Halogen downlights keep turning off and on

[Mattie]

Hi all,

Just wondering if you could help me out?

I made the mistake a few years ago of getting halogen lights installed throughout my house. Everything seemed fine for a while but over the years each room has generated problems.

Bedroom 1: After a while 3 of the 6 lights would turn off then come back on every now and then. Now only one works.

Bedroom 2: Same problem.

Bathroom: The bathroom was next to start playing up although the lights are on most of the time but do turn off quite a lot. Again, when they do go, only 1 light stays on.

Lounge: There's a double dimmer switch. One switch controls 2 lights and never seems to be a problem. The other controls 6 lights, 3 of which will turn offf and on randomly (it's happened twice as i'm writing this!)

All the rooms have dimmer switches.

The guy that did the work has emigrated so it's left me wondering what to do about it. Do you think it could be just the transformers failing? (they're all Kingsway 60v boxes) or does this sound like a more serious wiring issue? I'm worried that this is going to cost me a fortune to get put right.

Any help would be really appreciated.

Thanks for reading.

 

[micknew]

Its the dimmers or the transformers, in that order I think.
Second thoughts must be the transformers.

 

[Marvo]

We have endless problems with the ceramic plug connectors on the SELV lighting to the point now where we replace the ceramic 'holder' as a matter of course when we replace halogen lamps.

The other thing that springs to mind is have you had any insulation installed? If the transformers got buried they could be overheating and cycling on their thermal protection.

 

[CrazyScozzese]

I would expect that where half the lights go off, if on the same dimmer, then it is probably the transformer. Where they all go out at the same time, it could be either. If the transformers are prime suspects in one room under that scenario then the finger would point there in others.

I have MK dimmers that have the seperate on/off switch to the dimmer rotary, and they are prone to wandering up and down.

I have 14 yr old transformers, top quality, but they are prone to dry joints on the output side which cause a similar appearing wandering fault.

One day I will change them all, so my wife tells me.

 

[telectrix]

it wouldn't cost a lot to spend an hour seeing what the problems are. any self-respecting electrician would be able to give you a diagnosis and quote without costing you an arm and a leg. if you post your location ( just the area), a member may be close to you.

 

[needasparks]

Have seen this many times with transformers placed too close to the fittings, the internal thermal trip operates until it cools down then comes on again. may be as simple as just pushing further away from heat from lamps. Obviously this would only affect the light on that transformer so if they were a kit or multible lights fed from one transformer and be why a bank of lights goes out or could be a loose conection feeding downstream units.

 

[GLENNSPARK]

i reckon what they have done is used 1 tranny to run a load of lamps off......just joint boxed...like fed a joint box of ov 1 tranny then radiated it out to a load of lamps and overloading it.......the trannys thermal cutout is kicking in here...hence this "on and off thing".......

 

[Mattie]

Thanks for all the suggestions!

I'm going up in the loft today to check how it's all been done. Now I know what i'm looking for it should make life a lot easier.

The other thing that springs to mind is have you had any insulation installed? If the transformers got buried they could be overheating and cycling on their thermal protection.

The insulation goes round the fittings so there's plenty of air circulation. I bought some Aico thermal caps so I could insulate over the top of them (wasn't expecting them to be so massive though :/ )

it wouldn't cost a lot to spend an hour seeing what the problems are. any self-respecting electrician would be able to give you a diagnosis and quote without costing you an arm and a leg. if you post your location ( just the area), a member may be close to you.

I've bought a couple of new transformers to see if that will solve anything. If I don't have any luck then i'll see if anyone here would mind getting involved. I live in Chelmsford, so let me know if you're local.

Thanks again - I really appreciate the help.

 

[Kakys2]

You could try replacing the lamps with led lamps, this would lower the load and the transformers wouldn't get as hot, the lamps are expensive though but they are supposed to last for ever and they use less power so cheaper to run. Also less of a fire risk.