W_Tom is a long time, and well documented usenet freak troll. His bag is to post
lengthy diatribes that contain enough true technical facts to sound legit, but
then he goes over the edge and adds fantasy crap. Don't ever trust ANYTHING he
posts. He's got a history of this that goes back for years. He's a very clever
troll, but he's nonetheless a TROLL. He has posted advice that could easily KILL
somebody. That's how he gets his jollys.
There is a length of copper pipe between the plastic supply pipe and
the meter. It is about a foot long and holds the shutoff valve. There
also is a length of copper pipe from the meter to the connection with
the internal PEX. It is about 3 ft long and has a tap on it.
Paul et. al.
That simply is not true. The US National Electric Code requires that
underground metal water piping that is ten or more feet in length must
be used a grounding electrode. It also requires that the any interior
metal water piping be bonded to the grounded conductor of the electrical
"250.50 Grounding Electrode System.
If available on the premises at each building or structure served, each
item in 250.52(A)(1) through (A)(6) shall be bonded together to form the
grounding electrode system. Where none of these electrodes are
available, one or more of the electrodes specified in 250.52(A)(4)
through (A)(7) shall be installed and used.
250.52 Grounding Electrodes.
(A) Electrodes Permitted for Grounding.
(1) Metal Underground Water Pipe. A metal underground water pipe in
direct contact with the earth for 3.0 m (10 ft) or more (including any
metal well casing effectively bonded to the pipe) and electrically
continuous (or made electrically continuous by bonding around insulating
joints or insulating pipe) to the points of connection of the grounding
electrode conductor and the bonding conductors. Interior metal water
piping located more than 1.52 m (5 ft) from the point of entrance to the
building shall not be used as a part of the grounding electrode system
or as a conductor to interconnect electrodes that are part of the
grounding electrode system." Copyright 2002 National Fire Protection
"This alternating current stuff is just a fad. It is much too dangerous
for general use." Thomas Alva Edison
Water pipe alone is no longer sufficient as the earth ground
electrode. Water pipe (meeting additional criteria) can be
part of a "grounding electrode system"; but is no longer
sufficient AS the earth ground. Meanwhile, safety ground must
bond to the water pipe to remove electricity from that pipe.
Obviously, that safety ground would also become part of the
earthing system. But that water pipe alone is no longer
sufficient as the earth ground.
In the 2005 NEC this is 250.53. This is a "supplemental electrode". The
water pipe is a great ground and is the grounding electode. The problem
is it could be replaced by plastic in the future. Supplementary
electrodes are protection against that possibility. Ground rod(s), which
are commonly used as the supplemental ground, are not particularly good
grounds. (A 25 ohm ground resistance is pretty funny.)
I have no idea what "removing electricity from the pipe" means.
I have not seen anything like that, I live in Columbus, but I guess it
is possible. I do suggest that you don't rely on plumbing for a good
reliable ground in any home. If you need a true ground, put one in.
Assuming you get your electricity from a utility, there already is a "true"
ground at the service entrace for power. The "network protector" of the
telephone company is also connected to that ground.
If you have metal plumbing inside your home, it probably a good idea to bond
that to your electrical utility ground.
Some of this stuff goes back to the old days when the water distribution
system was metal and there just wan't any better ground than a water pipe.
A tradesman might just automatically connect the meter jumper just because
it is quicker to install a jumper than try to explain why a jumper isn't
A similar thing happened with the electric utility ground system. The rule
was that you only needed one ground rod is you could show that the
resistance to ground was less than 25 ohms. Otherwise you needed two rods.
It was quicker to put in two rods than test the first rod.
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