A Quick Question about Halogen to LED conversion

[Lancs Lad]

I don't really want to replace the whole installation.

Just the bulb - when it eventually fails!

That's not unreasonable, is it?

[AC/HL]

No need to replace the installation. In hindsight, if you'd attached the image in post 25 to post 1, things would have been easier. You just need an MR16 LED to replace the MR16 Halogen when it fails.

Why not bypass the transformer and use a mains rated bulb?

[Lancs Lad]

Thanks, Bill.

I'll do that.

It's been an interesting thread, though, hasn't it!

[cheerfulcharlie]

Originally Posted by Scimitar

There's an echo in here!

Apologies to you Scimitar you already covered it and I didn't see it.
I don't really see a future for the MR16 in the home but perhaps a specialist application.

[Glowing Bits!]

If Peter has no use for the tranny, please do send it this way, TDC make very good trannies.
Rick.

[Lancs Lad]

I still haven't decided on a dichroic bulb for the downlighter outside, but I bought these (see pic) today as replacements for other 12 volt halogen capsule bulbs under the kitchen cupboards.

They haven't gone pop yet, but they must surely be getting near! They've been working for ten years. Will these ones I've bought be the right ones, do you think?

Thanks for all thoughts

[Lancs Lad]

The undercupboard 20 watt, 12 volt halogen lights have suddenly stopped working, and, after changing the fuse in the FCU, I can only deduce that the GET electronic transformer has failed.

I've bought a set of those triangular/pyramid shaped, 240 volt LED downlighters as a replacement solution, but I'm loath to change them in case the light isn't as bright.

I rely on really bright lighting to put my contact lenses in properly. Yes! I know it's a daft reason, but it is how it is.

Should I keep the halogens and fit a new transformer? Or risk going with these new-fangled LEDs?

[winston_1]

There seems to be confusion here over terminology.
MR16 means multifaceted reflector 16 eights of an inch in diameter. It has nothing to do with the voltage or base of the lamp. Most 240v GU10 lamps are in fact MR16. Some LED lamps are the same size but don't have the multifaceted reflector. Manufacturers/sellers are to blame as they seem to refer to GU5.3 12v lamps as MR16 (which they are of course) but that is not the definition of MR16.

Electronic transformer. No such thing but again blame the sellers for misdescribing a switch mode power supply. A transformer is a device which changes voltage or current using electromagnetic induction. Isolating transformers work the same way but do not change the voltage.

[TrevorG3VLF]

But a mains switch mode power supply is an electronic transformer. It contains electronics and a transformer.

[Herald1360]

A mains SMPSU may or may not contain a transformer- it will need an energy storage device, usually but not necessarily an inductor. If the output is isolated from the mains there will almost certainly be a transformer though it could be done using a flying capacitor technique.

I'm not convinced that a "transformer" must use magnetic induction, isn't it literally just a device for transforming something from one form to another?

[AC/HL]

If you Google MR16 it can have any base, and be any voltage, but in popular usage it's normally 2 pin 12 volt. Similarly the power converter is universally called an electronic transformer. Using any other name, except in present company perhaps, will likely get the response "oh you mean an electronic transformer"

[Brigham]

'Transformer' in electronics industry jargon generally means a device with two or more coils, inductively linked.
In the tramway industry, a 'rotary' (more jargon) is a type of transformer.
There's also some sort of kids' toy...

[Lancs Lad]

This is the transformer for the kitchen cupboard lights.

I only called it 'electronic' because of the labelling! It's really lightweight - nothing like the heavy 'bricks' I've used previously.

Do they generally just fail without warning? It's had fairly heavy use for at least ten years.

[AC/HL]

I can't help thinking that titling the thread "a quick question" was rather tempting fate!

[Hartley118]

.........it was only supposed to be about a lamp replacement............

How many vintage radio enthusiasts does it take to change a light bulb?...........

Martin

[broadgage]

Originally Posted by Lancs Lad

This is the transformer for the kitchen cupboard lights.

I only called it 'electronic' because of the labelling! It's really lightweight - nothing like the heavy 'bricks' I've used previously.

Do they generally just fail without warning? It's had fairly heavy use for at least ten years.

Yes they do fail without warning, this seems to be random and not age or use related.
And yes the almost universally accepted term for these is "electronic transformer" They have an AC output at a very high frequency.

[Lancs Lad]

Finally got it sorted 🙂

Took delivery of these bulbs today, and everything is working fine.

[Lancs Lad]

Sorry if I'm being annoying, but can I ask another question?

I currently (sorry! NPI!) have a 20 watt, 12 volt halogen spotlight over a worktop in my kitchen.

Would anything catastrophic happen if I replaced the bulb with this new 5watt LED bulb?

Do transformers adjust to how much power they are asked to supply? I don't want it to get 'sort of constipated' because the lamp doesn't need the full wattage it is designed to supply!

[winston_1]

That actually looks like a transformer rather than a switch mode power supply. It will be perfectly OK. A transformer will only supply the power required.

Think what would happen if those big transformers at sub stations force their max power output to peoples homes.