What is "at a structure"?

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George Stolz

George Stolz

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Suppose there is a well casing composed of a metal pipe a distance away from the foundation of a house.

How close must an electrode be to be considered "at a structure"? If something fitting the description given in 250.52(A)(5) exists near a structure it must be used, same as any other type of electrode.

If you were to write a proposal to create a boundary, what would it be? Five feet? Ten? Fifty? The property line?

What would some of the implications be to creating, say, a twenty foot boundary for electrodes required to be included?
 
Perhaps for a limit proposal, you might use some guidelines that are generally kept in mind for agricultural equipotential planes. Something like the pace of the average man, or the height of the average man from the soles of the feet to the tips of the fingers on the upstretched arms. Something around 7 or 8 feet sounds conservative to me.
 
iwire said:
?

Why not Cubits?
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You could use that, but since the code is metric now, I'm not sure how to express that. I was giving what I felt the developed measurement should be derived from, based on limiting differences in potential due to how far a man could possibly reach and touch two places.

Bored today, Bob? Yeah, me too.
 
George
Is one of your horses like Wilbur from Mr. Ed??? :cool:
Is this horse asking you these questions? :wink:

where and when do you have the time to think of these things???

Like Bob said, it is a good question... just no real answer. Remember attorneys do not ask a question, unless they think they know the answer.
 
I didn't start this for an argument (probably a first ;) ), I was just pondering what the unintended consequences would be for such a rule, if one existed.

Tom, if you wanted to eliminate the water pipe electrode from a structure to get rid of the parallel neutral path, would you have to take extra pains to be rid of it, since the pipe would be within 10' of the structure? Would you be allowed to just install a non-metallic coupling at the foundation in that event?

Bob, "Cubits" about cost me a medical bill. :D

Pierre, I'll think up anything to get out of last-minute Christmas shopping. I really need to go.
 
Medical bill paid, two chickens and a bag of sugar.

What if you had a 10' or so mark and it was across the property line? do you just go connect to the nieghbors pipes or house "structure" ? and if he doesnt like that then what? He may want his chicken back. it could be a "potential" problem.......................:roll:
 
acrwc10 said:
What if you had a 10' or so mark and it was across the property line? do you just go connect to the nieghbors pipes or house "structure" ? and if he doesnt like that then what?
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Legally speaking, I think that would take care of itself, wouldn't it? Homeowner "A" would have to get an easement to get access to Homeowner "B"s grounding electrodes. Therefore, it wouldn't happen, and if it did, then the easement would protect access, so it wouldn't matter, would it?

At the end of the day, the NEC is a lawbook, to be adopted and nestled in amongst the other laws of the jurisdiction... ;)
 
mdshunk said:
Perhaps for a limit proposal, you might use some guidelines that are generally kept in mind for agricultural equipotential planes. Something like the pace of the average man, or the height of the average man from the soles of the feet to the tips of the fingers on the upstretched arms. Something around 7 or 8 feet sounds conservative to me.
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Maybe you might want to stretch this out to the average length of a Holstein from nose to hind legs. They are longer and would be most affected in this situation.
 
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