DIY Doctor UK DIY Forums

Hi

Im trying to change the tranformers above two spot lights which I assume have gone as new bulbs aren't working.

I've not done it before but figure I can give it a go with advice online. And I do know to shut down the power to that ring, and will be investing in a volt stick.

But I've fallen at the first hurdle because I can't open it. It seems to be sealed, possible glued, no visible screws. Cant prise it open with a stanley knife, have tried pulling it apart with mole grip and pliers.

Am I missing something obvious. Or do I have to crack it open?

Any thoughts gratefully received

The transformer as you call it has no user parts and is replaced as a complete unit. Often called electronic transformers they are really switch mode power supplies. These often have a 35 kHz output not the 50 Hz expected from a true transformer and also a minimum and well as maximum output.

The one you have I think comes complete with cables. If cable from electronic transformer to lamp is to long it can cause EMC problems so sealing cable into unit ensures placed near to lamp.

Today rather old hat. The GU10 version of MR16 lamps does not need a transformer and can take tungsten, cold cathode and LED bulbs and the advantage of having SELV (separated extra low voltage) has been lost.

The holders of the GU5.3 were forever failing and because 10W ~ 60W the electronic transformer will not power 5W LED lamps. Also cold cathode will simply not work on 12 volt.

Since you have to remove cables at junction box and route new cables to light may as well fit a GU10 lamp and have done with it.

thank you

realised i needed to pull down the junction box too and then it clicked i just needed to buy a prewired transformer.

All working now but thanks for the advice re GU10 lamps