Joining 1.0mm lighting cable to 1.5mm cable

[Berkleyboy]

Can anyone help please I have an existing 1.0mm lighting circuit in kitchen and am adding some 50watt downlighters. Two questions:

1. The new lights say use 1.0mm cable only. Would there be a problem using 1.5mm?

2. To do the above I have to extend the circuit - I already have 1.5mm cable, would joining it to the current 1.0mm feed cable be an issue concerning the integrity of the circuit or regulations?

 

[kai]

On a B6, 6amp breaker, you can safety use 1.0.mm or 1.5.mm cable, as long as the voltage drop and earth fault resistance tests are met, which are unlikely to be a problem unless you live in a very big house etc.
On a B10, 10amp breaker, you should only use 1.5.mm cable throughout.

 

[ColJack]

to answer both..
putting in larger cable isn't a problem in the electrical sense.. it's ok to go bigger than you need, but not smaller..
practically though it may be a problem if the terminals you are connecting to are not designed to take bigger than the recomended size ( maybe on 12V downlighter transformers for example.. )

however.. the adition of downlighters to a circuit in a kitchen is notifiable to the LABC under Part P of the building regulations..

the also look naff.. ( please note this is personal opinion although many sparkies will agree.. )

 

[spark1]

The new lights say use 1.0mm cable only

The only reason I can think of if the manufacturers limit you to 1.0mm cable would be if their connections only allowed that max size, other than that I think Kai has given you the correct answer

 

[Berkleyboy]

Thanks - Although have done many DIY wiring jobs in the past, I think I will get a sparks to come and do it to be sure after the event of the new regs etc.

As for the downlighters, she that must be obeyed wants them and if I thought they were hidious, I would have been brave enough and foolishly attempted to pursuade her otherwise!

 

[spark1]

My apologies ColJack.. I posted after you with some similar advice

 

[ColJack]

My apologies ColJack.. I posted after you with some similar advice

no need to apologise.. the more answers the better.. and if they happen to agree with my answer, even better..

 

[Berkleyboy]

Kai

Many thanks. Not a big house and total wattage for all lights on this circuit is approx 800watts, if all on at once. I believe that max is for any one circuit is the rquivilant to 11 x 100watts lights, if I have read this correctly?