"PhilÅ" wrote in message
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wrote in message
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"PhilÅ" wrote:
Hello

I have just installed a bathroom fan which is on a timer...

Problem is...

fixed 240 V is from a 3A spur of the a socket ring on the RCB.

the light feed is not on the RCB.

So when connected up the neutrals are now common and the RCB is
tripping..

I take it I now have to connect the lighting ring to the RCB??

You should have taken all the feeds to the bathroom fan from a single
circuit, I'm pretty sure your wiring contravenes the IEE regs and, as
you've discovered, it doesn't work either!

--
Chris Green

Chris

If I take them from the mains ring (common) then this contravenes IEE is
dangerous, as the lighting ring could be switched off and the light live,
so
I am to take it all from the lighting ring...



I don't want to sound offensive I would suggest you get professional help
in.

You should never take a live feed of one circuit and a effectively a neutral
of another. If your case there is no longer a neutral current so there'll
immediately be an imbalance of current in the live and neutral flowing
through the RCD. It will trip as soon as you put any load on any circuit.