2 halogen spotlights out of 10 not working when dimmer switch turned on?

Thanks Sheepdog,

All 10 lamps/spotlights are 50W and same wattage, 240V.
Funnily enough, I have 4 more ceiling spotlights in the downstairs hallway without a dimmer switch and now when turned on, 3 of them come on fully and 1 comes on dim before it turns itself off after a few minutes, every time ! teansformer on it's way out?

Back to the lounge ceiling lights, I've replaced the actual dimmer switch twice previously (prior to the light not working at all) where I've gone to turn on the lights and a sudden sound of a blowout occurred in the dimmer switch causing the fuse box to trip. By replacing the dimmer switch has resolved the issue and the lights where working fine then. Never had any buzzing sounds coming from the swtich itself. So now currently, the buzz is coming from the ceiling (assume it's the trasnformers) when lights are turned low so guess I just need to replace the affected ones but will probably get somone in to advise/confirm. Thanks.

Roger
March 2011

The boxes could be transformers, IF they are low voltage lamps. GU does not say much, that is the type of fitting. the box could also be a connector unit. Are they all the same voltage rating lamps? the buzzing could be the dimmer itself, It may not be rated correctly, depends on who installed them. You need to check all lamps are same voltage and same wattage. You then need to check, if the dimmer is upto the job. After switching off at the mains box, if you carefully unscrew the dimmer, it should say on the back somewhere the rating, some give as wattage some as amperes. IF amps, TOTAL wattage, divided by voltage gives you the amps.
A lot of low voltage units, cannot be dimmed. Depends on the dimmer and transformer/s, they have to be correct. If that fails, get some one in

Sheepdog
March 2011