Socket Ring Main Junction Box

A ring main more about ring mains can be found in our project here and also a radial circuit more about radial circuits in our project here will need a 30 amp junction box whereas a lighting circuit although you can buy 5amp junction boxes will need a 20amp junction box.

Socket ring main junction box.

These rules apply to spurs also. Locate the cable of the ring main as close to the new socket as possible. The number of spurs on the ring must not exceed the number of other socket outlets. To install a spur from a junction box you require a 30amp junction box.

Step one switch off electricity at the mains you will require two 30amp junction boxes and a length of 2 5mm2 cable the best way of using junction boxes to extend a ring circuit is to find the length of cable between the two sockets on the existing ring closest to the desired extension area. Trying to connect two or more is not only very difficult due to the number of wires involved it can also result in an abnormally high load at that point in the ring. Where you desire a socket leave a generous loop of cable out of the wall which can be attached to a new socket once the job has been successfully completed. There is no set limit to the number of sockets on a ring main as long as you stay within the rules mentioned above.

The diagrammes below show how you can break into a ring main with junction boxes to extend it. Run the new length of cable 2 5mm 2 round the room from one junction box to the other. These rules can be found in our ring main project. Attach the junction box to the plinth making ready for connection.