper 8 tests might be a half hr job.

Note that adding more grounds may make things worse or show no change.

I hope the rancher's insurance covers losses to cattle. It's not an Act of God, war, or civil unrest. If you get ground conductor current with everything off, It could be an Act of PoCo!
 
If the cord with the ground conductor always solves it, measuring the current in that ground wire may give you a clue as to the root cause.
You have that backwards. He said the 14 cord had no ground pin and that when it was used, the voltage problem went away.
 
I understood that it was on again, off again with either cord.
Your take would sure point to a neutral problem.
He chimed in later with additional info and said the cord being used when there was no stay voltages present had missing EGC pin. Tells me right there the stray voltage is originating from EGC, but exactly where (somewhere upstream from where it is plugged in) is yet unknown.
 
If you or your customer absolutely cannot find the problem, then this is the solution...........


No freezing, no electricity involved. Oh yes.........just don't plumb it with metal piping.
 
If you or your customer absolutely cannot find the problem, then this is the solution...........


No freezing, no electricity involved. Oh yes.........just don't plumb it with metal piping.
Some of those types will freeze if there isn’t enough water usage.
 
Check for bad neutral supplying the shop, or elsewhere in the distribution to the shop. Any rise of volts to ground on the supply neutral will raise all EGC's to ground that are connected downstream from it.
To the OP, IMO this ^ is the very next thing to do. If you need assistance in methodology of how to do this, ask and I'm sure you will get answers.
 
I would not eliminate the possibility of NEV but I would be checking out all the wiring and meggering the feeder first. One thing for sure is that driving a ground rod was a complete waste of time and resources as it always is.
If he drove it next to the watering tank (instead of at the source) and bonded the water to the ground rod it might be a different outcome.
 
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