Discuss Floor socket - 2 sets of T&E? in the DIY Electrical Advice area at ElectriciansForums.net

Welcome to ElectriciansForums.net - The American Electrical Advice Forum
Head straight to the main forums to chat by click here:   American Electrical Advice Forum

Cupa

-
DIY
Reaction score
7
Before I moved into my flat, it had undergone a quick makeover and as part of that some wiring work was carried out including some extra sockets. I was told that under the kitchen breakfast bar there is T&E already there, it's just that the previous owner never installed a socket there but the wiring is there.

So yesterday I dived under and had a quick look. After taking electrical tape off each core, I discovered there are 2 sets T&E. I bought a 1 gang Contactum 13A floor socket and wired it in:

(a) with just one T&E attached
(b) with both T&E cables wired up together

And it works either way absolutely fine (note: I cut the T&E shorter afterwards and then took the image you see attached).

My question is whether I should go with option (a) and just tape the other core up properly or option (b)?

Floor socket - 2 sets of T&E? floor socket - EletriciansForums.net
 
Option C: See where both cables come from and make sure they are not coming from a spur.
 
I think it would be best to get an electrician in to confirm where those cables run to and from (and pop a second grommet in that back box). Connecting cables without knowing exactly what they are for is not a good idea.

Chances are it's part of a ring final circuit but you need to be sure. If it is a RFC and the cables were pretty much as shown in your photo, albeit with some tape over the ends, then for several reasons, it was not left in a safe state.
 
100% those cables are for a floor socket, in terms of where they run from I can tell you exactly what other items are on the same MCB if that is what you meant?
 
100% those cables are for a floor socket, in terms of where they run from I can tell you exactly what other items are on the same MCB if that is what you meant?

Not really mate.
Need to know where each cable wires to. Not the MCB in the CU. Before that. Are they wired to a spur, junction box, another socket on the RFC.
As above, it sounds like these cables were not initially connected up.
 
Right, not sure how much help this is, but this is a picture I took when looking around the place before I bought it and I noticed this cable sticking out the floor under the breakfast bar - it was joined up at the time.

Floor socket - 2 sets of T&E? Original Cable - EletriciansForums.net
 
So it was connected..
Your comment "After taking electrical tape off each core, I discovered there are 2 sets T&E." threw me.
Still could do with knowing where each cable come from. Without knowing how can you be sure if its to regs.
 
The only way to verify would be to carry out some basic inspection and testing to see where they are fed from.

And were they live coiled up like that?
 
How were the cables before you started? Were the 2 joined together (ie L>L, N>N, E>E). Were they installed in that back box already?

As you say it seems likely they are for a floor socket.

If they are part of a ring the 2 should have been connected together, and you need to make sure they are still connected together properly by carrying out certain tests once the socket has been installed. Failure to do this could result in other parts of the circuit becoming overloaded, especially in a kitchen.

If it isnt part of a ring then connecting both cables together could make something else live which may not have been installed/terminated. Altbough if the socket works with either set of cables individually, then both are live and its likely part of a ring.
 
Most likely scenario (given that we now know they were connected together) is that they're part of a ring, in which case you'd use both sets connected together to add a socket to the ring.

However, that's not guaranteed, for all we know they could be two separate spurs from different parts of the ring, or different rings entirely, in which case they definitely shouldn't be connected together.

If it were me I'd be wanting to check the entire ring for continuity with/without that socket installed and r1+r2, so I knew everything was definitely in order. (That involves opening your CU though, so definitely not a DIY job unless you're particularly competent.) A less thorough approach that may still be deemed acceptable would be to trace those cables to see where they go, and check they're going from / to other parts of the same ring (rather than to a spur). Even then though, you run the risk of gaining a sense of false confidence if all is not as it seems!
 
Doesn't sound like it is, as they were not initially connected up.

Agreed but that does not mean they were not intended to be a RFC.

My above comment was posted before the pic.
The intention may be for the choc block wiring to be part of the RFC but without fully testing there is no way of making sure it was.... or asking the person who wired it up..
 
My above comment was posted before the pic.
The intention may be for the choc block wiring to be part of the RFC but without fully testing there is no way of making sure it was.... or asking the person who wired it up..
No worries. I was referring to the two curled up cables in the back box in the original picture,thinking it was a 'broken' RFC with two taped up cables in a back box. All makes more sense with the extra info - hopefully the OP will get an electrician in to check!
 
I went and had a good look and from what I can tell, it's deffo not leading to a spur. I then went and looked at the paperwork that I have and got the details of the guy who did the testing and inspection on the place before I ended up there. Call him, sent him a pic and he said from memory its a ring, so both need to be connected, explains why they were connected initially I guess.

From a learning perspective, what would happen if only one of the T&E cables was connected and the other not?
 
From a learning perspective, what would happen if only one of the T&E cables was connected and the other not?

You would end up with two radial circuits, wired in 2.5mm, both connected to a 32A breaker... Which is not good.
 
You would end up with two radial circuits, wired in 2.5mm, both connected to a 32A breaker... Which is not good.
...and those radials wouldn't, aside through complete coincidence, be evenly split either.

If that socket is the first or last on the ring, you could easily end up (effectively) converting your ring into a single 2.5mm radial with a 32A breaker on it...
 
If that socket is the first or last on the ring, you could easily end up (effectively) converting your ring into a single 2.5mm radial with a 32A breaker on it...

That's what I basically said. You can't go pinching my waffling on this forum...
I demand payment... With cheesecake..
 
A Ring final circuit allows 2.5mm cable (which can only carry around 20A in some circumstances) to be used with a 32A MCB on a 32A circuit. This works because every socket has 2 routes back to the MCB (either way around the ring) so the current is divided between the 2. As others have said, if you creat a break in it somewhere, up to 32A could flow down one leg and via one 2.5mm cable, overloading it.

It is a wiring method not often found outside the UK, and was devised after WW2 to save copper. It is safe enough when a properly wired in a ring with sound connections, but its very easy to leave in a dangerous state if modified incorectly.
 

Reply to Floor socket - 2 sets of T&E? in the DIY Electrical Advice area at ElectriciansForums.net

OFFICIAL SPONSORS

Electrical Goods - Electrical Tools - Brand Names Electrician Courses Green Electrical Goods PCB Way Electrical Goods - Electrical Tools - Brand Names Pushfit Wire Connectors Electric Underfloor Heating Electrician Courses
These Official Forum Sponsors May Provide Discounts to Regular Forum Members - If you would like to sponsor us then CLICK HERE and post a thread with who you are, and we'll send you some stats etc
This website was designed, optimised and is hosted by Untold Media. Operating under the name Untold Media since 2001.
Back
Top
AdBlock Detected

We get it, advertisements are annoying!

Sure, ad-blocking software does a great job at blocking ads, but it also blocks useful features of our website. For the best site experience please disable your AdBlocker.

I've Disabled AdBlock