New pool with electrical shock

[BigDave]

Do you have the 1.4V between the ground and neutral busses in the Service Panel? These busses should (code around here) be strapped to each other in the service entrance panel (but not in any sub panel). Ground and neutral are also usually connected together in the meter pan where the neutral/ground connection connects neutral to the driven ground. I would make sure that neutral is properly electrically connected to ground in the service entrance panel and in the meter pan as this is important to the safety of the electrical circuits in your home. I'm not sure that adding additional driven grounds will help, it may worsen any ground loop problem.

Is the light supplied from the sub-panel that supplies all other pool-touching circuits?

Ben is right (of course) that bonding the entire pool, pool water, and pool area (including every bit of metal larger than 4") should alleviate any shock as everything swimmers touch will be at the same potential.

[Jimmy C]

I had a similar problem. Went to change under water pool light, so turned off light switch, and breaker to GFCI circuit. Then measured no voltage black to white and either to ground. Safe to proceed right? There I was no shirt, tits on the wet ground removing pool light bezel. As soon as I detached it I started sizzling. Turned out the power coming off the utility pole had the bare neutral wire severed by a tree branch. The house ground was my pool, and the connection was at the light!! Any resistance in the neutral wiring back to the utility transformer can put voltage on neutral. Since neutral and ground get bonded together at main box, having a volt or two difference between pool ground an power ground is possible especially if the pool is far from the house. Sometimes the difference can be traced to a well pump that has lost its insulation, and is supplying current into the soil surrounding the well. Just some random thoughts! Jim

[Poconos]

I don't have any comments on how to solve your problem but am curious where your house and pool are located in relation to other houses. When I lived in New Jersey in a housing development you could stick a couple rods in the ground and get a voltage reading. Here in the country I get nothing. Ben touched on it when he was talking about power companies using the earth as a conductor. They don't do it intentionally but it is a fact of Ohms Law. Residential power is supplied by the live high voltage line and a neutral, or return, strung on the poles or underground. A transformer drops it to the 120/240 single phase for the house or houses. Because houses have these 'neutrals' connected to water pipes etc, part of the power distribution systems return current will flow through the earth thus creating a potential difference between your house and a neighbors. If neighbors are close this voltage gradient in the earth can be high. In the country with houses far apart it is a lot lower. Theoretically if all your pool equipment, rails, etc were connected to your service entrance neutral with a good heavy, low resistance wire, you shouldn't see this gradient.
I'be babbled enough.
Al

[Jimmy C]

From original post:

"As it turns out, the voltage is coming from the ground (bare) wire from the #6-3 feeder from the service panel - even when the house is completely disconnected from the power line. BTW - the sub-panel has two buses - the ground wires are connected to one and the neutral wires to the other - When we connected the #6-3 ground to the neutral bus the shock stopped - but that doesn't meet code."

The crux of the problem is in this statement. Both neutral and ground should be tied together at the main panel, and left separate at sub-panels. I'm not an electrician, but does #6-3 imply three wires #6, or 3 wires #6 and a ground? If it the last one, is the gauge of the ground wire the same (#6)? If we can eliminate the problem by jumping neutral and ground at the sub panel (not code), we should look upstream to the main panel. Are the two connected properly there? If so, take a meter from that point to a nearby ground rod (could be temporary 12" rod for this test). Is there any voltage from rod to main panel junction of neutral an ground? See illustration at the following link:

http://edis.ifas.ufl.edu/ae019

The dairy industry has similar issues where cows are extremely sensitive to stray electrical currents flowing in the soil, or concrete.

You might need a substantial buried ground plate(s) at the main panel. See link here:

http://www.erico.com/products/GroundPlates.asp

Jim

[Jimmy C]

Further looking suggests 6-3 cable if it has a ground will have a #10 AWG ground wire.

http://buyawg.thomasnet.com/viewitem...b-and-type-mc#

So this makes me wonder about your pump motor and Salt System controller. If both are 220V then the neutral current will be zero (desirable). Here there will be no voltage drop on the neutral wire because the load will all be on the 220V wires. This would eliminate any voltage between ground and neutral unless something else is wrong like a poor ground at the main panel.

I hope you are NOT using a 120V pump from one side hot to neutral. This creates unbalance resulting in voltage between ground and neutral. This would be even worse if the electrician used the 10 AWG wire as the neutral wire.

If you have voltage between different points around your pool, and you have a Salt system, expect for rapid galvanic corrosion to take place. Left unchecked that could cost you a fortune to fix.

Jim

[Jimmy C]

Must read:
http://www.poolforum.com/pf2/archive...hp/t-5460.html

[BigDave]

I read through the thread that JimmyC referenced and it made me think: Is your water bonded? Is there an electrical connection between the pool water and the bond? Maybe your light does it but maybe not.
You still need to verify that your meter pan neutral is grounded and that ground is strappped to neutral in the service entrance panel ( these are two different things).