12v kitchen lighting

[greenrook]

Good morning all. Our kitchen lighting is comprised of 6 12 volt ceiling spotlights. Just lately, it sometimes happens that 3 of them will go out (always the same 3) and sometimes they all go out. After a time, it's possible to switch them on again, almost as if something had been allowed to cool down. We have been replacing the little halogen 20 watt bulbs, when they failed, with 50 watt ones, is that the problem? Or is the transformer wonky, wherever it is? The kitchen is a flat-roofed extension to our bungalow, so presumably the transformer will be somewhere in the main loft? I'll be grateful for any enlightenment - g

[heathfield]

Often the transformers for such lights have a stated load capacity. Installation instructions will say the number and wattage of bulbs to be used. Under-rating or over-rating the transformer can lead to problems. You've more than doubled the load by using 50w bulbs. It sounds like a thermal trip on an overheating transformer is operating, and switching off the supply. It's allowing you to switch on again once it's cooled down.

[bazwillrun]

you've answered your own question

50W !!!! I'm suprised it still works at all

[greenrook]

I thank you both for your timely help. I will replace all the bulbs with those of the proper wattage and be more careful in future - g