Peter Chadwick wrote:
>
> In the US power distribution system, I understand that the neutral is
> connected
> to ground at the point of entry to the property's distribution board. Do the
> electricity company provide a ground wire in parallel with the neutral, or is
> the ground purely a local ground from a ground rod or similar?
The ground is local. At my house, it was just a poor connection to a water
pipe! I drove my own rod to improve it. As I understand it, the power company
also has a ground rod at the distribution transformer on the pole.
> Is their any fault detection on that ground connection so that a ruptured
> neutral won't lead to the return current being through that ground connection?
Not in my case.
> Are cables witha metallic sheath used in the US, with the sheath being the
> neutral? Here we have cables with 3 phase conductors and a metal sheath for
> neutral - and ruptured neutrals aren't unknown.
I don't know about underground wiring, but certainly not for the aerial type of
system.
73,
Vic, K2VCO
Fresno CA
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