Ring Main Circuit Wiring

Wiring a socket correctly in a final ring circuit or ring main.

Ring main circuit wiring. The wiring in a house connects all appliances together in parallel. The cable used in domestic ring circuits is either 2 5sq mm or 4 0sq mm twin core and earth these are rated in free air at 24amps or 32amps respectively. In electricity supply design a ring final circuit or ring circuit often incorrectly called a ring main a term used historically or informally a ring is an electrical wiring technique developed and primarily used in the united kingdom and to a lesser extent in ireland this design enables the use of smaller diameter wire than would be used in a radial circuit of equivalent total current. It includes in one unit two switches that can connect the load to either or both main conductors and a fusible switch or circuit breaker and switch that feed a distribution transformer.

The other type of circuit used to power your home is a radial circuit. They are not so common in the uk but are used extensively abroad as the ring main or final ring circuit does have it s drawbacks. Always isolate any electrical circuit before working on the circuit. By using a junction box and connecting into the ring circuit cable.

In the exam you may have to interpret a diagram of the ring main similar to this one. The upstairs ring final circuit is probably only loaded to a few amps and in theory a much smaller circuit could be used. In modern domestic properties in the uk the main electric lighting circuits are separate from the power ring main circuit. The cable of the ring circuit consists of a brown live wire a blue neutral wire and a bare copper earth wire all three being enclosed by an outer pvc sheathing.

I consider it good practice to install a 32 amp ring final circuit so as to facilitate the use of several electric heaters in case the central heating breaks. In this video i show how to wire a spur socket to a ring final circuit using 2 methods 1. Each protected by a 5 amp fuse or 6 amp trip in the consumer unit. Each house should ideally have at least two lighting circuits.