Outdoor socket, regs, spur.

[EdinburghEd]

We have an outdoor socket that is hard wired into the ground floor power circuit and protected with an rcd in the consumer unit.
I now plan to add a spur from this outside socket via armoured cable to a new socket further down the garden.
Question
Should we install a double pole switch on this spur or can we simply take the new spur directly from the existing outdoor socket without a switch?

 

[littlespark]

You can’t spur from an existing spur unless the first spur is fused down to 13A or is on its own 16A breaker at the board.
Assuming the supply cable is 2.5mm, main power circuit is standard ring final circuit protected by 32A

Best option would be to add a switched fuse connection unit at the point of coming off the main house circuit with a 13A fuse.
You can add however many points you like after the fuse, and have a point of isolation within the house.

New build or modern house? Won’t be a big job to add in.

 

[EdinburghEd]

You can’t spur from an existing spur unless the first spur is fused down to 13A or is on its own 16A breaker at the board.
Assuming the supply cable is 2.5mm, main power circuit is standard ring final circuit protected by 32A

Best option would be to add a switched fuse connection unit at the point of coming off the main house circuit with a 13A fuse.
You can add however many points you like after the fuse, and have a point of isolation within the house.

New build or modern house? Won’t be a big job to add in.

Thanks for speedy reply but I do not appear to have worded my question so well. I will try again. The existing outdoor socket is hard wired into the ground floor circuit - it is not on a spur. It is a two year old property with the existing socket supplied by the builder.

 

[Avo Mk8]

Thanks for speedy reply but I do not appear to have worded my question so well. I will try again. The existing outdoor socket is hard wired into the ground floor circuit - it is not on a spur. It is a two year old property with the existing socket supplied by the builder.

Just to clarify, are you saying the outdoor socket is on the ring, and has both incoming and outgoing 2.5 t&e wired to it - ie each terminal in the back of the socket has two wires going into it?
If there are three wires in each terminal, that's a further complication!
What is the rating of the circuit breaker for this circuit? 32A or 20A or?

 

[EdinburghEd]

Just to clarify, are you saying the outdoor socket is on the ring, and has both incoming and outgoing 2.5 t&e wired to it - ie each terminal in the back of the socket has two wires going into it?

Yes - exactly as you said. I was attempting to show this as being on the main circuit (or ring) and confirm that the existing socket is fed byt two twin and earth cables 2.5 mm.

 

[Avo Mk8]

Yes - exactly as you said. I was attempting to show this as being on the main circuit (or ring) and confirm that the existing socket is fed byt two twin and earth cables 2.5 mm.

And on a 32A circuit breaker?
in which case you can spur off it!
Is your consumer unit a dual RCD type, or have RCBO's?

 

[EdinburghEd]

And on a 32A circuit breaker?
in which case you can spur off it!
Is your consumer unit a dual RCD type, or have RCBO's?

The ground floor circuit that controls the existing outdoor sockets is rated at 32a and in the consumer unit there are two rcd's each controlling approx half of the supply to the house. Both rcd's are rated at 100A.

I was always confident that I can spur from this outdoor socket but I was (and am) checking if the regs required me to have a double pole switch on the spur or if I can simply bring the armoured cable directly into the existing outdoor socket?

 

[littlespark]

Ah… I misunderstood.

Yes, you can spur off the ring, but again, only to one point.


I came across this exact situation, and I did what I suggested before… added a switch fuse inside the house and pulled the ring back from outside into a nearby socket…. (Was back to back with outside)
Then all outdoor sockets could be isolated.

There is no regulation that will stop you doing what you suggest, just additional functionality

 

[Avo Mk8]

The ground floor circuit that controls the existing outdoor sockets is rated at 32a and in the consumer unit there are two rcd's each controlling approx half of the supply to the house. Both rcd's are rated at 100A.

I was always confident that I can spur from this outdoor socket but I was (and am) checking if the regs required me to have a double pole switch on the spur or if I can simply bring the armoured cable directly into the existing outdoor socket?

I am unaware of a regulation that would require a double pole switch.
The issue for me would be selecting the right hardware to correctly terminate the swa cable and safely connect it into the existing outdoor socket, given this is all outdoors.

 

[EdinburghEd]

Many thanks to you all for your advice. I last added armoured cables for an outside socket about ten years ago (in a previous property) and I was chaecking if there were any "new" regs that I needed to be aware of.
I have seen a youtube video of someone fitting a socket in similar circumstances to mine but he added a double pole switch at the junction with the existing socket.
I now understand that this was for convienience rather than meeting a 'new' regulation.

All resolved with your help and I now feel confident to proceed.
Thank you.

 

[westward10]

Use outdoor cable glands and ensure the armour of the cable is earthed.

 

[EdinburghEd]

Outdoor cable glands and cable purchased already. Earthing kit in stock. I have watched videos of fitting kit and will add silicone to seal cable entry and screw holes!
So I am now quietly confident that I will safely complete this mini project even if it takes me rather longer than someone who deals with similar jobs on a regular basis.

How do I sign my question off as "resolved" now?

Thanks again.

 

[littlespark]

I hope it wasn’t a video of that outside socket that got chased into the wall…..

There are “weatherproof” SWA glands available… ie 20CW…. The 20BW are not weatherproof…. Or you can get the “Storm” glands which are also IP rated.

This is where an isolation switch indoors comes in handy…. If you get moisture into the outside socket, you can turn it off and still have indoor sockets until repaired.

 

[DPG]

One tip, which you might ready know - drill a small weep hole in the bottom of the outside socket back box.

 

[EdinburghEd]

I hope it wasn’t a video of that outside socket that got chased into the wall…..

There are “weatherproof” SWA glands available… ie 20CW…. The 20BW are not weatherproof…. Or you can get the “Storm” glands which are also IP rated.

This is where an isolation switch indoors comes in handy…. If you get moisture into the outside socket, you can turn it off and still have indoor sockets until repaired.

The glands I have purchased are ip66 rated as is the outdoor socket that I will be using.
The codes you are quoting are unknown to me. Should I also be looking for 20CW?

 

[littlespark]

Any ip66 gland is fine. 20CW is just the manufacturers code for it.

Actually, make sure your glands are for SWA, not just a compression gland with a rubber ring that closes up when tightened

 

[EdinburghEd]

Any ip66 gland is fine. 20CW is just the manufacturers code for it.

Actually, make sure your glands are for SWA, not just a compression gland with a rubber ring that closes up when tightened

This is the kit I purchased (from Screwfix - see link below.) I have assumed that this will provide the appropriate fixing. Am I correct?

https://www.NoLinkingToThis/p/deta-brass-exterior-gland-kit-20mm-2-pack/637vt?ref=SFAppShare

 

[littlespark]

Yeah, that’s exactly the same as a 20CW.

The armour is gripped between the two brass parts for earthing purposes, then the compression part is tightened around the outer sheath of the cable to create a waterproof seal.
Then the shroud is slipped over the top of all of it.