What is a spur in electrical wiring

Spur – An electrical supply using one feed cable to a socket taken off a ring main usually used to achieve an extra socket without having to do too much work. See also Fused Spur.

What is a spur in wiring?

A fused spur is an electrical supply accessory that incorporates a fuse. This fuse, with a lower rating than the fuse for a ring man, allows an electrical supply using one feed cable to a socket to be taken off a ring main.

How do I know if a socket is a spur?

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 many sockets can be on a spur?

How Many Sockets Can Be on a Spur? Only one spur can be connected to a single socket.

What is a spur socket used for?

A Fused Spur Switch is commonly used for powerful electrical appliances, such as washing machines and dish washers that need to be installed without a plug; they are also used for electrical items that need to be installed on a separate cable from the ring main, for safety and maintenance purposes.

Can I put 2 double sockets on a spur?

you can have maximum one double socket as a normal spur but if you are going from socket to FCU fused at 13 amp from there you can add as many sockets as you wish as all the sockets and cable will be protected by the fuse so no chance of overloading the cable the fuse will blow first.

Does a spur need to be fused?

“The regulations state that the appliance needs to be fused, either with a plug or a fused spur. … So as long as the plug sockets are accessible without touching the appliance to turn it off then this is fine, but also a fused spur is fine too.”

Can you spur a light off a socket?

You need the neutral to make the light work but you can take a spur from the socket underneath the desk for a light, you could place a FCU next to socket underneath desk then run cable to light switch and then on to light fitting .. you cannot run spur to spur with sockets incase of over load of cable but a light is …

What happens if you spur off a spur?

The reason for not running two spurs from the same spur “point” is that it can lead to possible overloads in that one leg of the final can become unbalanced and exceed the max. allowed amps for a bit of 2.5mm if the tap off point is near the cu.

How do you identify a spur?

You can spot a spur on the map quite easily – it looks like a long, narrow tongue of contour lines, dropping away from a mountain top or a ridge. Usually its sides will be quite steep, but its top will slope gently downwards.

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What are fused spurs?

A fused spur is a switch that’s used to isolate electrical equipment from the mains supply. You’ll typically find them on the left or right of your oven or hob, and next to or underneath your heater.

How many Spurs are on a radial circuit?

As many as you want using 2.5 mm sq. Unfused spurs off a 30/32 A radial. One single or one twin using 2.5 mm sq. As many as you want using 4.0 mm sq.

How do you spur a socket?

Isolate the circuit at the consumer unit and use a socket tester to double check that the power is off. Then remove the faceplate from the socket you want to run a spur from. Count the cables entering the mounting box: one cable means it’s already on a spur; three cables mean it already supplies a spur.

Can I change a fused spur to a socket?

Hi. There is no problem removing 13amp fused spurs and replacing with socket outlets. You just need to ensure that those circuits (fuses/mcb’s) are backed up by a 30ma RCD as they will now be used to supply mobile equipment rather than fixed.

What is a 3 Amp fused spur?

A fused spur is an accessory to an electrical supply. An electrical supply can be taken off a ring main with the help of a lower rated fuse. … Unswitched fused spurs don’t have a manual on/off switch.

Can you spur off of a spur?

There is no problem in spurring off a fused spur (I think that’s what you mean). The principle is you just need to protect the cable. This week I’ve seen a unfused spur from a socket on the ring to a single socket (in 2.5 6262Y) – then from the single socket to a FCU in 1.5 6242Y for the boiler.

How long is an electrical spur?

The maximum length allowed for an unfused spur is 3m. The general rule of thumb, is that you can have an unfused spur at each socket, and one at the CU.

Can I add a fused spur?

As long as the job isn’t within a ‘special location’ such as a bathroom or outdoors, you’re also allowed to install additional new light fittings, switches, sockets and even add a single fused spur to an existing circuit (a ‘spur’ is a new cable and socket run as a branch from an existing socket on the ring main).

Is adding a spur notifiable?

Some minor electrical work will not be notifiable (see above). Examples include adding a lighting or power point to an existing circuit, adding a spur to an existing circuit or replacing a light fitting.

How many 13 amp sockets can a ring main have?

The IET Wiring Regulations (BS 7671) permit an unlimited number of 13A socket outlets (at any point unfused single or double, or any number fused) to be installed on a ring circuit, provided that the floor area served does not exceed 100 m2.

How many sockets can you run from a fused spur?

If the circuit is a ring circuit then an unfused spur can supply a maximum of one single or one double socket. A fused spur, as you propose, can supply an unlimited number of sockets with a maximum load of 13A.

Can I spur off a fused spur?

You can but you may risk overloading that spur causing the 13a fuse to blow what is your intended use for your garage sockets and your conservatory.

What cable is used for Spurs?

The unfused spur should supply just one single or one double (twin) socket outlet. It should be wired in 2.5mm2 P.V.C./P.V.C. T&E cable. There is no limit to the length of a spur, but Voltage drop considerations should be taken into account.

How much load can a spur take?

A spur is a single wire feed from one outlet with a max load of 20A (Fused at 13A usually but can be 15A or 16A so clearly you can’t run another spur from that and if trying to wire more than one spur into the outlet you will have a lot of trouble getting the wires from two spurs into the connections at the back of a …

Can I run lights and sockets be on same circuit?

Yes of course, for example desk lamps and other loads can be on the same circuit. However, there’s usually a special circuit for lighting because lighting pulls very little current, and so much thinner wire can be used, and so a separate lighting circuit is cheaper to install.

Can you spur a light off a ring main?

Running additional lights of ring main through fused spur is normally OK but not primary lights unless unless also emergency lighting is installed.

Can I spur off an outside light?

It’s fine. Put in a DP FCU before the light/pir and fuse down accordingly.

Are old spurs worth anything?

Unmarked spurs can still be worth a hundreds to thousands of dollars if they can be credibly attributed to a famous maker. So don’t completely discount your pair just because you can’t find a maker’s mark.

How many spurs come in a junction box?

Each socket outlet or junction box on the ring can only have one spur connected.

Which is better ring or 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. … Ring circuits provide low protection against overcurrents.