extending ring main

[bendro]

I need to extend my ring main to fit a single socket + a fused fixed connector for an electric fire
There is a socket nearby if I dissconect one of the wires from this socket what is the best way of joining it I was thinking of terminal block inside a metal box covered with a blanking plate would this be acceptable

 

[Taylortwocities]

You could do that, but isnt there room in the back box of the existing socket?

 

[bendro]

Hi thanks for your reply
The existing socket has a 25mm metal box fitted so I dont think there would be enough room in that
If I replaced this box with a deeper box say 35mm would this give me enough room to use terminal connectors

 

[Taylortwocities]

Probably. It will depend on what sort of socket you have. Flat plate ones use up much more depth than standard white ones.
You'll find splitting the choc block into 3 separate pieces takes up less space than one chunk with 3 terminals.
Crimps are smaller still.

 

[ericmark]

Fitting a twin socket box to replace existing and two single sockets is likely the easiest way to extend a ring.

A ring circuit is considered to have a maximum length of 106 meters with 2.5 mm sq twin and earth to comply with the 5% volt drop with RCD protection which has to be provided for new sockets. You will need to measure and check the resistance of the existing cable to calculate if more cable can be added.

 

[bendro]

Can I use 15 amp choc block to connect 2.5 t+e
It seems to be a better fit than the 30 amp which seems far to big for 2.5 overlapped

 

[EFLImpudence]

No.

 

[17thman]

Do you have any test equipment to tell if it is a ring final. What is the fuse rating protecting the circuit?

 

[PrenticeBoyofDerry]

Can I use 15 amp choc block to connect 2.5 t+e
It seems to be a better fit than the 30 amp which seems far to big for 2.5 overlapped

No you need the choc block to be rated equal or greater than that of the circuits current.

There are a number of methods that can be used, would really depend where in relationship to the circuit and accessories of it, that the extras are being fit.
If you are having to chase out the walls and lift up flooring, I would personally try to eliminate joints and replace cables for new.
Or an alternative is the use of MF boxes that can be installed in inaccessible locations.
http://www.tlc-direct.co.uk/Products/ASJ803.html