Which cable to us?

You need 2.5 mm twin and earth PVC to do it right

Not really. You can use flex if it is suitably protected, and conduit will do that.

The IEE wiring regulations stipulate that the cable must be of a certain size on a ring main or spur. That size is 2.5.mm it must be earthed so three core or twin and earth but yes suitably protected flex would do.

It's a very easy to work round cable which looks neat where it shows. And cable entries easy to weatherproof with a gland. Sold by the metre.

ISTM that if it's a 13A fused spur the installation method may allow

It would depend on the length of the run, but 1.5mm protected by a 13 amp fuse will be fine for most. Especially with surface run cable.

Thanks all for your help. It sounds like there is no extra requirement for it being outside vs an inside spur?

There will be 2 x double sockets and a light connected off an existing ip66 double socket. This socket is on an outside circuit protected by a separate consumer unit.

As it happens I do have some twin and earth kicking around.

Thanks

Lee.

If I see naked TW&E outside, it screams cheap job to me - even if perfectly safe. The 'correct' cable doesn't. And is much easier to make a decent looking job of than conduit.

Curiously, looking at gland prices, ones that are for flat cable seem to be much more expensive than round ones. The prices vary widely but Amazon see m to have round ones 10 for £2 ish but the flat ones seem more like £3 each. Am I missing something? With this price difference it woukd b e cheaper to buy the Hi-tuff and round glands vs using my spare T&E

I would assume the flat ones are either more difficult to produce or possibly just produced in smaller numbers thus missing out on cost savings associated with bigger production runs?

I double checked a couple of the ones I saw and they don't explicitly say t hey include the rubber cable seal - implying you have to buy it separately. If this is true, it could explain some of the difference but I can't find the rubber seals on their own :(.

Local water board run 2.5mm t&e along a barb wire fence ... clipping it to it with cable ties.

That made me think cheap job.

Hi all,

In my meter box (mounted to an exterior wall so the bloke from the leccy board can read it anytime) there is an RCD (30mA). The problem I'm having is that nearly every time there's a lightning strike within a mile of the house, the thing trips out for some reason. Fortunately we don't get many thunderstorms in my area, but when we do, it's a right PITA having to go outside in the pouring rain to re-set the thing time and again. Any suggestions as to how best to deal with this?

ta.

Is it a 'nuisance trip' or is it doing its job and protecting your supply? I think I would prefer an RCD tripping to a power surge.

It can be a right royal pin. I had this constantly. Any kind of surge and out when the 30mA.

It might have been an earth neutral short somewhere, or it might have been loads of RFI filters on the circuitry.

I uprated to 100mA RCD and put RCBOs elsewhere.

The trouble is that it is a "whole house" RCD and that the RCD is located outside.

Section 314 of the regs suggests that this installation is possibly not up to scratch.

Yeah, I've never come across one of these inside the meter box before.

I'll take a butcher's. I'm inclined to just disable the thing TBH unless someone can see any issues with doing that.

If you're on a TT earth then obviously that would not be a smart move.

NT

Well you would lose the RCD protection that you have. Without full details you may well be looking at a new CU.