UK Re using a 10mm cable to provide a new ring

[pal1952]

I would like to reuse a 10mm cable to provide a ring circuit in an area. The cable is currently used for an electric shower, still connected at present and is fine. When the shower is removed I intended to replace the 40A breaker with a 32A, slightly reroute the cable and add a ring to then end. I have no idea where regs might stand on this however I can see no electrical reason why it should not be ok. I imagine that rerunning the ring will be suggested but that is easier said than done. Any thoughts.

 

[littlespark]

It’s known as a lollipop ring, or lollipop circuit.

Not very common, but doable.
Make a note of it on the test sheet under “departures”

 

[davesparks]

Make a note of it on the test sheet under “departures”

What is the departure?

 

[DPG]

What is the departure?

I think his intention is to mention it on the paperwork just to make sure future electricians know there is a non conventional circuit on the installation.

 

[davesparks]

I think his intention is to mention it on the paperwork just to make sure future electricians know there is a non conventional circuit on the installation.

That's not a departure and shouldn't be recorded as such.

 

[DPG]

That's not a departure and shouldn't be recorded as such.

Technically yes. Maybe a note attached to the report?

 

[davesparks]

Technically yes. Maybe a note attached to the report?

If you want the next electrician to have a chance of seeing it then put it on the circuit list attached to/near to the CU.

 

[DPG]

If you want the next electrician to have a chance of seeing it then put it on the circuit list attached to/near to the CU.

Or do both.

 

[littlespark]

If you are implying that the customer doesn’t keep a hold of the test certs for any future sparky… then why do we bother filling them in at all?


Whether it’s recorded as a departure or somewhere else… I just meant it should be noted somewhere.

Any future spark working on a board should have enough common sense to realise if say, circuit 1 is a 10mm, but circuit chart says sockets… then there’s something unusual going on. Quick read would confirm it’s by design and not a mistake.

 

[pal1952]

Thanks for the comments, all valid. More info it better than less (or none). I will mark the board to indicate that the circuit is "lollipop".

 

[pc1966]

The more common example of this has an isolator switch at the feed -> RFC point, for example, for a laboratory/classroom/etc.

You don't need one here, but at least an accessible and labelled junction box location is good, such as a blanking plate on the old cooker outlet, etc. 10mm is too big for the usual Wagos, but you might find something of adequate rating to fit in there.

 

[Risteard]

Just seeing this thread now, but the awkward part will be finding a suitable way to joint 10mm^2 cable to your 2*2.5mm^2 cables.

 

[MDJ]

Thanks for the comments, all valid. More info it better than less (or none). I will mark the board to indicate that the circuit is "lollipop".

No do not do that, it is rough and not the way. you could take the 10mm2 cable into a little enclosure with a lid and a double pole isolator switch and connect it to the top, then the 2 2.5mm2 cables of the new ring to the bottom, label the enclose and then that is better that a lollypop connection. the enclosure could be fitted in a cupboard or somewhere less noticeable to the eye whilst acting as a connection box and isolating switch. Personally I don't even like that idea but better than a lolly pop connection.

 

[MDJ]

Just seeing this thread now, but the awkward part will be finding a suitable way to joint 10mm^2 cable to your 2*2.5mm^2 cables.

Absolutely mate, totally agree, I have made a suggestion but am watching this thread closely.

 

[davesparks]

No do not do that, it is rough and not the way. you could take the 10mm2 cable into a little enclosure with a lid and a double pole isolator switch and connect it to the top, then the 2 2.5mm2 cables of the new ring to the bottom, label the enclose and then that is better that a lollypop connection. the enclosure could be fitted in a cupboard or somewhere less noticeable to the eye whilst acting as a connection box and isolating switch. Personally I don't even like that idea but better than a lolly pop connection.

How would that be any different? Other than adding an isolator, which nobody will ever use, and will be just another potential point of failure, but hat does it achieve?

And what is wrong with the lollipop circuit?

Just because a circuit doesn't comply with the standard circuits laid out in the on-site guide it doesn't make it any less valid or compliant.

 

[MDJ]

How would that be any different? Other than adding an isolator, which nobody will ever use, and will be just another potential point of failure, but hat does it achieve?

And what is wrong with the lollipop circuit?

Just because a circuit doesn't comply with the standard circuits laid out in the on-site guide it doesn't make it any less valid or compliant.

Hey Dave I understand your point, as said in my reply I don't really like the isolator either, but it is good for connecting a 10mm2 to 2x2.5mm2 cables tight and securely, I am wondering how the 10mm2 and the 2 new 2.5mm2 cables are to be joined to create a lollypop, I have seen this before. One way is to join it through with crimps which I think is carp, yes you can get crimps with a 10mm2 hole one side and a 6mm2 the other, but where are you doing this? under the floor, in a JB ? I am unsure, My suggestion is without doubt not great but I have seen it done and I think better than crimping it through, lets see what the OP comes back with, happy to hear your preffered method too.

 

[Yellowhammer]

Could stick something like this in a little box on some din rail to get the connection. In a cupboard much like the isolator would be really, would be maintainable and hits the required CSA needs as per manufacturers spec. Would be much nicer with stranded cables and some double ferrules!