Dave wrote:
Has contacted me about the Ozzie practice of using mains sockets to
connect to wind generated 12 Volts as they are cheaper than the low
voltage ones. This could result in a 12 volt device being plugged into a
12 volt mains socket and getting a bit of a shock. I have tried to
explain the problem, but I am not an electrician. Would anyone care to
correct the following before I post to him please.

start quote.

We call that PME over here. It is basically the same as you describe,
but there can be a problem with it. Our power supplies are earthed at
the transformers that supply the 230 Volts, from the centre of the 3
phase supply and again at the house input, by strapping the earth and
neutral together. (There is no true cable to actual earth) It can happen
that if an earth link fails at the incoming supply to a house on the
same phase the neutral can rise to the supply voltage, by virtue of all
the properties connected to that phase.

End quote

Regards

Dave
There would appear to be no commonality between the two section of your
post.