Hi Olin,

> Almost the same here in the US, at least for individual houses.  There
> is
> a transformer near your house that is fed from one of the three power
> phases.  The secondary is center tapped with each half creating 110V
> AC.
> The center is grounded usually right where the power enters the house.
>  In
> my case there is a large copper rod driven into the ground right by the
> breaker box.  Half the circuits in the house are between one end and
> the
> center tap (neutral) and the other half between the other end and the
> center tap.  Special 220V circuits like for dryers and electric ranges
> are
> accross both ends of the transformer secondary.  Three wires are run
> for
> each 110V outlet, hot, neutral, and ground.  The neutral and ground are
> eventually connected back to the ground point, but the return currents
> are
> all intended for the neutral and ground is for safety.  "Ground fault"
> circuit breakers check for current in the ground line and trip if more
> than a few mA are found.

Yeah, That's pretty much how we have always done it. Except we have no
need for the transformers - since our 3 phases are 415V each, we tap in
at 240VAC

Residual Current Circuit Breakers or Ground Fault Breakers that trip at
30mA are pretty much standard now.

So you guys finally caught up? :-)

Cheers,

Sean

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