Ring off a spur - electrician

Horlock

I'm pretty sure that these days that you are not allowed to run a spur off a spur, what I was wondering was how to run a garage.

More specifically, whether if you run a spur to the garage and then have a garage consumer unit (something like http://cpc.farnell.com/1/1/56478-garage-consumer-unit-gu5631632-pro-elec.html) whether you are then free to run a separate ring for sockets and a spur for lights from this unit.

Thanks

andyhop

No!

Do you not have space in your existing consumer unit to run a new ring or radial in . Cable size depends on run distance,insulation etc and loading

Would suggest speaking to a local spark

Horlock

andyhop wrote: »

No!

Do you not have space in your existing consumer unit to run a new ring or radial in . Cable size depends on run distance,insulation etc and loading

Would suggest speaking to a local spark

At the moment I don't even have an existing consumer unit. I currently have an old fuse box and the power sockets in the garage are run off the lights (which is a spur)! So was contemplating a vague improvement while not rewiring the whole house, but in such a way that when I get around to rewiring the whole house I wont have wasted any money.

Ectophile

You'll need to make sure you can't overload the spur that feeds the garage. the usual rule of no spur off a spur is that the ring is fused at 30A, but the individual cables are rated about 18A (it varies a bit depending on whether the cable has ventilation). So a single spur feeding one socket isn't going to get overloaded, but spurs off spurs can easily overload the cable.

That would mean fitting a sufficiently low rated breaker in the garage consumer unit to keep the current down.

Horlock

Thank you very much.

I_have_spoken

I've used a ring from my garage consumer unit (40A 30ma RCD), hooking up sockets in the garage for washing machine etc, outside sockets off an RCD, the combi-boiler and PIR outside lights. Works fine.

zaax

You can spur off a spur, if the spur first goes though a 13amp fuse.

Though if its for a shed you may need a 15amp supply if you're going to be using cutting tools