[sdiy] My PSU...

[Tony Allgood]

> The Neutral is also bonded to the SAME earth point as the house earth.

But, I thought, perhaps wrongly, that neutral was connected to earth at
the local sub-station (11KV step-down transformer). And your house earth
was connected to earth at you house.

The voltage between the two can get very high depending on how much
current is taken by each phase on the substation's three phase outputs.
I would typically get it to be around 0V to 6V when I measured it.

Old (probably untrue) anecdote that is often banded around: One chap
used the PD between E and N to drive water up to a tank in his
greenhouse with a small pump. This is unmetered electricity and is
therefore 'free'. During the coldest part of the night, a little
thermostat would reverse the flow of the water and the electricity
generated would heat the greenhouse. The story goes that he was caught
by the electricity board and fined. I have heard similar stories from
different sources, so it has to be true :-)

Regards,

Tony Allgood                       Penrith, Cumbria, England

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