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charles charles is offline
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Default Wylex plug-in breakers ("upgrade" for ancient fused CUs)

In article , ARW
wrote:
"Mike Tomlinson" wrote in message
...
En el artículo , charles
escribió:

I had to upgrade the 6A lighting breaker to 10A in our village hall
after 2 500w floodlights were added to the lighting circuit.


I was going to ask if the wiring is up to it, but on googling see that
1mm^2 is ok to 10A and 1.5mm^2 to 15A.



It's not quite that simple.


1mm is OK for 16A when clipped in free air and 1.5mm for 20A.


Surround that cable with insulation and you half the current carrying
capacity.


Now that is usually only a problem IF you are near full load or IF you
have very long cable runs so that the earth loop is too high to trip the
MCB in the event of a fault.


The second one is not very likely to occur on most properties. The first
one depends on the lights that are fitted. A couple of 500W halogens
could shove things over the limits


I don't have any old copies of the Regs to give me current capacities, but
our hall was wired in 3/.029. ISTR it was a bit more than 1.5mm

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from KT24 in Surrey, England