"Bud--" wrote in message
...
Jimmie D wrote:
"Thomas Horne" wrote in message
k.net...

And my point is that your opinion does not jibe with the National
Electric Code.
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Tom Horne


Please Tom, tell me in what way that the grounding system should be
sufficent on its own and not having to rely on the plumbing to provide
grounding for an electrical system in violation of the NEC.

In violation of the NEC?? Underground metal water pipe was a required
electrode in the oldest NEC I have, 1968, and I think it has been required
since shortly after Columbus ‘discovered America’.


Also please tell me how you intend to prevent the scenario I discribed
where the ground system was completely disconnected from the home when
the well's metal plumbing was replaced with plastic.

My point exactly, and who is going to replace the pipe, definately not an
electrician that will make sure the ground system is maintained.


For that very reason the NEC requires a “supplemental” electrode. As the
“NEC Handbook” makes clear, the supplemental electrode is not required
because metal water pipe is a bad electrode, only because it may be
replaced in the future by plastic.

The supplemental electrode was commonly one or two ground rods. Rods are a
little better than nothing - a rod-to-earth resistance of 25 ohms is
considered acceptable, or install 2 and resistance doesn’t matter. With a
supplemental rod, if an underground metal water pipe is replaced with
plastic a good grounding electrode system becomes a poor system.

The 2005 NEC generally requires adding a “concrete encased electrode” in
new construction . This is actually a decent electrode.



The Code is the min and max that an inspector can apply to an inspection
This means that the inspector cant find fault with using plumbing for
grounding if this is what the code says, it doesnt mean that the
inspector can find fault if it is built better than code requirements,
so again I say the code is written to a minimum spec. Your own
definition of min max confirms this. Traditionally the NEC has the lowest
minimum standard and the state and local codes usually have a higher
standard., there may be some exceptions to this. I will will stipulate
that using plumbing for ground may be "to code" in some places but it
still is not a good way to ground your house and definately should not be
used for a lightning ground.


Using underground metal water pipes for grounding is “to code” anywhere
the NEC is adopted and not modified. That is a major piece of the US. The
requirement to use metal water pipe as an electrode dates back a long time
and is substantially unchanged. The authors of the NEC see metal
underground water pipe as an effective grounding electrode. As Thomas
said, “your opinion does not jibe with the National Electric Code”. You
also don’t say what your improvement over water pipe is.

If installing lightning rods a different NFPA standard is used. If
installing a lightning rod in the form of a tower or high antenna it would
also be wise to look at other standards.



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Regarding corrosion, water pipe corrosion has been investigated by the
International Association of Electrical Inspectors and the National
Institute of Standards and Technology, and corrosion problems were found
to be minimal.

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bud--