Adding a socket outlet - extending the ring main

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Plan for the new socket outlet

Rather than adding a spur to a ring it may be advantageous to extend the ring.

This is done by inserting a longer length of cable between two of the sockets on the existing ring.

Switch off the power at the consumer unit and remove the fuse for the circuit. Establish the route taken by the ring main and decide upon the two sockets between which it is best to extend.

Adding the new cable

Lay cable from the first socket, taking it to the new socket(s) along the way, and on to the second socket. Remember to allow sufficient cable for making connections.

Fit the new socket(s) connecting the cables as you go.

Connecting the cables at both original sockets

Remove the face plates of these two sockets between which you are extending the ring main.

Remove the pairs of conductors from each terminal.

Establish which cable is the original one travelling between your two sockets and remove it.

There should be room to feed one end of your new cable into each of the boxes where you just removed the old one.

If not, remove one of the other blanking plates in the box to provide entry for the new cable. Fit a rubber grommet to the new entry hole and feed the cable in so that there is sufficient to allow for connection.

Strip and prepare the ends of the new cable ready for connection. Protect the exposed earth conductor with green/yellow sleeving.

Taking the conductors of the new cable, one at a time, twist each together with the corresponding one from the remaining original cable. Now insert the pairs of conductors into the correspondingly labelled terminal.

Two red conductors to the terminal marked live (‘L’).

Two black conductors to the terminal marked neutral (‘N’).

Two green and yellow conductors to the terminal marked earth (earth symbol).

Tighten the screw of each terminal ensuring that the conductors are firmly held and that the insulated part of each butts right up to the terminal.

Fixing the socket outlet

Double check your connections at both these sockets, and ease the face plates back to the boxes folding the cables carefully as you do so.

Re fix the retaining screws, tightening them alternately to draw the fascias back evenly against the surface.

Once you are sure that all work has been completed correctly, replace the fuse for the circuit, switch the power back on, and test.

• Supply new socket from another socket
• Supply new socket from a junction box
• Mounting socket boxes