Replacing recessed ceiling lights - wiring question.

[shaky1105]

Been asked by a neighbour if I could do this for her. She wants to replace 8 20W Halogens with another model of fitting, also rated at 20W. When I had a look at the existing installation I noticed that each separate light has been wired to a Multi-Way Junction Block ( via 0.75mm Flex ) then to an existing ceiling rose via 1mm T&E ( I presume for the old original single light fitting in the room )

Wouldn't it have been better to "Daisy Chain" the lights with T&E from the rose, finishing at the end light like a radial cct ? The only reason I ask is that the few installations I have seen have normally been done via the "Daisy Chain" method.

Would it be OK to leave the existing wiring in situ or would it be better to re-wire as a radial set-up, in which case, would this prevent me from doing the job for her as it would involve altering the wiring ?

This is all in the front room of her house btw.

Thanks for your help.

 

[Taylortwocities]

No it would not be better.

BTW, you did not mention a transformer, is this a 12v (ELV) set up??

Think about ohms law.

There would be 8 * 20 watts at 12v running along the .75mm² wire. That is more than 13amps.

.75mm² may (just) carry 13A but think about the volt drop. The lamps will get dimmer as you get to the end of the daisy chain.

So the existing setup is better.

 

[shaky1105]

Thanks for the reply TTC. The existing lights are 240v and the ones they are being replaced with are 240v also.

However, even though this is a lot less current to deal with than elv lights, I will leave the existing setup and just change the fittings for her.

Thanks.