1mm or 1.5mm T&E for standard lighting circuit in your average house.

[static zap]

Do we have to factor in for global warming !
(how many editions ? ,-oz-weather guys have new stickers)

 

[MFS Electrical]

Personally I always use 1.5 I hate 1.0mm2 for a few reasons if the attic gets more insulation after I’m away then guaranteed the insulation will be laid over the cable reducing the ccc and if the customer decides in a few years to put up a chandelier in the hall the living room and a bedroom with 6 halogens in it and halogen downlights in the kitchen etc then there is the potential for overloading I also hate terminating 1.0mm it’s easy enough in wagos or ceiling roses but I always end up chopping it in the earth and nuetral bars of a CU even when it’s doubled over because it’s so thin and crappy just my personal preference

 

[Midwest]

Personally I always use 1.5 I hate 1.0mm2 for a few reasons if the attic gets more insulation after I’m away then guaranteed the insulation will be laid over the cable reducing the ccc and if the customer decides in a few years to put up a chandelier in the hall the living room and a bedroom with 6 halogens in it and halogen downlights in the kitchen etc then there is the potential for overloading I also hate terminating 1.0mm it’s easy enough in wagos or ceiling roses but I always end up chopping it in the earth and nuetral bars of a CU even when it’s doubled over because it’s so thin and crappy just my personal preference

But there's no rhyme or reason for your concerns.

1mm smothered with insulation, #6 with 6A ocpd, will be fine. With a 1.5mm, that could be 10A, what ocpd could you use, that would improve on 1mm?

An RFC could easily be overload, once you step out of the house. Wire RFC in 4mm?

1mm & 1.5mm have the same size cpc.

So that just leaves your nuetral?

 

[davesparks]

I believe there's still an argument for installing sealed unit LEDs, especially if you're planning to use 1mm.

What argument is that then? In what application would you select a cable size and then select your light fittings based on the size of the cable?

 

[Adam W]

What argument is that then? In what application would you select a cable size and then select your light fittings based on the size of the cable?

I thought I'd explained that in the previous paragraph - it's so the end user can't change a 7w light bulb for a 100w light bulb, thereby potentially messing up calculations or burning something next to it or whatever. In certain situations the tenants take the light bulbs out and steal them, so there's an argument there as well.

 

[Dave OCD]

1mm 99% of the time for me, the only time I prefer 1.5 is in a surface installation where there is a lot of surface clipping, 1.5 can be a little easier to dress and clip perfectly, mostly because the clips secure it that bit better.

 

[Dillb]

I thought I'd explained that in the previous paragraph - it's so the end user can't change a 7w light bulb for a 100w light bulb, thereby potentially messing up calculations or burning something next to it or whatever. In certain situations the tenants take the light bulbs out and steal them, so there's an argument there as well.

You never heard of diversity?

 

[Adam W]

You never heard of diversity?

yeah

 

[sparkdog]

Always use 1.5 don't like that thin 1.0 stuff.

 

[MFS Electrical]

But there's no rhyme or reason for your concerns.

1mm smothered with insulation, #6 with 6A ocpd, will be fine. With a 1.5mm, that could be 10A, what ocpd could you use, that would improve on 1mm?

An RFC could easily be overload, once you step out of the house. Wire RFC in 4mm?

1mm & 1.5mm have the same size cpc.

So that just leaves your nuetral?

I do agree to an extent but I still just prefer to install 1.5mm2 just makes me feel better? Think its all down to my journeyman instilling in me that 1.0mm was the devils cable and starting out my career in mostly commercial buildings that usually the minimum csa was 2.5 for lights and boy were they a bugger to install in a tamlite emergency bulkhead with the wee PCB terminals. I know there aint really no rhyme or reason I just wouldn't consider 1.0mm and always default to 1.5 unless the calcs specify bigger....

 

[MFS Electrical]

In certain situations the tenants take the light bulbs out and steal them, so there's an argument there as well.

I remember years ago getting called out to a building where all the lights weren't working, a day after they'd been re-lamped, some jakey had stolen all of the starters from the sides of the fittings

 

[MFS Electrical]

deleted - duplicate

 

[MDJ]

Out of interest what's most commonly used?

Pretty suprised you asked to be honest, surely it depends on what your connecting to the circuit? PS, 1.5mm2, well maybe 1.0mm2, or even 2.5mm2, hmm, where shall I start?

 

[Leesparkykent]

Pretty suprised you asked to be honest, surely it depends on what your connecting to the circuit? PS, 1.5mm2, well maybe 1.0mm2, or even 2.5mm2, hmm, where shall I start?

I'm on about a standard lighting circuit, in your standard house. For example if you was pricing/1st fixing a traditional built newbuild 2 bed semi with standard pendants...what would your usual go to cable be for the lighting circuits? Mine would be 1mm T&E others would choose 1.5mm T&E. I was interested in what is most commonly used, hence the poll.

 

[MFS Electrical]

I'm on about a standard lighting circuit, in your standard house. For example if you was pricing/1st fixing a traditional built newbuild 2 bed semi with standard pendants...what would your usual go to cable be for the lighting circuits? Mine would be 1mm T&E others would choose 1.5mm T&E. I was interested in what is most commonly used, hence the poll.

Go for 1mm2 if your doing a couple of new builds then the cost saving will soon add up (I know its a complete contradiction to what I said earlier but your not me so I assume you don't have the same reservations about 1.0mm that I do)

 

[Marvo]

There's a lot of mention of the reduced load of modern LED lighting but no mention of the sometimes appalling power factor and large inrush currents of many of the LED drivers and fittings that at least partially offsets that......

 

[HandySparks]

There's a lot of mention of the reduced load of modern LED lighting but no mention of the sometimes appalling power factor and large inrush currents of many of the LED drivers and fittings that at least partially offsets that......

True, but thinner cable will keep the inrush current down a bit.

 

[MFS Electrical]

True, but thinner cable will keep the inrush current down a bit.

And provide handy auxiliary heating for the gaff

 

[7029 dave]

When rewiring pulling through conduit switch drops etc, 1mm always,an if the circuit needed to be split into 2 circuits say per floor so be it. Never had to do this personally on bog standard 3 beds.

 

[loplug]

Almost always 1mm² for me as well and as mentioned before split to extra circuits if necessary