LED Under Cupboard Lights

[DerbyBorn]

My daughter has a house that has IKEA lights under her kitchen cupboards. They take 12volt 20 watt G4 bulbs.

Could I directly replace the fittings with LED fittings?

[Tim Watts]

Check the PSU is happy to supply a much reduced load (counter intuitive I know).

[DerbyBorn]

Tim Watts wrote in news: [e-mail]:

Will the data label have a min?

[Adrian]

There's plenty of 12v G4 LEDs about, just a straight swap for the existing bulbs.

[ARW]

That is only half the answer.

As they are G4 lamps then a DC LED driver will almost certainly be needed. If the OP can find AC LED G4s than you are correct.

Screwfix claim to be selling 240V G4 LEDs but I think that they are talking bollocks.

[Tim Watts]

Sometimes :)

[Tim Watts]

I was wondering to say that, but G4's don't have any way to force polarity, do they? I assumed they must have a bridge rectifier built in or similar circuit to compensate. But it's a good point even if that's the case as AC's going to flicker - and the G4 LEDs I've seen have recommended replacing the PSU with an LED friendly one.

:)

[Chris J Dixon]

Indeed, but there are at least a couple of potential problems, which I have discovered when trying to do a swap for the lights in my extractor hood.

I went for a disc type, which nearly fitted, except that the dimensions had omitted any details of the components on the back of the board, and a capacitor stuck up inconveniently. Pressing on, the first lamp worked OK, in parallel with an existing halogen, but when both LED lamps were in place, the supply was clearly not happy and they flickered. Another one down to experience. :-(

Chris

[Rob Graham]

The COB disc type I got with G4 connection was polarity sensitive - ie it didn't work one way, but the other. As it too was for under-cupboard and the correct 'other' had it pointing up the way (!), I had to change over the polarity of the leads. Rob

[Andrew Gabriel]

12V halogen supplies often have a lower power limit, e.g. 20W-60W. This is because they have no voltage regulation, so to ensure the output remains within an acceptable voltage range, they check the power output is in a known acceptable range. Sometimes leaving one halogen in will meet the minimum power requirements, but changing to a regulated LED driver will be better.

[Andrew Gabriel]

Kosnic did some really good one-sided g4 capsule replacements (multi-LED, AC, 2W, wide angle, indistinguishable from the capsule LEDs when mixed in a row of fittings), but they sadly stopped making them. I believe Verbatim still makes one (single LED) and Maplin did stock it a while back. I suspect it may not be wide angle, so check first or you might end up with a small bright circle of light on the worktop just under each light.

There are capsule replacements which emit light in all directions, but you will probably lose over half the light if you put them in a fitting with a reflector to direct the light in one direction. I have some Integral ones from CPC which work OK (and again are AC), but they're in a fitting which needs light emitted in all directions.

Watch out for the LED's colour temperature. There are many at 5000K and upwards, but you probably want something more in the 2700K-3500K, depending on the rest of the lighting in the room. (5000K+ is particularly bad for kitchens where any meat preparation takes place.)

[DerbyBorn]

Can you point me to a trypical sort of LED Driver. I have no understanding of LED requirments.

[Tim Watts]

As you see, there's not really much of a standard - you need to get one to suit what you are driving.

Constant voltage seem the more common type. And I suspect 12V would be the more prevelant, but I don;t know for sure.

There's also constant current - but those seem to be very keyed to the specific LEDs you are using (which is what you'd expect).

[News]

When I first mentioned (here) switching to LEDs, I was pointed to LED Hut, and was pleased with the result. I too am looking at under cupboard lights, and, not having a clue about such things, will just buy a kit from LED Hut. Perhaps more expensive than buying individual components from eBay, but with a kit, at least I'll know I've got matching items that should work out of the box.

[ARW]

And you know to save money when buying from them?

Tell them you are trade, sign up as trade and they ask no questions.

[News]

In message , ARW writes

Excellent. Thanks, Adam.

[spuorgelgoog]

Except that buying as a trade buyer means you lose the protection of buying under a consumer contract.

Owain