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Re: Presumed RF Interference
Ian Mason wrote:
I think it is also important to note that NEC 250.52(B) prohibits gas piping as a grounding electrode(1990 or so). The gas pipe ceased as a grounding electrode due to the dielectric fitting at the meter. The gas company did not want a bond around the meter because it defeated the isolation fitting.On 6 Mar 2006, at 15:06, [email protected] wrote:The purpose here is not to use the piping *as* a ground, but to ensure that the piping *is* at ground potential. Otherwise, if an electrical failure causes the pipe to reach a dangerous potential then so does the water in it, then so do the hands you're washing in that water. Thus if there's an electrical discontinuity in the piping it is even more important to earth bond any conductive piping/taps etc. that are on the non-earth side of that discontinuity. The same applies too to gas piping except here the principal risk is static, sparks and the subsequent explosion.On Mon, Mar 06, 2006 at 09:49:39AM -0500, Steven M. Bellovin wrote:On Mon, 06 Mar 2006 21:17:17 +1100 Matthew Sullivan <[email protected]> wrote:(In the
The presence of gas is not relevant, IIRC.
In the old days, it was a big no no (at least according to the hourly wage fellows who actually do the work) to hook the gas line "as" ground other than any incidental grounding which ocurs in a gas furnace as an example.
Good place for resources is http://www.mikeholt.com in the forums. Decent community of knowledgeable folk there.
Good luck, and "no" do not use your body/fingers/arms/etc to connect various pieces of equipment to see if a voltage exists:-) That's best left to close friends who stand near electric fences.
I had problems in the mid 1990's in an older home where the galvanized water supply pipe was the primary ground. Over time, corrosion of the pipe reduced conductivity, and lightening storms toasted a few expensive items (e.g. ISDN gear, sun workstation, etc) before finally driving a few grounding bars into the soil in the basement.