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.
--
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.

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.

--
bud--