12v E27 Lightbulbs

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We have some in wall LED lights which have seen better days and we want to remove them. Ideally we want to fit some bulkhead lights that take E27 Edison Screw bulbs and surface mount them as they will go with the vintage look we are after in the hallway.

The current lights obviously have some sort of transformer or driver somewhere and are 12v. I have tried opening the wall above one of the fittings but I have a feeling the transformer is buried somewhere in the ceiling as I can only see capped cable above the fittings so far.

My question is can I fit the new fittings and get a low voltage 12v E27 bulb that would work with the current feed? They are only low level accent lights so wouldn't matter if not bright - we have ceiling lights for that. I have tried searching online but it all looks a bit of a minefield as to what might / would / definitely not work!

If not any other suggestions? I was toying with keeping the LED sections of the old fittings and somehow fixing them within the new fittings, but then I need to diffuse them and all sorts!

Many Thanks
 
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Pictures of your proposed fitting woud allow us to come up with ideas.
 
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Ah I see - yes I can do that - it's kind of what I was considering with replacing the innards of the new ones with those of the old - diffusion of the light was the biggest issue with that. So if I can get a diffused bulb with a different holder that would work - if the current transformer / driver will work that is? It reckons it can power up to 6 of the fitting we have, which suggest there is only the one transformer as that is how many fitting we have.
 
Looked at the link, says 10 volt in writing and shows a 24 volt unit, what one needs to be careful with is it may be a driver rather than a simple fixed voltage power supply, LED's are current dependent, but most LED packages include a driver which makes them voltage dependent.

The lighting industry seems to mix and match names, so having transformer, driver or other name on the device means nothing, your link shows
upload_2022-5-14_11-34-58.png
which clearly is not 10 volt.
Requires 10v DC Transformer, Product Code 1807 (See related products)
Says very little, we would not normally label a DC power supply as a "Transformer" may be a driver, but I would suggest you need to find the actual unit before changing any thing, or at least put a meter on the supply, and see if AC, DC, and what voltage, and if the voltage varies with and without load.
 
I suppose "Led supplier" is an interesting variant of "LED Driver", and certainly isn't "transformer" :)

I wonder what those figures mean - is it saying that it can produce only 20W at 24V DC with a 90V AC supply, but can supply 25W (at 24V DC) if the supply is at least 150V AC?

Kind Regards, John
 
I have certainly come across SMPSUs before that have a higher power rating at the upper end of their voltage range, it makes sense as the currents in the primary side will be lower and the primary capacitors will be able to store more energy.
 
I have certainly come across SMPSUs before that have a higher power rating at the upper end of their voltage range, it makes sense as the currents in the primary side will be lower and the primary capacitors will be able to store more energy.
Yes, as you say, it makes sense. I only commented because I could recall having seen that before - but iut siounds as if you have!

Kind Regards, John
 
It would seem something lost in translation. And yes seen the debate before with LAP top power supplies where a trolley with LAP tops was used by the school and all charged from one 13 amp outlet, charge rate was some thing like 1 amp at 24 volt, so 0.1 amp at 240 volt, but because designed for 100 - 250 volt the input was rated far higher, so rated around 500 mA each, so 30 in a trolley was in theory an over load.

But my point is more the advert has an error some where, and a white LED is around 3 volt, so three in series around 9-10 volt so a current regulated driver at 10 volt maximum would seem logical, instead of the more common 12 volt and a resistor to limit current, but it simply does not all add up.
 
... But my point is more the advert has an error some where, and a white LED is around 3 volt, so three in series around 9-10 volt so a current regulated driver at 10 volt maximum would seem logical, instead of the more common 12 volt and a resistor to limit current, but it simply does not all add up.
This, which you posted ...
upload_2022-5-14_18-4-43.png

... would seem to suggest that it isn't a constant-current driver it needs, doesn't it?

Kind Regards, John
 
Thanks all. I have a new multimeter arriving in a day or two so will test the output at the fitting points. I did get a 12v LED bulb tonight and tested in one (it arrived before the meter) and that illuminated fine, but I appreciate loading up 6 of those is a different kettle of fish. What am I looking for in terms of output voltage to see if it would run 6 (it ran 6 of the old fittings of course)? Check if the voltage drops every time I add an extra bulb? I am still toying with the idea of a transplant of the old innards into the new fittings if I can't be sure it'll be OK.

Worst case am I likely to burn the place down or just make the transformer / driver go pop and trip the consumer unit?
 

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