10 amp lighting MCB

[Guitarist]

Is anyone using 10 amp MCB's with 1.5mm for domestic lighting circuits yet (as per electricians guide to building regs) or are most of you still going with 6 amp?

Wondered if anyone had come across any lighting switchgear not rated at 10 amps

 

[ackbarthestar]

I've installed a couple in the past.

Yes, I agree, you do need to watch out for the cheaper B&Q type light switches rated at something other than 10A.

 

[Baker1988]

So do all domestic lighting circuits have to be 10 amp now?

 

[malcolmsanford]

Most BS 67 ceiling roses are rated 6amp only

 

[malcolmsanford]

So do all domestic lighting circuits have to be 10 amp now?

No .............................as the designer you decide

 

[telectrix]

and dont forget, those switches have only to carry the load of whatever light/s they control, not the whole circuit load.

 

[telectrix]

back to the 12 x 50watt downlights again. LOL.

 

[ackbarthestar]

I remember having this debate back in 1990. A chap stated that all lighting cables should be 1.5mm2 to which I showed him the regulations and proved for the basic lighting circuit covering a nominal 12 GLS 100W lamps (we used to use them once upon a time!) a 6A MCB with 1.0mm2 T&E was sufficient .

With the modern LED lighting you could probably tripple that number of outlets without undue stress to the lighting circuit, not so with 50W Halogen downlights

 

[Guitarist]

Personally, I like 1.5mm on lighting circuits. I have found it to be far more robust than 1mm. Just my preference.

 

[Amp David]

For some reason I always use 1mm for switch drops. Don't know why, just the way do it.

 

[telectrix]

For some reason I always use 1mm for switch drops. Don't know why, just the way do it.

only because you can't be arsed to mark the switch wire. LOL.

 

[Amp David]

Could be, or I'm a tight arse

 

[mogga]

hotel im working in has just had a visit from someone to look at their energyefficiency and any improvements that can be made His first thing mentioned was my fav things HALERS LED for replacing halogens and also the 2x26w thorn chalice type fitting now has an LED equivelent He said they also mention in passing on the report how LEDs pull less current than halogens hence create less hot spots in trunking,conduit systems

 

[Guitarist]

For some reason I always use 1mm for switch drops. Don't know why, just the way do it.

Now if you were talking 1mm flex, I'd be with you there. Think how much easier wiring would be if it was all flex...twin bootlace ferrules for ring finals, no fighting with shallow back-boxes...

 

[Octopus]

1.0mm on two way lighting switching everytime

 

[Guitarist]

hotel im working in has just had a visit from someone to look at their energyefficiency and any improvements that can be made His first thing mentioned was my fav things HALERS LED for replacing halogens and also the 2x26w thorn chalice type fitting now has an LED equivelent He said they also mention in passing on the report how LEDs pull less current than halogens hence create less hot spots in trunking,conduit systems

Shame they didn't just pay you to tell them the obvious

 

[demkap]

hi there just wondering any calculations for working out cable size. so example i have a 9.6kw shower what breaker and cable size do i have to use?
also with wired in smoke detectors can they be wired say off a socket circuit or a fused spur in use or does it have to have its own circuit?

thanks

 

[ackbarthestar]

hi there just wondering any calculations for working out cable size. so example i have a 9.6kw shower what breaker and cable size do i have to use?
also with wired in smoke detectors can they be wired say off a socket circuit or a fused spur in use or does it have to have its own circuit?

thanks

I can't see you getting a shower on a lighting circuit unless you wired your lights in 6.0mm2. There are those who may try it.....

Maybe you're likely to get an answer if you posted this query on the instantaneous water heater forum

 

[Guitarist]

I would suggest getting an electrician to sort these jobs out tbh

 

[telectrix]

hi there just wondering any calculations for working out cable size. so example i have a 9.6kw shower what breaker and cable size do i have to use?
also with wired in smoke detectors can they be wired say off a socket circuit or a fused spur in use or does it have to have its own circuit?

thanks

same post on a different thread, you said you were competent. how can that be if you don't know the basics af calculating cable size from load and length of run?

 

[Amp David]

Beat me to it Guitarist!

Questions such as this just proves you haven't even the smallest idea of electrical work.

I'm out:waving:

 

[Baker1988]

I personally use 1.5 for all domestic lighting i have never come accross a domestic circuit with enough lights on it to need more then 6 amp mcb although i have been in a flat with 2 pendants and 3 downlighters and that was on an 10 amp c type industrial breaker

 

[Andy78]

Only ever used 10A when I was doing industrial and commercial work. In a domestic situation, if there is ever a reason to use a 10A, it's probably a good enough reason to provide an extra circuit.

 

[demkap]

harsh mate i only wanted advice! i am competent in electrics i just havent done certain things yet like that.. i know how to work out fuse rating for say the heater but i jsut wanted to calculation for the cable size id personally go for a 10mm cable for that 9.6kw shower. also with the smoke detector i just wondered if your aloud to run if off another supply say a fused spur? i have it on its own circuit anyway im just asking the question, thats what this site is for is it not!?

 

[Baker1988]

Personally i would use 10 mm for the shower and it is best to have thd fire alarm on its own circuit as it is a safety circuit but it use to say in some places that you can take a feed off a lighting circuit for fire alarm but not sure if that has changed