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[Hawaiianrobot]

Hi,

Please excuse me if this is a very basic question.

I've been attempting to replace some MR16 dimmable Halogen lights (Sylvania Coolfit) in a 12V 50W max GX5.3 Coolfit 50 ceiling recess with led lights.

I tried some GU5.3 12V led bulbs and they didn't work, and having put the Sylvania bulbs back, they don't work either now.

Before I call an electrician out, have I just picked the wrong bulbs or has something blown?

I would prefer to not have to get specialist/hard to find bulbs, if there's no real benefit.

Is it straightforward switching the fittings to a GU5.3 fitting, if that's the issue?

Many thanks!
Sam

[Mr White]

Without being there to check it is not possible to say "Do this and all will be well"

I would suggest you put 50% of the original lamps back, leave the other lamps out, switch on and see what happens.

A picture of the light may help, also how much did this light cost?

[Hawaiianrobot]

I took out 50% of the original bulbs and it's still not working. Very odd.

Is it a big job to replace the fittings (and transformers) with something like GU10?

Many thanks

[Mr White]

Are you saying that you are just changing a lot of recessed down lights?
Picture would still help.

[ericmark]

G5.3 refers to pin spacing, GX53 is very different it is a 230 volt 5 inch surface mount down lighter, MR16 is the size and type of reflector could be G5.3, GU10, or SES.

I will guess you have a switch mode power supply likely marked 20 - 60 VA and the bulbs fitted are under 20 VA so it has turned itself off.

As to why it did not reset no idea, however the holders for the G5.3 pins don't seem to stand the heat, and many times I have needed to change holders once disturbed.

If you have access to the mains supply then GU10 is far better, personally I think ceiling recessed spots look like a planetarium, and are useless for lighting a room, but if you like them, well the cost of 16 x 3W to one 24 W strip light is not worth worrying about.

However with 50W quartz you simply can't get LED that bright at 2 inch across, the LED if that bright needs cooling so no longer 2 inch as there are cooling fins, so a ceiling which had 9 quartz lamps likely needs 16 LED to get same amount of light, you can get 5 watt which fills the 2 inches, but not much more, it claims 50 W quartz = 6 W LED but it does not seem to work out.

So you need to consider next move. And although GU10 is likely easy way out, it depends how easy you can access the transformer. Remember no good putting a meter on the socket, as not enough load to switch the power supply back on.

They call the power supply an electronic transformer, for LED this likely needs replacing for a toroidal transformer or a driver. The driver should be current regulated but there are also voltage regulated and you want the voltage regulated, however I think also likely you need new bulb holders, so if you can go to GU10.