Schlepp, I asked you to explain how the guy was shocked. You did not do it.

Think, in other words, and explain the shock. Explain where the power came from, how it got to him, and how it got to ground. Draw yourself a schematic. I don't think you can. Telling me to think about a neutral is no answer.


Thanks. It make sense now.

That guy was probably shocked because the house was properly grounded to a cold water pipe.

This is what Schlepp is missing. A guy who gets shocked while he's in the shower is in contact with a cold water pipe and a drain. This has tiny percentages of zero to do with any neutral in the house unless the shower wall has an open junction box in it. Unlikely but possible. My son just uncovered a bathroom light fixture that switches the neutral to turn it on and off. Bad idea but doesn't influence his shower experiences. (The switch and all other lighting circuitry is not in the shower.)

On March 22, 2015 at 20:57, King of typos said...

And probably had galvanized pipes for the drain. Thus why he had a shocking experience in the shower. Still points to an improper ground, as the drain pipes should have been grounded with the cold/hot water pipes as well.

Two times now someone mentions galvanized pipes. Why? They don't conduct quite as well as copper, so an electrically hot pipe would be more of a problem if it were copper, but galvanized is being blamed for something. Somehow.

If the drain pipes were PVC or ABS or whatever they use now a days, the cold/hot water pipes that became electrically hot, wouldn't have affected him at all. Unless the water acted as the "ground". But even on a first floor house, that pipe has to go down a foot or two, to which point there won't be a continuos stream of water to reach the ground.

This is mostly valid. Distilled water doesn't conduct electricity, but water with minerals may. Water with soap may. And that drop of a foot or two will probably have electrical paths that come and go as the water flows down the pipe.

Copper pipe for the hot and cold and galvanized for the drain.

The hot and cold are more than likely bonded to ground. The galvanized drain is not. So where the drain pipe goes out of the house is far from the ground rod for the house. Thus a potential voltage difference.

To explain voltage in the ground with a different senairo. Picture a circuit going out to power a light pole for a house. It's a direct burial wire, so it's more acceptable to damage. The home owner is complaining that the light will some times dim, go out, come back on and dim again. Ok, so there must be a break that is making and losing contact. There's also snow on the ground. But about 13 feet from the light pole, there's a spot where there's no snow. Dig there and there is the break in the wire.

Question is, why was there no snow there? Because voltage was leaking into the ground and the ground basically became a "dirty" heated blanket.

KOT

My parent's garage was wired by a friend, who was an EE. The lawn care guys refused to plug anything into the outlet on the garage because they were shocked many times but I was never able to repeat the problem when I would go there. Turns out, the problem was caused by the way EE wired the three-way switch for the light for the end of the sidewalk, at the alley- he was switching the neutral and the metal J-box was mounted over aluminum siding. Flip the switches one way, it was fine and the other, ZZZZZZZZZZZZZZZZZ! I found this by closing the aluminum-framed jalousy window when I was barefoot and at that time, I understood EXACTLY why they didn't use that outlet. Never blew a breaker, either.

If nobody has ever had the same problem in that area, I would say it was caused by someone working their magic when they added/changed wiring in that house.

If schlepp had come up with an explanation for the guy's shock, I would not be saying this, but now I have to: with this post I rest my case.

Here we have two EEs trying to be rational. One won't use his extensive knowledge to show me how and where my explanation is wrong, by providing one of his own. The other one hooks up a switch in a completely dumb and incidentally possibly fatal manner.

schlepp, I'm not trying to wind you up. I'm trying to get you to explain in detail what is wrong with my explanation, which you totally reject.

Not disputing the "switching neutral" comments, but I would only mention 1) Sometimes a white gets used for a switch leg in a 3-way if no 14/3 has been run but is not the neutral; 2) Sometimes a back-fed circuit uses a white for a switch leg but again, is not the neutral.

Closer inspection may have proved neutral is indeed being switched, but all I am saying is that just because it is white does not guarantee it is a neutral.

I'm just baffled. A power line hits the ground. A guy gets a shock in his shower. A cable box burns up and starts a fire.

How is that in any way related to switching a neutral? Was the neutral in the shower?

We don't have enough info to determine what caused him to be shocked and the cook the cable box. All we can do is speculate.

That's why I always pound in a grounded near every rack lol

Ok then what is the proper way to ground a rack?

Do you agree with this link [Link: engineereducators.com]

This is all very shocking...

Middle Atlantic has a great Power Paper which covers the proper way to ground a rack. I've seen this posted here before, not new to most here.

[Link: middleatlantic.com]

I saw a video the other day with two blacks and a white in a 3 - way.

Thank you, forgot about their white papers.

So, you add a ground that could possibly cause ground loops, assuming the house' wiring already meets NEC? The rack is supposed to be grounded to the main ground point, not your own. It may work, but.....

Was one of them wearing a piece of tape, with a different color? That was probably the traveler.

At least, I think that's what they call the odd one.