Lighting cable size

[spooky_b329]

Just a quick one as I can't find this in the Wiki...

My sparkie has left me with 1.5mm cable for rewiring my lighting. (running into new conduit I am channelling into the wall) However we will also be replacing the wiring going to some existing switches, and as the conduit is congested I was wondering whether I can use 1.0mm cable as sold in B&Q rather than the 1.5mm stuff my sparkie had lying around spare. Is 1.5mm overkill? 4 bulbs upstairs on one feed, and 4 bulbs downstairs on another feed.

Thanks

 

[Steve]

Its overkill yes, but many electricians use it anyway, I doubt your electrician just had it "laying around" as you say.

 

[RF Lighting]

I am one of those that NEVER uses 1.0mm² cable.

If I had given you cable to do the wiring in (which I wouldn't BTW), and you went out and bought something with a smaller CCC, I would not be especially impressed.

 

[spooky_b329]

Well to be truthful, he is a qualified sparkie and works for an electrical place but no longer does electrics, hence not part P accredited and possibly not up to date with the latest regs. Part of my extended family hence he may well have found it 'lying around', possibly at work

He has a Part P colleague who will be checking and signing off. I'm not doing any 'live' work, just running cable through conduit and leaving the ends hanging out at either end.

I'll check with him before using any 1.0mm though, thanks

 

[Steve3948]

I am one of those that NEVER uses 1.0mm² cable.

If I had given you cable to do the wiring in (which I wouldn't BTW), and you went out and bought something with a smaller CCC, I would not be especially impressed.

You must work for the council then.
Why don't you use 6242Y 1.0mm ??

I have asked many sparks over the years, why do you use 1.5mm and the answer is "because we do"

1.0mm 6242Y/6243Y meets all requirements of BS7671.

 

[RF Lighting]

TBH I don't install much 6242Y these days, and I certainly do not work for the council But you have to ask your self why it is all that councils use

But I use 1.5mm² as it has a higher CCC, so you do not need to worry when someone wants to cover it in insulation, or if you want a longer circuit length, or you want to add onto it later, increasing the circuit load etc.

For the difference in cost (which the customer pays anyway) what advantage is there for using 1.0mm²?

 

[Steve3948]

TBH I don't install much 6242Y these days, and I certainly do not work for the council But you have to ask your self why it is all that councils use

But I use 1.5mm² as it has a higher CCC, so you do not need to worry when someone wants to cover it in insulation, or if you want a longer circuit length, or you want to add onto it later, increasing the circuit load etc.

For the difference in cost (which the customer pays anyway) what advantage is there for using 1.0mm²?

RF, that was my point, I have asked many Electricians who work for the council why they use 1.5mm and they don't know !!!!!
It seems to be handed down over the years.

My problem with it, is it's size, it's hard work when used, connecting wall lights, ceiling pendants, J201 Joint Boxes, Chox Boxes and Dimmers.

However on some large installation I will install the first leg in 1.5mm

 

[ricicle]

IIRC our local city council use to insist on 1.5 for lighting and 10.0 min for cookers/showers whatever their rating!!

 

[RF Lighting]

My problem with it, is it's size, it's hard work when used, connecting wall lights, ceiling pendants, J201 Joint Boxes, Chox Boxes and Dimmers

Are you being serious?

1.5mm² hard to work with / terminate?

 

[ricicle]

My problem with it, is it's size, it's hard work when used, connecting wall lights, ceiling pendants, J201 Joint Boxes, Chox Boxes and Dimmers

Are you being serious?

1.5mm² hard to work with / terminate?

He wants to try and wrestle the 240mm² I was playing with the other day!

 

[RF Lighting]

4 core SWA?

Tell me about it

 

[Steve3948]

My problem with it, is it's size, it's hard work when used, connecting wall lights, ceiling pendants, J201 Joint Boxes, Chox Boxes and Dimmers

Are you being serious?

1.5mm² hard to work with / terminate?

He wants to try and wrestle the 240mm² I was playing with the other day!

Indeed I have worked on 240mm and 400mm.
Used to work for N.G Bailey, Balfour Kilpatrick, Mathew Hall, in fact most large Electrical Contracting companies.
I think I was termed a Journeyman Electrician, did 15 years travelling.
Got fed up with 7 days a week away from home, decided to sub to them for a period then decided to be an all rounder locally.

Anyway back to the topic, 4 X 1.5mm in a J201 or pendant not good.

 

[RF Lighting]

I'm not being deliberatly argumentative, but I have honestly never struggled to terminate 4no. 1.5mm² 6242Y cables in a ceiling rose.

 

[ricicle]

I'm not being deliberatly argumentative, but I have honestly never struggled to terminate 4no. 1.5mm² 6242Y cables in a ceiling rose.

It's all about how you dress the cables to start with

 

[RF Lighting]

Jeans and a tee shirt?