Socket Ring Main Junction Box

There is no set limit to the number of sockets on a ring main as long as you stay within the rules mentioned above.

Socket ring main junction box.

To install a spur from a junction box you require a 30amp junction box. The number of spurs on the ring must not exceed the number of other socket outlets. 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. Run the new length of cable 2 5mm 2 round the room from one junction box to the other.

The diagrammes below show how you can break into a ring main with junction boxes to extend it. These rules can be found in our ring main project. Locate the cable of the ring main as close to the new socket as possible. A new length of cable 2 5mm 2 should run between the new spur socket and the planned location of the 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. Attach the junction box to the plinth making ready for connection. These rules apply to spurs also. 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.