In message ,
"Owain" wrote:

"Martin Angove" wrote
| In this case the fan has two live connectors. One to power the fan
| and electronics and one connected to the switched live feeding the
| lamp(s).
| I would have thought that your idea is bloomin' dangerous ...
| consider the case where the fan actually connects "SL" to "PL"
| internally, perhaps in a fault condition (who knows what the
| electronics do?). In this case you have created a huge circuit,
| partly wired in (usually) 2.5mm cable, partly in (usually) 1mm
| cable and protected by what amounts to probably a 38A MCB (32A+6A).

And if the lighting circuit in the bathroom and the socket circuit borrowed
from (because there shouldn't be a socket circuit in the bathroom ...)
happen to be on different phases ....



Well, yes, though this isn't often the case domestically :-) I thought
of another reason for not doing it - anyone who doesn't know the system
won't know how to isolate it, other than perhaps through the 3-pole
isolator which is supposed to be fitted these days.

I "Googled" back on the thread a bit, as the earliest post I have on my
system here is Mark Evans's on the 30th November. I notice that PoP's
original suggestion was to wire the permanent live through a 3A fused
spur... still not a good idea for all the reasons already mentioned, but
very slightly less bad than straight from the sockets circuit.

Got very confused with some "early" postings under the heading
"Extractor Fan"... it seems that this is at least the second thread on
the subject, and the previous one was in 2002 :-)

Hwyl!

M.

--
Martin Angove: http://www.tridwr.demon.co.uk/
Don't fight technology, live with it: http://www.livtech.co.uk/
.... Sometimes you just have to say 'What the heck'