Is this par for the course?

[Stevos]

I have now checked and replaced all the metal switches and sockets (other than the cooker switch which seems to be on very short trails and difficult to inspect or remove), but found something unexpected with one of the sockets.

As mentioned, one of the metal double sockets has three additional plastic doubles spurred off it - which I know is not allowed.

What surprised me slightly is the arrangement of the wiring. I was expecting to see each socket spurred off the previous one in a chain- which is sort of what's there. Additionally there is a cable from the last socket back to the original metal socket, forming a kind of secondary ring branched off from the socket ring circuit.

This means that the original metal socket has four sets of wires running into it, with the consequence that the installer was unable to securely connect them, the terminal screws being loose, and causing the wires to fall out when unscrewing the plate to inspect them.

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• Stevos
• 24 Feb 2014
• 1

I'm not sure I understand the idea behind this spurred ring- whether it's an attempt or way to get around the regulations on spurred sockets, whether it's safer, or less safe than if they were just spurred without the loop back cable, or what was intended.

Since I don't yet understand it, I've left the loop of sockets in place, (unused) and just replaced the metal socket and connected it properly. The loop wires, sockets and boxes etc are all modern, and it looks like it's been put in relatively recently, though the wiring is in a plastic conduit running above the skirting board.

I'm guessing the whole spur will have to be removed or at least two of the sockets and the extra cable, but just wasn't sure quite what to make of it.

 

[AndyPRK]

safe way to sort that is to put a 13A FCU next to the socket, and connect the recent sockets through that

 

[Stevos]

safe way to sort that is to put a 13A FCU next to the socket, and connect the recent sockets through that

I assume that's safe as opposed to compliant with the regs, or would fusing it make it compliant also?

Also presumably if I fuse it, I'd have to remove the return leg of that spur ring - or the current could / would be shared between the two sides of the ring, and possibly avoid blowing any fuses (presumably even if I fused it on both sides.)

This is part of what is confusing about the extra bit of wiring returning from the end of the spur - that presumably functions in a similar way to a ring circuit, meaning that current is shared between the sides.

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• Stevos
• 24 Feb 2014
• 1

(Edit: There are many more sockets on the main socket ring, not shown for clarity)

Very peculiar. The socket being spurred from has connections each way to the ring, and also connections each way into the chain of spur sockets. Double ring.

It's like an infinity symbol. Maybe it's a perpetual motion machine for free energy

 

[AndyPRK]

you have two options. And it depends what you have plugged into the new sockets (or what is likely to be plugged in.

1) If low load equipment. (TV etc) do as I said before and fit an FCU. And make the sockets after it a radial. THat would be complient and safe.

2) The best way, if you have the tools is to incorporate the new sockets into the existing ring.

So one of the cables coming out the wall could be crimped/connect to the new sockets cable.

Then the other cable coming out the wall would goto that socket, and also connect to the last new cable.

Its the tidyist method if you can fit some crimps in the back of that socket box with a proper tool or suitable junction.

 

[phatboy]

Andy's idea sounds fine, but if the cables are already inside that backbox there is no need to crimp, just use some 30amp connector blocks to join 2 of the cables together, then it becomes a proper part of the ring.

Before going ahead though, I would turn off all power, and confirm with a multimeter that it is in fact a 'mini ring'!

 

[Stevos]

Hmm, thinking about it, I suspect they actually wanted it to be part of the socket ring, but just wired it wrong.

 

[JohnW2]

Hmm, thinking about it, I suspect they actually wanted it to be part of the socket ring, but just wired it wrong.

Quite possible - and, as has been pointed out, if the arrangements is as has been described, it would not take much to turn it into the single ring which may well have been 'intended'.

Kind Regards, John

 

[Stevos]

Thanks, I'll certainly consider changing it to be part of the socket ring as discussed.

The cabling for this can be seen in the photo above, and is run inside plastic trunking mounted above the skirting. It's the two white PVC covered cables seen coming out of the socket into the trunking below. It looks new-ish, but I don't know what spec etc. I didn't notice any markings but will check again.

Am I likely to cause problems incorporating this into the socket ring (ie is there any way to tell from looking at it if it's going to be sufficient for the (presumably) higher current that could run in the overall socket ring if multiple 13A devices are running connected to other sockets around the ring?

Also the cables for both sides of this part of the ring would be run next to each other in the same trunking as can be seen. Is this allowed, or likely to cause unwanted effects?

 

[SimonH2]

None of that's a problem. You aren't adding any extra load but changing the topology.

The only potential issue is that the ring would then be longer, but in practice it's very very unlikely that that is a problem (it tends to only be a problem for very large properties). Apart from actual/potential loads, the main constraint on the length of a ring is that the resistance has an upper limit - so as to guarantee enough current under fault conditions to blow/trip the fuse/circuit breaker.