Number of sockets on one spur

[Cigaro]

Guys,

I spend a lot of my spare time building and hacking gadgets and tinkering with electronics in general, so I've decided to build a proper workbench in my workshop.

As part of this I want to install sockets atop the workbench; extension leads are messy and this way I can have as many sockets as I like.

My plan is to spur off from a socket on the ring final through a 13A RCD fused spur and power probably five sockets from this spur, which will be mounted on the counter top.

I am aware that it is possible to plug far more than 13 amps' worth of gear into five double sockets, but it's simply not going to happen - the sockets are for things like power supplies, soldering irons and the occasional drill.

As the spur will be protected by a 13A fuse, is this going to be an issue regulations-wise? I'm sure I remember hearing somewhere that you can only have one socket on a spur, but is this situation different? Obviously the reason for this rule would be to avoid overloading the 2.5mm T&E feeding the sockets, but as the whole lot is fused at 13 amps I don't see how this can happen.

Cheers.

 

[holmslaw]

,,

 

[PrenticeBoyofDerry]

You can use your method of a 13A fused RCD protected spur and have the five extra sockets, you quite rightly state that any load over 13A could cause overload and fuse to break. You could also have this in 1.5mm T&E providing there are no de-rating factors.
What I would like to know is whether you already have RCD protection on the circuit you are spurring from, if so there is no real need to have an RCD fused spur, you could get away with just a fused spur.

 

[Cigaro]

Hi PrenticeBoy,

No, there is no RCD protection anywhere in this house. It's just a peace of mind thing really, if any piece of equipment on the workbench is ever faulty I'd rather have the additional protection of an RCD.

 

[ericmark]

I have used active RCD protection many times for workbenches and also for grinders so that with a power cut when power is returned nothing will auto start. Simply they are easier to fit than a contactor to do same job and also work as a RCD as well.

The word Spur. A branch from a ring or radial final circuit. Is confusing as of course a branch from a radial circuit is also called a radial that's all a radial circuit is a load of branches radiating out.

Where there is a reduction in the current carrying capacity of a circuit you are with some restrictions allowed to fuse at the destination rather than the origin. See 433.2.2. The fact that we have fuses in all our plugs using a single socket outlet be it single or double is considered as being fused at destination so you are allowed to run a single 2.5mm cable rather than two to just one device socket or FCU. But once you fuse down you can add as many as you like.

A non fused spur also needs its length not exceed 3 m, it is installed in such a manner as to reduce the risk of fault to a minimum, and it is installed in such a manner as to reduce to a minimum the risk of fire or danger to persons.

I would prefer it if we called fused spurs radials and only called un-fused spurs "Spurs" but that's not the case.

There are a few anomalies we call the ring a "ring final circuit" but we take from that with fused spurs so it's not the "final circuit" in that case. Also "Competent" is a higher level than "Skilled". Nothing we can do about the English used we just have to accept it.