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Posted By: wendel 3/4" Copper Pipe Driven 8' as Ground Rod? - 01/17/06 06:31 PM
Rather than a copper-clad steel rod, is it acceptable to use an 8 foot piece of 3/4" copper pipe (driven into the ground) as a ground rod? Is there a requirement that the grounding rod be solid or is that to make it easier to hammer it into the ground?
Thats a good question I would say yes because it would be the same as using the water supply as a GE. but some one will probably prove me wrong.
Posted By: Geno Re: 3/4" Copper Pipe Driven 8' as Ground Rod? - 01/17/06 06:44 PM
It would probably have to be listed for the purpose
see what did i tell you. lol
geno, makes a good point. it would have to be listed for that purpose.

[This message has been edited by Wizzie Electric (edited 01-17-2006).]
Two words: "Not listed". However......

Stick an old gate valve and solder a copper 90 on to the end of it so that it technically becomes part of the water supply system and VIOLA, its acceptable.

See we all thought plumbers were out there to make life difficult, and as it turns out [Linked Image]
Look at 250.52(A)(5). There is no requirement that a pipe used as a grounding electrode be a listed product.
Don
Posted By: wendel Re: 3/4" Copper Pipe Driven 8' as Ground Rod? - 01/17/06 09:21 PM
The only physical requirement for a copper ground rod I can think of is that the volume of copper per inch in the grounding electrode be equal to or greater than the volume of copper per inch in the connecting/bonding wire. Otherwise a surge current could generate enough heat to melt the electrode while the connecting wire was still intact. Unlikely, but we're talking hypothetical extremes to help understand the right way to do things.
I would be worried about corrosion as the intent of the copper pipe was not to be buried.
If youre going to pretend it's plumbing (by nailing an old gate valve on top), it needs:-
a] to be at least 10 feet long.
b] an additional earth driven rod too!- see 250.53(D)(2)

Alan
wendel,
Quote
The only physical requirement for a copper ground rod I can think of is that the volume of copper per inch in the grounding electrode be equal to or greater than the volume of copper per inch in the connecting/bonding wire.
The code does not contain any such requirement. 250.52(A)(5) permits the use of any metal pipe at least 8' long and with a minimum size of 3/4" to be used as a grounding electrode.
Don
Don, I think there's the rub...code says "pipe", not tubing. I don't think regular copper water TUBE would be ant more acceptable than EMT.
Posted By: e57 Re: 3/4" Copper Pipe Driven 8' as Ground Rod? - 01/18/06 03:14 AM
Quote
(5) Rod and Pipe Electrodes. Rod and pipe electrodes shall not be less than 2.5 m (8 ft) in length and shall consist of the following materials.
(a) Electrodes of pipe or conduit shall not be smaller than metric designator 21 (trade size 3/4) and, where of iron or steel, shall have the outer surface galvanized or otherwise metal-coated for corrosion protection.
(b) Electrodes of rods of iron or steel shall be at least 15.87 mm (5/8 in.) in diameter. Stainless steel rods less than 16 mm (5/8 in.) in diameter, nonferrous rods, or their equivalent shall be listed and shall not be less than 13 mm (1/2 in.) in diameter.

Electrodes of pipe or conduit, (I have never done one...) that portion of the cod does not say it need to be listed, or have water in it.
But if a steel or nonferrous rod, it does.
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