12v Mini Downlights Basic Question

[GreenGilbert]

Hi, Hope someone can help with a no doubt very basic question?

I have 9 x "Emcalite" Mini Downlights (12v 20W - G5.3 bulbs) installed in my Living Room ceiling. Pretty sure they are Halogen.......basically all are discoloured so need replacing.

Looking to replace them with something similar to these : https://www.tlc-direct.co.uk/Products/FLLV1350C.html

I've pulled out 4 or 5 of them, and can't "find" (feeling around in the ceiling void) any transformers.........is this because Transformers are only needed on LED versions of these lights?

I don't think I can physically get any transformers pushed through the existing holes......but would like to replace them with something similar (don't want to have to cut new holes)....

Any advice would be appreciated.

 

[ban-all-sheds]

is this because Transformers are only needed on LED versions of these lights?

No:

I have 9 x "Emcalite" Mini Downlights (12v .....

I don't think I can physically get any transformers pushed through the existing holes......but would like to replace them with something similar (don't want to have to cut new holes)....

If you replace 20W halogen lights with 20W halogen lights why can't you re-use the existing power supplies?

 

[ericmark]

12 volt lights can have a number of devices to power them,

these toroidal lighting transformers were the original method and these will power both LED and quartz lamps but did not have built in regulation and were heavy and expensive, so then came the switched mode power supply called an electronic transformer as it replaces the old heavy lump, however these have in the main a minimum output as will as maximum output and a frequency in the kHz range better for quartz as regulated but not suitable for LED. So since the base LED is DC having a switch mode unit with DC output will drive LED lamps with a simple resistor used as a driver, so you also now get these DC power supplies I find it very confusing as many have the label driver where really they are not, a driver is a current regulated device.

Until you find what you have all you can do is replace like for like so remove a 20W quartz and replace it with 20W quartz, however any quartz lamp can shatter allowing white hot bit of quartz to fall from it, so the light you link to with a quartz lamp should only be used where the floor is non flammable and also there is the same rays from quartz lamps as the sun, so if close to animals including human it should have a glass window to stop UV light and catch any bits, as with the MR16 lamps.

 

[winston1]

They don't have to have individual transformers. It could well be there is one 200 watt transformer somewhere.

 

[GreenGilbert]

No:






If you replace 20W halogen lights with 20W halogen lights why can't you re-use the existing power supplies?

Hi ban-all-sheds, Thanks for the reply.

Sorry, I probably didn't make myself clear. Basically I can't "find" anything attached to the wires that I have pulled back.........as in no power supply at all. The wires go from the "bulb holder" of the lamp into the ceiling (as you would expect), but I can only pull back maybe a few inches of cable which then becomes taut. If I stick my finger into the recess of the ceiling, then I can't feel any transformer/power supply at all......just more flex heading off to (presumably) the next lamp.......?

 

[GreenGilbert]

12 volt lights can have a number of devices to power them,

these toroidal lighting transformers were the original method and these will power both LED and quartz lamps but did not have built in regulation and were heavy and expensive, so then came the switched mode power supply called an electronic transformer as it replaces the old heavy lump, however these have in the main a minimum output as will as maximum output and a frequency in the kHz range better for quartz as regulated but not suitable for LED. So since the base LED is DC having a switch mode unit with DC output will drive LED lamps with a simple resistor used as a driver, so you also now get these DC power supplies I find it very confusing as many have the label driver where really they are not, a driver is a current regulated device.

Until you find what you have all you can do is replace like for like so remove a 20W quartz and replace it with 20W quartz, however any quartz lamp can shatter allowing white hot bit of quartz to fall from it, so the light you link to with a quartz lamp should only be used where the floor is non flammable and also there is the same rays from quartz lamps as the sun, so if close to animals including human it should have a glass window to stop UV light and catch any bits, as with the MR16 lamps.

Appreciate the comments on the Quartz lamps. Do have animals (cats), so definitely worth bearing in mind. Not found any transformers/power supplies of any sort yet.........

 

[GreenGilbert]

They don't have to have individual transformers. It could well be there is one 200 watt transformer somewhere.

That's what I was suspecting.......so if I replace them with the one's I linked to in my original post..........then presumably all would be OK? And if I DO replace ONE existing lamp with (for example) one of the one's in the link, then the worst case (I'm hoping) is that it just doesn't turn on that lamp?

 

[ban-all-sheds]

Basically I can't "find" anything attached to the wires that I have pulled back.........as in no power supply at all. The wires go from the "bulb holder" of the lamp into the ceiling (as you would expect), but I can only pull back maybe a few inches of cable which then becomes taut. If I stick my finger into the recess of the ceiling, then I can't feel any transformer/power supply at all......just more flex heading off to (presumably) the next lamp.......?

However they are supplied - be it 1 large supply or 9 small ones, if you replace the existing 12V 20W halogen lights with new 12V 20W halogen lights then you can reuse the supply/ies

 

[GreenGilbert]

However they are supplied - be it 1 large supply or 9 small ones, if you replace the existing 12V 20W halogen lights with new 12V 20W halogen lights then you can reuse the supply/ies

Thanks ban-all-sheds.

Sorry if this is an even more stupid question, but......If I'm replacing 12v 20w Halogen lights with 12v 20w LED lights, then do the same rules apply?

(the link I put in my first post is the lamps I was going to buy)

Thank you everyone who has replied so far.

 

[winston1]

Thanks ban-all-sheds.

Sorry if this is an even more stupid question, but......If I'm replacing 12v 20w Halogen lights with 12v 20w LED lights, then do the same rules apply?

(the link I put in my first post is the lamps I was going to buy)

Thank you everyone who has replied so far.

Almost certainly NO. 20 watt LEDs would be extremely bright. Perhaps you mean 20w equivalent light output.

LEDs basically require DC. The GU5.3 type however have built in circuitry to run on AC at mains frequency 50 or 60 Hz.

A transformer will provide this and will be OK. BUT usually transformers are not used. Instead switch mode power supplies or SMPS (often incorrectly called 'electronic transformers' even by sparks who should know better), and these are not suitable for LEDs as among other things the frequency of the output is often around 15,000 Hz or more. Also due to poor design most will not work at the low loads that LEDs are.

 

[ban-all-sheds]

often incorrectly called 'electronic transformers' even by sparks who should know better

That is what they are called Winston, therefore it cannot be incorrect to call them by what they are called.

ST*U about it.

 

[ban-all-sheds]

(the link I put in my first post is the lamps I was going to buy)

Looking to replace them with something similar to these : https://www.tlc-direct.co.uk/Products/FLLV1350C.html

That's halogen...

 

[GreenGilbert]

That's halogen...

In which case, that's great. A nice simple changeover. Thank you ban-all-sheds!

Appreciate everyone's help with this!

 

[ericmark]

That looks very dangerous, at least in a normal house, quartz can shatter and the bits are white hot.

 

[Echo the husky]

That looks very dangerous, at least in a normal house, quartz can shatter and the bits are white hot.

That makes it more fun.