RCD protection for a socket required ?



Hello All.

I have a 16A B type MCB 'protecting' a radial circuit 2.5/1.5 T&E, (comprising of 1 x fused spur that was used for an old heater) further protected by a (100A /) 100mA rcd mainswitch in my 3rd floor flat. (TN-S- system). Part of this original cable run is 'concealed'.

I would like to fit a double socket near to where the spur is, for my cordless battery chargers.
Would it be correct to fit a 30mA fused spur instead of the existing spur, and cable to my double socket ???? or does my changing 'part' of the circuit mean that I need to 30mA the complete circuit ????
Even though the socket will have 30mA protection, the cable supplying the spur will only have 100mA ???

Many thanks for any advice. :oops:

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19 Jan 2005
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United Kingdom
Hi Ed

The way I would see it would be that as long as the new cables to supply the new socket are run in trunking (ie not concealed) then you could simply fit an RCD socket.

100mA don't count for diddly under the concealed cable rules.

However, a 16A rcbo would be about the same price and a better solution, although I guess you get caught up in Part Peee then.

Not sure why you have a 100mA RCD main switch on a TNS system?



Thanks for the reply SB.

Regarding my C/U, it was a council rewire job in 1994.
Strange but true, one goes they all go !!!!!!!!
Very poor design.

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