Replacing a lighting transformer

Zither

Hello! My halogen (yes, I know...) bathroom lights have stopped working so I'm going to replace the transformer to see if that works first.

Apologies for the quality of this pic but this is the current transformer wired in.



This is the new transformer that I've bought.



I appreciate that brown wire input is live (L) and blue wire input is neutral (N) but what does the output symbol (circle with x in it with 1/2 square boxes) on the transformer mean? Does it mean that it doesn't matter which terminals the wires to the light go into on the output?

Thanks!

keith969

Circle with X in represents the light. It doesn't matter which way round the 12V lighting circuit goes, and it would appear that it supports up to 4 lights.

Personally I'd get rid of the transformer and wire in 240V GU10 bulbs instead. The 12V side of the transformer is high current and the number of times I've seen the transformer partially melted due to a poor (high resistance) connection... also no transformer means one less thing to fail.

grumbler

Replace halogen lights gradually with LEDs, and the current will be much lower. And the transformer will heat much less - often it's some unresetable temperature fuse that trips because of overheating, especially if the transformer is hidden somewhere and lacks air circulation around it.


https://www.screwfix.com/p/lap-g4-capsule-led-light-bulb-180lm-1-8w-12v-4-pack/744fh


You can buy cheaper from gearbest.com and similar

Zither

keith969 wrote: »

Circle with X in represents the light. It doesn't matter which way round the 12V lighting circuit goes, and it would appear that it supports up to 4 lights.

Personally I'd get rid of the transformer and wire in 240V GU10 bulbs instead. The 12V side of the transformer is high current and the number of times I've seen the transformer partially melted due to a poor (high resistance) connection... also no transformer means one less thing to fail.

Hi Keith,

Nice one thanks.

Yes, the transformer has 4 outputs but the bathroom lights are actually pre-wired into a splitter so i only need to use 1 output on the transformer to the splitter if that makes sense?

So I'll just wire in brown to live and blue to neutral and wire out the two wires to the lights on using the first two output terminals.

Yeah I've seen a melted transformer before - i didn't know what the cause though.

I was actually thinking of getting them replaced with LEDs but thought I'd do like for like right now just to get it sorted.

Thanks!

Zither

grumbler wrote: »

Replace halogen lights gradually with LEDs, and the current will be much lower. And the transformer will heat much less - often it's some unresetable temperature fuse that trips because of overheating, especially if the transformer is hidden somewhere and lacks air circulation around it.


https://www.screwfix.com/p/lap-g4-capsule-led-light-bulb-180lm-1-8w-12v-4-pack/744fh


You can buy cheaper from gearbest.com and similar

Hi Grumbler,

Thanks - Yeah I've been wanting to do this for a while - was toying with getting an electrician to swap them to LED but he quoted me £150 which seemed a bit high!

Not sure why bathroom lights have stopped working - loft is actually freezing at the mo now winter is starting to set in.

Bathroom lights are MR16 - can I just replace MR16 bulbs for the ones you've linked to without changing the transformer again? If so, is there a version of those bulb that I can use that look more like the tranditional MR16/GU10 shape - so they fit the existing light fittings?

Thanks!

keith969

Not sure what you mean by splitter, if more than 1 light is run off a single output of the transformer you may well overload it.

I had transformers on all my downlights when I moved in, several transformers had gone, slowly I replaced them all with 240V LEDs (like these: https://www.screwfix.com/p/enlite-e8cx-fixed-fire-rated-led-downlight-without-bezel-580-620lm-8w-220-240v/3631x).

Zither

keith969 wrote: »

Not sure what you mean by splitter, if more than 1 light is run off a single output of the transformer you may well overload it.

I had transformers on all my downlights when I moved in, several transformers had gone, slowly I replaced them all with 240V LEDs (like these: https://www.screwfix.com/p/enlite-e8cx-fixed-fire-rated-led-downlight-without-bezel-580-620lm-8w-220-240v/3631x).

Hi Keith,

Yes, that's exactly it - 4 lights are currently run off a single ouput. Probably explains why it overloaded then! It was already wired that way before I moved in to this house.

The lights you've linked to look good - expensive though per light? What do people use when they wire in 'standard gu10 leds' to replace halogens - do they use a LED specific transformer?

Thanks!

keith969

For some reason quoting is broken at the moment, at least for me...

Yes those LEDs aren't cheap, but they include both the holder itself and the LED bulb (which I don't think you can change). They run off 240v so no transformer. Mine have been in for a couple of years with no failures.

GU10 LEDs run off 240v so no transformer needed, but you will have to change the holder if yours are currently 12V.

Zither

keith969 wrote: »

For some reason quoting is broken at the moment, at least for me...

Yes those LEDs aren't cheap, but they include both the holder itself and the LED bulb (which I don't think you can change). They run off 240v so no transformer. Mine have been in for a couple of years with no failures.

GU10 LEDs run off 240v so no transformer needed, but you will have to change the holder if yours are currently 12V.

Nice one thanks. think I'll give replacing the transformer as it is a go and then if that doesn't work I'll look to replace them with LEDs - maybe yours - I like how you can change the colour temperature of them - keep an eye out for a post from me on this forum if i do haha!

Thanks for your help.

ianto11

Hi,

Not sure if your still thinking of changing to LED's but These are the mains voltage equivalent of MR16
Do away with the transformer and happy days