Shocking Shower

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Thanks for the good advice. I've seen the tube things with two handles for inserting fence posts. I'll put out the word I'm wanting one for a couple days.
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Christopher A. Young
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The furnace was originally installed so they would not have to drain the pipes in the winter. We do zero F now and again, and pipes do freeze.
From what I could see, the furnace guys did fine. I think it's the electrician who made the run of wire to the shower building that didn't put in adequate neutral / ground.
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Christopher A. Young
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On Mon, 11 Jun 2007 21:06:16 -0400, "Stormin Mormon"

I'd call him then, and say the same sort of thing. So that he wants to come out at no charge and fix the mess he left. You're not using the furnace now so he's bound to be nearby sometime in the next month, and it will take him 10 minutes.
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Through the air. AC at 60hz acts like a radio wave in that it can induce a voltage in a conductor near by. Any wiring, motor or transformer will radiate electromagnetic radio waves. The plumbing is the antenna that is being induced.

The felt voltage is not coming directly from the wiring.
The shower head is the hot lead of the voltage source and the wet ground or drain is the other conductor. Electricity has to have a path to be felt.

Short the two leads. The shower head and the floor drain.
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On Jun 11, 4:30 pm, snipped-for-privacy@mucks.net wrote:

Yes, and of the billions of homes, office, business, etc buildings, this one is the only one where this induced AC electromagnetic effect through the air is occuring. And it's coming through the air from the furnace to the bathroom shower? LOL
This is definitely a grounding problem of some kind. We don't even know what the grounding arrangement is, whether it was done correctly, or whether some grounding path has been interrupted. That's where I'd be looking, not at EMI.

Yes, and of the billions of homes and businesses buildings, this one is the only one where this induced AC electromagnetic effect is occuring.
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On Tue, 12 Jun 2007 05:43:45 -0700, snipped-for-privacy@optonline.net wrote:

It depends.
If the exposed shower plumbing is large and not grounded properly.
If a person gets wet and increases their contact surface area and thus their conductivity.

It definitely can be. The OP said that people can feel an electrical charge. He didn't say that the charge knocked them down. Seeing how these wet people standing on the wet ground are great conductors it can easily be a induced voltage on the plumbing caused by a near by transformer or motor.

You'd be surprised what voltage is induced on different conductors. 'Normally you would never notice. This one is different because showering people can conduct much more easily. Grounding such systems properly becomes much more important.
The easy fix is to ground the shower plumbing to the floor/ground/drain.
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Are the ground and the neutral separated in the new subpanel or are they bonded together? Do you have a good grounding conductor from the subpanel to the main panel? Is there a good ground at the main panel? By good ground I am referring to two ground rods and a connection to the main water line.
Any chance of getting some pictures of everything?
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: : : : Are the ground and the neutral separated in the new subpanel or are they : bonded together?
CY: The grounds and neutrals go to different bars. Beyond that I don't know.
Do you have a good grounding conductor from the subpanel : to the main panel?
CY: There is a conductor. But the fellow who runs the camp didn't seem at all pleased with the electrician. So, it may not be good.
Is there a good ground at the main panel? By good : ground I am referring to two ground rods and a connection to the main water : line.
CY: The panel in the shower building has no signs of ground. The wire goes out to a cement box, which sits maybe 6 feet from the building. I see no connection from the panel to the water line.
: : Any chance of getting some pictures of everything? :
CY: That is a very wise question. I don't have a digital camera, but been considering getting one.
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I'm thinking that you need to get an experienced electrician to look over the electrical system. There is obviously a hazard to human life. This is not a situation for a do-it-yourselfer to play around with. You need to make things right and soon! Get a professional electrician now! What ever the cost it is still cheaper than a human life.
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John Grabowski wrote:

The neutral bar should be insulated from the box. It is possible there is a bonding jumper from the neutral bar to the box. Sometimes a very visible strap. Sometimes a very non-obvious screw - usually green.

Not obvious if you are saying there is no grounding electrode at the shower building. It is code required. Rods are notoriously poor, but the easiest if an electrode is not now present. Code is 8' (as someone said) and 2 are usually installed.
A slight possibility - if you have no grounding electrode and have a neutral-ground bond in the panel, the shower ground wires would lift from earth potential. Adding a furnace could provide a path from the shower ground wires to the shower valve.
Earth potential is not as fixed as is commonly assumed either, though a remote church camp one wouldn't expect much variation.
Around swimming pools (and buildings for animals on farms) the floor and accessible metal are all bonded. The equivalent would be connecting to the reinforcing mesh in the concrete floor when constructed and bonding to the valve, shower head, ...
Bond everything and make sure you have a connection to the earth at the remote shower (as someone else said).
Also not established - separate shower buildings for girls and boys? Could explain why girls get shocks, not boys. As a temporary fix you could have the girls shower with the boys.

A competent electrician sounds like a real good idea.
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And that could do it, too -- leaving that screw in, I mean, when it should have been removed. [...]

Actually, Code is 8' or to the depth of permanent soil moisture, whichever is deeper. [Article 250.53(A)]

True, but not by itself sufficient to cause the observed problem. Apparently the water pipes in the shower building are not properly grounded either. Code requires metal water piping to be bonded to the electrical grounding system, to ensure that there won't be any potential difference between the water pipes and ground.
[...]

Even more shocking. <g>
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Regards,
Doug Miller (alphageek at milmac dot com)
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Doug Miller wrote:

250.53-A is installation and is not whichever. 250.52-A-5 has requirements for the electrode - min 8'.
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250.53(A): "Where practicable, rod, pipe, and plate electrodes shall be embedded below permanent moisture level."

Note the word "minimum". Clearly, if the depth of permanent moisture is at, say, 10 feet, and it is "practicable" to drive a rod to that depth, 250.53(A) *requires* doing so.
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Doug Miller wrote:

I misread your original post as 8' or moisture whichever is less. What you wrote, whichever is greater, is right and is a good practice.
I doubt you usually know the depth to permanent soil moisture, which makes the article a little hard to enforce. And I doubt it is enforced. Fortunately the move is, in general, to Ufer/concrete encased electrodes, which are far better electrodes.
Anyone been required to use a ground rod more than 8' in the earth?
-- bud--
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Went back to the summer camp. Just simply can't get the shower to shock. Yes, took off a shoe and sock, and put the wet foot on the metal drain. Tried everything we could think of, and can't get the shower to shock.
Turned on lights. Turn on furnace. Try a different shower.
Traced some wires. The ground is NOT tied to the neutrals. The ground wire goes to a stake in the ground. The neutral goes back to wherever neutrals go.
They are going to call in an electrician. In the meantime, we unhooked the furnace in case that's the source of power. I suspect a bad neutral. When they have a lot of lights, etc, going in the cabins, the neutral might be higher than ground potential. How that's getting into the shower pipes is still unclear.
I'll keep you posted.
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Christopher A. Young
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Stormin Mormon wrote:

Another possibility is 'mass hysteria'. One person thinks they feel a shock and others, who then have an expectation, can 'feel' one.

Thanks. It will be interesting.
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Bud-- wrote:

...
True, and except for the fact he actually was able to measure a potential difference and (iirc) feel it himself initially, I'd think it a higher probability...
But, again, since it's a public facility, caution is the word of the day...
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On Wed, 13 Jun 2007 19:44:55 -0400, Stormin Mormon wrote:

Well I am no electrician but I know a few and am an electrical engineer. The neutral seperation from the ground does not sound right to me. The ground and neutral should be at the same potential except when there is current flowing through the neutral. The fact that they are disconnected seems wrong.
Of course I guess proper terms are in order. when you say 'ground' what do you mean? The wire connected to the 3rd prong in outlets and whatnot? That is the onlything I think you can call a ground. that should go back to the panel and tie into the neutral, then from there they both should hit a stake in the ground together. So they will always be at same potential. IIRC.
With that current layout, if that stake in the ground becomes a better return than the proper neutral for whatever reason, you will be shocking people. This can change based on earth conditions and maybe even neutral loading.
Im not electrician but it does not seem proper.
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Stormin Mormon wrote:

This is an interesting thread, although I don't know more than the very basics of what is being discussed....but.....I can understand consulting other DIYers if the writer was the only person being affected. So, a bunch of campers are getting mild electrical shocks and you are diddling about what to do or not to do? You have to be nuts! If there is any possibility that there is a loose or crossed connection that could vibrate or expand and make full contact, then what? Save $200 and electrocute a kid? I will send $10 to the OP to help cover the cost of a licensed electrician.
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I'm the OP. The building was wired by a licensed electrician, and the furnace was installed by a business. So, anything I do has to be better than that.
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Christopher A. Young
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