In article ,
Mike P mike@askme wrote:
On Wed, 12 Dec 2007 10:26:59 +0000 (GMT), "Dave Plowman (News)"
wrote:

.. In article , .. Mike
P mike@askme wrote: .. The circuit cable is larger. It has 3 coiled
earth wires for a start. .. I spurred off with a 30amp junction box
using 2.5mm. .. Why should the cable all be the same size? .. ..
It sounds like you've got old cable called 7/0.29. snipped

What you describe, is what I have and it is pvc covered.

Should be ok for many a year yet, then.

I have no concern about the cooker feed as it has its own direct supply.

Eh? Is this a red herring? ;-)


To all
who feel concerned this is as far as I go with electrics. Though I did
move the central heating thermostat to another room.

This saga all arose because wifey got me a junction box from the HB
shed, as I did not have the time to go to the local trade leccy. For
some inexplicable reason I was reading the instructions that came with
it, as I swigged a cup of coffee. It stated that the spur cable should
be the same size as the circuit cable .. which made my 6m of 2.5
somewhat redundant ! Hence the questions.

All they're saying is that it should have the same current handling
capacity as the ring main cable - which means in effect the same type. In
your case you're simply using the modern equivalent. The reason for this
is it's not the power the socket may take - in your case only small if AV
stuff - but to maintain a suitably low earth conductor impedance so the
breaker will trip quickly in event of a fault in the wiring to the socket.

What may have confused many was saying you had a triple earth wire. What
you really meant was a stranded type which uses three strands twisted
together instead of the modern single strand variety.

--
*Most people have more than the average number of legs*

Dave Plowman London SW
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