As a UK resident who has occassionally meddled wih electrics...
Our power is not 2x120 volt - we get a single phase 240 volt which is part
of the full three phase generated and transmitted. (our three phase is 415
volt). The neutral connection is added quite locally, I believe at the final
step down transformer. Putting an oscilloscope on my domestic supply (one
channel from earth to netural and the other from earth to live) shows the
neutral to be very close to zero volts - sometimes going up to 2.5 volts -
and in phase with my live. So, the neutral is pretty much at ground
potential, not a 'hot' wire. And my ground is just that, I have a 4 foot
copper pole driven in the ground.
We also don't have two pin plugs - except for shaver sockets - all outlets
are three pin. Ground connections have to be run to all outlets, all
switches, and all light fittings - even if the light socket does not pick up
the earth.
Neil
----- Original Message -----
From: "Ron Schmittou" <rs1121@earthlink.net>
To: <shop-talk@autox.team.net>
Sent: Friday, April 29, 2005 7:49 PM
Subject: RE: quickie elect. question
>
> I have never really understood the mania on this third wire or "Ground"
wire
> in the US since 99.9% of all electrical panels have the supposedly
"Neutral"
> wire and the "ground" wire connect to the same buss. In the UK where all
> the two wire plugs are actually both hot (two phases of 120) 220 volt - it
> makes good since to have a separate ground wire - but in the US each
outlet
> already has a ground wire, I don't see the reason you need two - It's even
> sillier now on the 220 appliances because you now have to have 4 wires
> instead of three - 2, 120 wires and 1 ground and now lets add another
ground
> wire.
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