Wierd electrical question...

[Richard]

Yesterday I got to celebrate fathers day by going with the wife over to her fathers house and I got to replace not only the weatherstrip at the base of his shower door, but also his heating elements in his water heater.



We were clearing out a lot of calcium and re-filled tank again so we could "rinse" it. Upon putting it back together properly for the final time it wouldn't go so this 10 minute deal ended up taking 4 hours.

Here's where it got weird...

The insulation around the lower element was wet. Some water was also on the floor. I might add that I personally turned off the breakers so I knew the power was dead for the heater.

His new element was a bit thicker than the old so unbeknown to me, there was NO WAY it was going to screw back in (bolt in verses screw in element) Had I figured this out earlier, the entire thing would have taken 10 minutes and I wouldn't have fought this stupid thing for hours.

Ok, so I'm trying to put the bolts back in and I touch the wet insulation as well as the heating element itself (the outside as I push it in). I got a mild shock. Thinking at first it was my hand being sliced by sliding it along the metal open part, I didn't give much thought. Happened again and again.

(I was sitting on floor and towel in front of me was wet)

Long story short, it was MILDLY shocking me every time I touched it, unless I was standing (rubber shoes). Then of course, I could barely reach it and it killed my back to be stooped over.

I stopped & told my father in law to go kill the main breaker for the ENTIRE house. He did so and now the house is 100% dead.

I went back at it with 2 flashlights at my disposal and was STILL GETTING SHOCKED!

Called my brother in law (electrician) and he came over. Seems there was about 12 volts measuring here when he touched his probe from the wet insulation to the ground or maybe it was to the element...I don't really know what he was measuring, he just verified that in fact, there was some current there and we didn't know why since the main breaker was cut.

He finally speculated that perhaps the power company had an issue with their power lines and might have been sending power up a wrong leg (or something like that which is WAY above my head)

We had a lightning strike a week ago and it vaporized about 400' of the power companys neutral line. They replaced it 6 hours later. That's the only recent event that we know of.

Any speculation why you would have about 12 volts when touching a ground item when the main panel is turned off??

btw, I called the power company today to describe it to them. They were evidently interested in what I had to say & said he'd have someone check out their towers near us.

 

[biggerten]

OK.

There should be a ground wire to the water heater. This shoud be green or bare and terminate to a screw on the water heater chassis. This is besides the two 'hot' wires which carry the current (probably a black and a red, maybe a black and a white, but the white should be marked with black tape or something to show that it's 'hot'). I am assuming it's 220V.

This bare or green wire should be terminated at the other end in the box to the ground bus, which should then be grounded to at least one ground rod driven into the earth. It is also common to tie this ground bus to the cold water plumbing (metal pipe, obviously).

Something's wrong there, I don't know what, but it's a grounding issue. Your BIL should be able to figure it out, being a licensed electrician. There cannot be a potential between the water heater chassis and ground if things are wired correctly.

Power up the wrong leg? Puhleeze. It would be like the Fourth of July, televisions popping, refrigerator motors blowing. The problem is in the house wiring.

 

[Richard]

The problem is in the house wiring.

This is what I thought initially...but lemme ask... if so, then how is it possible that I was still feeling a shock when the main breaker on the panel box was turned off?

Shouldn't that kill 100% of any issue inside the house, regardless of what might be wired or grounded wrong?

Electricity and house wiring is certainly not my area of expertise so I don't presume to know anything here but I would think killing the main breaker should have made working on this foolproof yet, it was clearly "sharing" its voltage with me as I touched it.

 

[tommu56]

I'd check the ground and neutral connections at meter socket and panel.
Measure voltage from them to a new ground point to see if they are floating.

I'll almost bet that neutral has voltage on it Coming back from power co.
your ground / neutral bond might not have a good enough connection at the panel or meter to dissipate it. and if it is explain to them they need to fix problem before some one gets hurt.

tom

 

[SPIKER]

like TOMME said, there is an induced voltage between the N line/Ground line and the HOUSE WATER LINE more than likely, if this is a WELL then there is chance that the WELL has best ground in the area and this Neutral voltage is being bled back through the drop and into the house. Not knowing what kind of wiring you have to the water line and the main junction box and incoming water line it is hard to know what/where the problem lies...

Mark

 

[Uncle Doug]

Sounds like a floating neutral to me. It may be sharing a neutral with another circuit and getting a backfeed through the neutral. Grounding the unit should fix the problem. If not you may have to open the junction box where the splices are to see if the neutrals are shared or swapped.

 

[Inspector507]

Disconnect any cable TV and telephone lines including any ground connections to the same. Then turn the main off and test it again. I worked on one house that had 8-12V on the metal siding. Turned out it was a bad cable TV ground.

 

[Richard]

Disconnect any cable TV and telephone lines including any ground connections to the same. Then turn the main off and test it again. I worked on one house that had 8-12V on the metal siding. Turned out it was a bad cable TV ground.

I'll advise them (bro in law) on that comment...question though, father in law is on satellite, would that rule that out? (Direct TV)

the phone should be piece of cake to cut...

?

 

[Inspector507]

I'll advise them (bro in law) on that comment...question though, father in law is on satellite, would that rule that out? (Direct TV)

the phone should be piece of cake to cut...

?

The satellite dish should cause a problem.

 

[Scooby074]

Toms got it. Killing you main only disconnects your feed. THe neutral is still connected. You likely have some grounding issues as well. could be corrosion or ground conditions. Thats my bet.

 

[tommu56]

I didn't think of it but I have seen a breaker that went through a flood that would open but the dirt in it would keep a couple of volts on the line.

I recommend every one have a non contact voltage tester

like the Fluke 1AC A1 II

http://us.fluke.com/usen/products/Fluke+1ACII+VoltAlert.htm?catalog_name=FlukeUnitedStates&category=ELT(FlukeProducts)


and test it on a known live line before use.

tom

 

[biggerten]

This is what I thought initially...but lemme ask... if so, then how is it possible that I was still feeling a shock when the main breaker on the panel box was turned off?

Shouldn't that kill 100% of any issue inside the house, regardless of what might be wired or grounded wrong?

Electricity and house wiring is certainly not my area of expertise so I don't presume to know anything here but I would think killing the main breaker should have made working on this foolproof yet, it was clearly "sharing" its voltage with me as I touched it.

Who can say what the real problem is? But for sure you haven't located it. You really need to check that the ground is in place at the heater, that the other end is connected in the panel, and that the panel is grounded. The situation is suspicious enough that there are probably multiple issues here, and that another circuit or a faulty device is energizing what you *think* is ground, but really isn't. Another poster mentioned phone lines, an intersting possibility.

But the voltage is coming from somewhere, and your grounding circuit is deficient somewhere.

 

[dmccarty]

The satellite dish should cause a problem.

My Sat dish does not have power running too it. How would power come from the Sat dish? COAX does run to the dish is that somehow powered? Course if it was powered then when Richard drops the main it should not be powered.

Or does the dish pick up the 12v from the signal?

More Confused Than Usual.
Dan

 

[kenstrac]

Are you the only one on the transformer?
Is the entrance cable damaged and causing leakage?
Ground at pole bad transformer lost grd.
Pull meter and check all the connections for corrosion causing leakage.
How close are you to another service or neighbor?
Shut off all of the breakers see if it goes away could be back leakage from defective UPS

 

[Lil_FarmerJim]

My Sat dish does not have power running too it. How would power come from the Sat dish? COAX does run to the dish is that somehow powered? Course if it was powered then when Richard drops the main it should not be powered.

Or does the dish pick up the 12v from the signal?

More Confused Than Usual.
Dan

Not to speak for the Inspector, but I think that was a typo


And just to add to the discussion, in the US we have a combined bonded ground and neutral which is different than Europe. So if you loose the ground in your house that means any voltage coming back across the neutral line to the house will not be sent to ground and zero'd out.

So what you should do to eliminate your house as the source of the problem, bad ground or neutral issues. Have you BIL or another qualified electrician pull the house meter and check for potentials there. Since that is the entry point into your house you can inspect your grounding at the entry point as well as tell exactly what you are getting from the power company. 9 times out of 10 your issue will be yours and located in the meter box. Failed bond or broken line is the normal cause.

I can't stress this enough, unless you are a qualified professional electrician, pulling the meter should only be done by a professional. This is not a DIY test as you can and will kill yourself if you accidentally touch the wrong lines and ground yourself. There is no breaker to pop between you and the pole. Just you.

 

[biggerten]

Your satellite dish *does* have power running to it, there's an amplifier at the dish. The power is run through the coax cable.

 

[tommu56]

Not to speak for the Inspector, but I think that was a typo


And just to add to the discussion, in the US we have a combined bonded ground and neutral which is different than Europe. So if you loose the ground in your house that means any voltage coming back across the neutral line to the house will not be sent to ground and zero'd out.

So what you should do to eliminate your house as the source of the problem, bad ground or neutral issues. Have you BIL or another qualified electrician pull the house meter and check for potentials there. Since that is the entry point into your house you can inspect your grounding at the entry point as well as tell exactly what you are getting from the power company. 9 times out of 10 your issue will be yours and located in the meter box. Failed bond or broken line is the normal cause.

I can't stress this enough, unless you are a qualified professional electrician, pulling the meter should only be done by a professional. This is not a DIY test as you can and will kill yourself if you accidentally touch the wrong lines and ground yourself. There is no breaker to pop between you and the pole. Just you.

Note pulling the meter will not isolate the neutral from the neutral wire coming in to the house . it will only brake the line wires coming in (this might be a reagonal thing) but if you still have voltage after the mete ris pulled it has to be coming back from the utility.

tom

 

[jwstewar]

Your satellite dish *does* have power running to it, there's an amplifier at the dish. The power is run through the coax cable.

But not if the mains to the house are disconnected.

 

[zzvyb6]

This same thing happened at my place. Turns out that with the lowered water table and dry soil, the copper rod "ground" was no longer grounded to planet Earth. Drove a new rod and the differential voltage went away. Also, the Aluminum wire they used for ground cable turn to sawdust when we touched it. The tip off was that the Ground Fault Interuptors were going haywire until a rainstorm passed thru....

 

[biggerten]

But not if the mains to the house are disconnected.

I think your mixing up messages from the original poster, Richard, who opened the circuit breaker, with Dan, the one I was replying to, who said nothing about removing power.

Otherwise, I agree 100% with you, if there is no power is supplied, there will be no power in the circuit. But that's kinda like saying water is wet, we all know that.