What is a ring main in a house?

A ring main, or final circuit, is exactly what it says on the tin. It is a ring of cables, usually 2.5mm carrying twin and earth wires, circling your home, carrying the mains electricity to sockets on the way. It gets the power from the consumer unit and delivers it to the sockets.

How many ring mains should a house have?





3 ring mains, 1 for the upstairs, 1 for the downstairs and the final one for the kitchen, this helps keep the power separated in case of a fault, so if their is a fault upstairs you will still have power downstairs and in the kitchen etc..

What is an electrical ring?

In electricity supply design, a ring circuit is an electrical wiring technique in which sockets and the distribution point are connected in a ring. It is contrasted with the usual radial circuit, in which sockets and the distribution point are connected in a line with the distribution point at one end.

What is a ring main supply?

ring main in Electrical Engineering



A ring main is a domestic electrical supply in which outlet sockets are connected to the mains supply through a ring circuit. Once the faulted circuit has been located, it can be isolated and grounded, via the ring main units, to allow safe repair work.

How do I know if I have a ring main?

Quote from the video:
Quote from Youtube video: Test calculate your expected r1 plus r2. Value then interconnect the line and neutral conductors.

How many sockets can I have on a ring main?





There is no limit on how many sockets you can install on a 32-amp ring main. However, the maximum load for a circuit at any given time should be 7,500 watts. Thus, while the number of sockets is not limited, the number of appliances and electronic devices you use at the same time could be limited.

Are ring mains still used?

Yes, ring mains (more correctly called ring final circuits these days) were and still are the norm for most UK dwellings. A very common arrangement was two ring final circuits, one for upstairs and one for downstairs.

Do kitchen sockets need to be on a ring main?

Best practice would be kitchen on its own 32A circuit. Whether you use a ring or radial is up to the electrician. Switched FCUs are a personal choice, not a requirement.

How many sockets can you spur off a ring main?

You can have one unfused spur per socket-outlet on a ring main or one fused spur per socket-outlet, you can have as many sockets as you like off of a fused spur.

What is the difference between a ring main and a radial circuit?



Ring circuit wiring offered a more efficient and lower cost system which would safely support a greater number of sockets. The lower costs aspect was related to fact that wires with a smaller diameter could be used, compared to radial wiring.

How does a ring main unit work?

A Ring Main Unit (RMU) is a totally sealed, gas-insulated compact switchgear unit. The primary switching devices can be either switch disconnectors or fused switch disconnectors or circuit breakers. Different combinations of these primary switching devices within the unit are commonly used.

What is the advantage of ring main system?

Ring main distribution system is the most preferred due to its following advantages: There are fewer voltage fluctuations at the consumer’s terminal. The system is very reliable as each distribution transformer is fed with two feeders.

How do I know if my socket is spur or ring main?



A general rule for a ring main is that if you only have two cables in the back of an existing socket then it is ok to spur. However, if you have a radial circuit with two cables coming in and out, this may be the last socket on that circuit and already has a spur.

How do I know if a socket is on a ring main?

Quote from the video:
Quote from Youtube video: Unit we normally take the neutral from one leg of the ring. And connect it to the line conductor on the other leg. So here you can see we've got the neutral from one leg of the ring.

How can you tell if two sockets are on the same ring main?

Plug the lamp into another outlet to determine whether or not that outlet is on the same circuit. If the lamp lights with the breaker still off, then the outlet is on a different circuit.

How can you tell if a ring main is bad?

Quote from the video:
Quote from Youtube video: So we find that on stage one of our continuity of our ring final circuit which is our end to end test between line neutral and cpc okay and which one have you got an issue with.

How do you trace a ring main?



1] I would temp disconnect one end of the ring from CU. 2] Teminate the lose ends isolated & insulated safley from each other. 3] Power the circuit back up as a temporary radial circuit. 4] Go round measure all your socket Zs values.

How do you wire a ring main in a house?

Quote from the video:
Quote from Youtube video: It. Then LT goes back into the same neutral bar. So here we have the neutral connection inside the consumer unit. And both wires go into the same terminal. And where you have the socket.