Spur or new circuit?

[D Skelton]

Hi guys,

My latest customer wants a couple of extra sockets installed. He has no RCD protection and no spare ways in his CU. He is not wanting a new CU so I have concluded that the way I would like to do this job is to spur of an existing 32A MCB into a 1 way RDC board with 6mm cable. Then instal a radial circuit for the sockets from a 20A MCB in the RDC board. Now I can't see a problem with this but can any of you?

Also, am I right in thinking that as my installation would technically be a spur, and not a new circuit, I would only need to complete MWC?

 

[Amp David]

Both ends will be in the RCD. I'll be using 6mm cable to bridge the gap between the existing MCB and the new RCD and then essentially putting both ends of the ring into the RCD. I'll take one end of the existing ring and join it to one end of my extention within the CU, then I'll take the other end of my extention and put that in the RCD along with the remaining free end of the existing ring.

Sorry for the rather crude drawing but this is what I mean. Obviously in the drawing I haven't separated L,N & E, but it is just a rough sketch afterall haha.View attachment 5815

Cheers skelton, my mistake wasn't understanding what you are doing now with you sketch.

As for very I would do an eic for this as you are altering the circuits charateristics imo

 

[D Skelton]

I do believe I made this suggestion way back in post #6 !!! Was no-one listening?

I do apologise

 

[telectrix]

the reason i said EIC was if you are upgrading the earthing and bonding. that would alter the characteristics of all the circuits.