Please forgive the homeowner-type question. I'm a VDV installer, and I've already asked the pro electrician in the family:
My house was built in 2000, with a 200amp lateral-fed service. There is a stranded aluminum GEC running to the area where the water service enters the basement and a #6 copper running out to a buried rod.
That's reasonable. But wait. The water service is via plastic pipe and there is a compression fitting transition to copper 2 inches upstream of the ground clamp for the GEC. There's no way an electrician could miss the pipe being plastic.
I asked the family pro (industrial and motor control, high-volt, etc) about this. His answer was that "You're grounding to the water system, not the pipe, so it's fine".
I'm confused. I seems to be a violation of the NEC as I read it, and I was under the impression that water was not a particlarly good conductor, as compared to metal and earth. Can anyone explain the rationale behind this installation?
