According to Jeff Wisnia :
wrote:
It should be less than the utility neutral but beyond that it is
unpredictable without knowing what is on the utility side of the water
line. If this is all metal pipe, the ground electrode system might be
as good a conductor as a perfect neutral wire. Bear in mind the
utility grounds their side of the XO terminal of the transformer too.
This makes the piping system a parallel path and there is nothing you
can do about it. Just be sure you have a good amount of current on the
neutral and that the phases have equal voltage referenced to neutral.
At last, someone who understands parallel current paths and agrees with me.
It ain't necessarily so that the the OP MUST have hot to neutral leakage
somewhere in his home's electrical system.
Consider this, then, while this conductor is indeed in parallel
with the neutral to a certain extent, it's pretty much relying on
the conductance of the dirt to move that 6A, at what's probably
a pretty low neutral-ground voltage. Dirt generally isn't anywhere
near as conductive as a copper wire. So a simple parallel current that
high seems extremely unlikely.
Furthermore, that amount of current is bound to greatly accelerate
any galvanic corrosion (eg: of the pipe).
It needs more investigation. I'd have it looked at. Experiment
with flipping off the main breaker and individual ones.
--
Chris Lewis, Una confibula non set est
It's not just anyone who gets a Starship Cruiser class named after them.