tempremental down lights

[simonatlondon]

Hi everyone,

i've got this problem. 4 downlights 12v on 1 switch. 2 of them only, go out and come back on every now and again. I thought it was just dodgy connections in the jb and so i redid them on the 2 downlights that are faulty. I turned the lights back on and they came on as normal. Left them on for a couple of minutes and the same thing keeps happening. also sometimes when i switch them off then on again the faulty lights come back on again.

The sparky who installed them used 2 core flex as the switch line for some reason and not twin and earth. So theres no earth in the run either.

If anyone has had any experience with these problems then please let me know how you sorted it out.

Much appreciated.

p.s. One of the transformers has a brown mark the size of a 2 pound coin on its side which looks like burning.

 

[wayne]

hi, sure someone else will spread more light on this but 12v sounds like the tx's cheap ones are known to fail also are they big enough?(va rating)

 

[Cirrus]

Yeah, transformers sound like they are on the blink maybe.

 

[Spudmiester]

would agree with crap transformers. Sounds like overheating, is the ceiling void full of fibreglass, and are the transformers virtually buried in the stuff

 

[simonatlondon]

Thats what gets me, there is no insulation at all. So why would they get too hot and cut-out? Is the internal stat kicking in too early because its just not working at it intended threshold?

 

[MacSparky]

I would definately change the tx with the burn stain, maybe shorting between the windings inside it

 

[The Electrical Connection]

check the rating of the transformer
check the rating of the lamp/s it powers
Are they within range ?
are the transformers electronic or torroidal?
are the transformers auto resettable ?

The answer to at least 1 of the above will tell me what the problem is.

Look forward to your reply.

Z.