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Rob Morley
 
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In article , "Alan"
says...

"xavier" wrote in message
m...
Stefek Zaba wrote in message

...
xavier wrote:
7KW Shower, 10m cable run. Is 6mm2 OK Please? No tables here, only

chairs

Xav

Definitely maybe ;-)

7kW is 30A at 240V (well, 29.2). The OSG's Table 7.1 of Conventional
Circuits gives 39m as the max length for a 6mmsq radial with a 32A Type
B MCB/RCBO, for "broadly all" installation methods including "directly
in a thermally insulating wall", so you look to be OK. However, 7kW
units are falling out of favour, with more power-hungry 8.4kW and
upwards being most widely available. Since cable cost is a small
proportion of the overall job, you'll be better future-proofed running
the circuit in 10mmsq, which would allow a later uprating of the MCB to
40A (45A only for the more restrictive clipped-direct,
embedded-in-plaster, or in conduit/trunking - not the
in-thermally-insulated wall case) allowing a future shower to be rated
up to 9.6kW.

This quick OSG lookup ignores other factors - cable grouping, higher
ambient temps, and so on; nor is it backed by any form of liability
insurance. It's a random collection of bytes apparently written at a
keyboard attached to a machine with the source IP address you'll see in
the headers; if following this advice makes your house burn down or your
visiting US-personal-injury-lawyer-just-using-the-shower fry, hard luck!

Stefek


Thanks a lot. Actually it's not for me, it's for a relative and he
will definitely be using 6mm because he says the small carpet tacks
he's using to clip the cable directly to the wall just aren't long
enough to go all the way through the 10mm stuff and still get a good
fix. Now that's what I call forward planning.


Cable clips *through* cable????

***WHOOSH***