This will now confuse everyone however if you don't understand it don't
bother trying to!
Indeed Ian some places are as you say fitted with PME, but this system
as you've already found has serious and dangerous limitations. If the
neutral becomes disconnected as you and I have already experienced then
the Earth circuit becomes lives, it is then perfectly possible for
multiple earth paths one of which could become you as you touch your
water pipe and your live but earthed electrical appliance and get that
nice wake me up shock. (Water pipes now have to be bonded as do gas
pipes to the electrical earth but I wouldn't rely on that to save you).
I have encountered this situation is quite dramatic ways, not just in a
house or 2 but in whole streets or villages where a neutral return on
the local distribution system goes Hr series dis, even to the extent
that so called experts are running round like headless chickens trying
to find the fault or more usually denying that it exists. It can be and
often is extremely baffling as the load varies and the volts drop across
the disconnection varies and the current distributes itself across the
multiple parallel paths.
For the average ham who introduces his own local earth for RF local
interference prevention or antenna purposes it is even more dangerous
since he could under the right set of circumstances have a whole
streets neutral current return flowing down his own local earth (FREE
Electric at last!)
In my own case I have disconnected the nice but dangerous PME provided
by the local supply company and installed my own local earth system
which is totally independent of theirs (AND TESTED TOO) both in the home
and shack. I have also installed a very sensitive and expensive current
operated earth leakage trip.
They might electrocute someone but it isn't going to be me.
The rule for Joe public still is do not use ground in Europe as a
return, use neutral instead!
Paul
In message <3A5257E5.429C953F@integritynet.com.au>, Ian C. Purdie VK2TIP
<ianpurdie@integritynet.com.au> writes
>
>paul wrote:
>
>> I know of nowhere in Europe that uses Ground as a return, certainly not
>> in the EEC, could you please identify this place. I would like to know
>> in case I should go there and electrocute myself with my UK electrical
>> appliances (which are CE approved - a European standard) and which use
>> NEUTRAL as the return and not ground.
>>
>> Ground is only used for a safety earth in Europe please note!
>
>I thought UK was the same as Australia and used the M.E.N. (multiple earth
>neutral) system.
>
>Here at every meter box the earth is tied back to the neutral link. In
>recent years the water service earth has been electrically insulated from
>the water mains in new installations for safety reasons and earth stakes
>employed.
>
>I have encountered many "live" earth systems in my life as a plumber. Take
>nothing for granted.
>
>http://www.electronics-tutorials.com/basics/earth-dangers.htm
>
>
>72/73's
>
>Ian Purdie
>"I believe Australia is the best address on earth"
>Budgewoi N.S.W. Australia - Co-ords S33°14', E151°34'
>My FREE Newsletter: http://www.electronics-tutorials.com/subscribe.htm
>VK2TIP "I'll give ya the TIP mate" QRP-L #1978. SOC #171 FP#91
>URL - http://www.electronics-tutorials.com/
>
>
>
>--
>FAQ on WWW: http://www.contesting.com/FAQ/amps
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>Problems: owner-amps@contesting.com
>
>
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