Drilled through 4 core lighting cable, how do I replace?

[TheFunk]

In the process of putting some kitchen cupboards up I drilled into some studwork and unfortunately a cable that was running through the middle of it. This tripped the downstairs lighting circuit and the main light in the lounge no longer works.

I thought I'd add in a replacement section using 2 junction boxes but on opening the cable up to my surprise it had 4 cores (red, yellow, blue and an earth). The cable has "Pirelli Cables 2000 2.5mm 6242Y BS6004" written on it.

This, following much Googling, doesn't seem like the easiest cable to get hold of in a hurry.
A friend has offered me 4 core cable with 1.5mm cores but I'm presuming you need to replace, or add in, like to like?

If so I'm guessing I'll need to wait until the electrical warehouses open on Monday and buy a drum for the 30cm's I need? As it's a lighting circuit will 20amp junction boxes be ok?

Thanks in advance.

 

[333rocky333]

Its an odd size cable to use and I would not think even an electrical wholesaler would have it in stock, what size was the Mcb that tripped, I assume 6amp, its likely you could use 1.5mm 3c and E
However you can not put just any JB in the stud wall it would need to be maintenance free, can you not reroute the cable so you have enough to join the two ends in 1 box

 

[terryplumb]

Its 3 core and earth ,in the older colours.
You could replace with the current version ,colours are brown/ black/ grey.
As the junction box's are probably not going to be accessible use maintenance free junction box's ,wago are my favorite.
Are you sure its 2. 5 mm² ?

 

[sparkwright]

It looks like 1.5mm2 to me, 2.5mm2 3 core+E is incredibly rare.

Best call it 3 core+earth cable - 4 core cable is something else.

Send a picture of the writing on the cable.

 

[sparkwright]

Somewhere like B&Queue or Wilko should sell small quantities of cable.

Maintenance free junction boxes are needed for this.

 

[TheFunk]

Thanks for all your replies.

Yes it definitely says 2.5mm² on the cable. It's indented on the cable rather than printed on, so it's hard to see (and photograph) I've rubbed some pencil over it so hopefully you can just make it out in the photo. It is 1 of 5 cables in there, all the same, so must have got a job lot...

Also attached is a photo of what tripped, No 6, is that 6amps?

I'll seek out a maintenance free junction box/es.

 

[TheFunk]

Actually 3 of the cables are slightly smaller (no writing I can see). The other two are a similar size but the writing isn't on the cable I drilled through so perhaps there is only 1 that's actually 2.5.

Thanks again.

 

[terryplumb]

If the cable that is damaged is smaller than the one marked 2.5 ,it will be 1.5.

 

[sparkwright]

That writing can't be on the cable you have damaged.

6242Y is 2 core + earth
6243Y is 3 core + earth

The cable number you have given is a 2.5mm2 two core + earth cable, typically used for a socket or immersion circuit.

You need either 1.0mm2 or 1.5mm2 6243Y cable, either size will suit your 6amp circuit breaker.

 

[mattylad]

Screwfix is open every day, they will have what you need.
Some cable, maintenance free junction boxes etc.

 

[Taylortwocities]

Here you are
Screwfix, 10metre length
https://www.screwfix.com/p/prysmian-6243yh-3-core-earth-cable-1-5mm-x-10m-grey/9678p

and a couple of these maintenance free junction boxes
https://www.screwfix.com/p/debox-2sl-screwless-in-line-junction-box/9858r

Screwfix are open tomorrow (Sunday). Sorted

next patient please

 

[winston1]

If it were me I'd be soldering the ends together and covering each core with self amalgamating tape followed by an overall covering of same tape. (NOT normal insulating tape though).

 

[333rocky333]

looking at your picture, do you actually need cable, looks to me like you can get slack or redrill the wood stud get a decent box and thru crimp it

 

[JohnD]

tape

Tape does not give adequate protection. You can use heat-shrink sleeving in the correct colours on the cores, but to give mechanical protection equivalent to the original sheathing, I think oval conduit is best. You can slide a length up the cable while working then slide it over your joint after.

There might possibly be an extra heavy grade of heatshrink you could use to replicate the sleeving, I have not seen it on the domestic market.

You do need a permanent, maintenance-free joint.

 

[SUNRAY]

If it were me I'd be soldering the ends together and covering each core with self amalgamating tape followed by an overall covering of same tape. (NOT normal insulating tape though).

Isn't this exactly what insulating tape was made for?


I take it you are referring to insulating tape and not PVC electrical tape.

But anyway, these days wrapping a joint in tape is a botch and yet another useless post.