Help appreciated with switching to LED downlights!

[Deadeye]

I've changed all the lights in the house to LED apart from the kitchen, which has halogen downlights currently.

I've been putting it off because I suspected it'd be a nightmare.

My first foray was to just put in some MR16 LEDs (6.1W each) into the existing low voltage tails. Mostly they don't light at all; one flickered sickly.
First question. My googling suggests that's because the transformers won't drive LEDs...or do I just need to find different MR16s?

Next step has been to remove a fitting and see what's above the ceiling. Bulb is pressed into tail; tail is wirded into mini connector box; other side of connector box wired to transformer; transformer wired to a bigger connector box that I've not had down but I think receives mains power. The bulbs are in three sets of six each; controlled on a 3-knob dimmer switch.

Second question. I think I should be able to contain the messing about to the transformer/bulb end of the equation and not have to change the dimmer switches?

Next the current transformers (I assume one per bulb?) are 240V AC to 12V AC T02 dimmable. There are lots of other data and symbols I don't understand.

Third question. There's a bewildering array of things purporting to be LED transformers. What do I need for 6.1W M16 bulbs?

Fourth question. Should I take the opportunity to change to GU10? If so, do I just wire the larger box to the GU10 lamp holder and throw away the existing transformers?

Finally, if I was switching to GU10, should I go integrated?

If the answer to 1-6 is "get an electrician" then they'll just stay as halogen, which is a shame.
Thanks in advance for your help

 

[Spectric]

These days LED MR16's are 230 volt and do not require the transformer. Are your existing bulbs 12 volt ?

not have to change the dimmer switches?

Not all LED's are dimmable and not all dimmers will drive LED's.

 

[Deadeye]

These days LED MR16's are 230 volt and do not require the transformer. Are your existing bulbs 12 volt ?


Not all LED's are dimmable and not all dimmers will drive LED's.

Yes 12v halogen currently. The trial M16 are dimmable

 

[Spectric]

Must say that these days GU10 is the normal LED bulb and the MR16 is not as common, as you know that has pins whilst the GU10 has T post. I got the MR16 mixed up because I see so few of them in use, they are 12 volt and not 230 volt as I said previous.

What cabling has been used from the transformer to the lights, because they were halogen then the cabling should be something like 2.5mm Csa as each bulb could pull 4 amps. You could then just dump the transformer and supply the lights at 230 volts and fit a smaller fuse.

 

[Myfordman]

Your halogen transformers are of a type that need a minimum load before they will switch on. They will have to be removed.

 

[John Brown]

Are they old skool transformers, or so-called "electronic transformers"? In my experience, the electronic variety can be fussy about loads. The downlights in my kitchen, if the bulb is removed, do not show anything sensible on DC or AC meter ranges, but work fine. I replaced about 30 halogens with LED at my previous tennis club, and they all worked perfectly, as there was a big old iron and copper wire transformer in the roof space, with multiple secondaries for better regulation.

 

[John Brown]

Myfordman type faster than me...

 

[Deadeye]

Thanks for engaging all!
The transformers are from 2009. They appear to be one per bulb (I haven't had all the fittings off).
They're 240V to 12V 60VA (I assume = W?)
We have 40W halogen bulbs in. I wan to replace with 6W LED

 

[johnny]

I recently did the exact same thing but I took the opportunity to get rid of all the transformers and switched to using GU10 with the 230v lighting ring in both the kitchen and bathroom

 

[ian33a]

Even if you have to get in an electrician, in the long run, it's worth the effort of converting from halogen to LED. Kitchen lights, typically, are on far more than in any other room and the consumption really mounts up if you have lots of them. If you only have a few, it's definitely worth doing the work yourself, provided you are reasonably competent and confident to do it.

GU10 LED bulbs are relatively cheap these days. I would, however, bypass the really cheap ones. Look on Amazon and pick based upon customer rating, not purely on price. It may also be worth upgrading a few to a higher wattage in task intensive areas. In my office, for example, I have 10W LED's above my desks and 4 or 6 watts elsewhere. If you decide to do this, try to buy from a single manufacturer who can supply both with the same colour temperature.

 

[Ntre25]

I've got the same problem and I believe it's due to the transformers. Standard 12v transformers have a minimum Watt requirement which is higher than the 4 to 7 W LED bulbs. You'll need to get LED drivers and swap out the 12v transformers. By the time you work out what's involved, you might end up moving to gu10

 

[TomTheToolMan]

Go with Gu10 leds and rip out all the transformers. We had 18 off 50w gu10 halogen in our kitchen/dining room. Moved to led and saved about £30 a month (probably double that now). Personally I would just put in replaceable bulb fittings, especially if you have a lot in one ceiling, otherwise you will end up replacing everything when one breaks as the replacement has a different colour temp and looks different. I would echo the sentiment re cheap leds. The drivers can fail pretty quickly and you end up with them flickering. To be fair, the lap ones from screwfix have been pretty good. If you are going to do yourself the payback period is probably pretty short

 

[XTiffy]

One other benefit (in summer) is reduction in heat from the lamps. I had halogen in a kitchen and you could feel the heat as you passed under them!

 

[Deadeye]

Go with Gu10 leds and rip out all the transformers. We had 18 off 50w gu10 halogen in our kitchen/dining room. Moved to led and saved about £30 a month (probably double that now). Personally I would just put in replaceable bulb fittings, especially if you have a lot in one ceiling, otherwise you will end up replacing everything when one breaks as the replacement has a different colour temp and looks different. I would echo the sentiment re cheap leds. The drivers can fail pretty quickly and you end up with them flickering. To be fair, the lap ones from screwfix have been pretty good. If you are going to do yourself the payback period is probably pretty short

The other challenge is that I've got very limited access because it's all in the kitchen ceiling. So rewiring back to the switches isn't feasible.

 

[Agent_zed]

i had the same problem with some that I use in the garage. I just wired all 4 leds to one transformer so it saw the correct load. Been working fine for years now. As long as you meet the minimum load and don't go over the max load I can't see it being a problem.

 

[MorrisWoodman12]

Is there an ingress protection, IPxx, rating requirement for kitchen lights?

 

[Spectric]

Is there an ingress protection, IPxx, rating requirement for kitchen lights?

They should be fire rated, if for no other reason than your safety because plasterboard although not A1 rated will hold fire back long enough to evacuate the property but if you have loads of holes in it with downlights then this is no longer the case.

 

[Diver]

These days LED MR16's are 230 volt and do not require the transformer. Are your existing bulbs 12 volt ?


Not all LED's are dimmable and not all dimmers will drive LED's.

I had exactly the same problem with MR16's so changed all in the kitchen for GU10. Just turn off the power. pull out the wiring back to the 1.5mm (or 1mm) and it's connector, wire the new GU10 lamp holder to the connector and fit you dimmable GU10 LED's. Turn the power back on. Actually, mine are all over the house and like that when we moved in. I'll gradually changed them all as they go. I found LAP from Screwfix perfect. They've been in 18 months without a flicker.

 

[MikeJhn]

The other challenge is that I've got very limited access because it's all in the kitchen ceiling. So rewiring back to the switches isn't feasible.

You should not need to rewire back to the switch drops, that should already be in 1.5 T&E to a mains fed junction box, with red/brown sleeving on the blue/black where the transformers are fed from, you need to find this junction box to be able to disconnect all the transformers and run switched power too each GU10 downlighter.

 

[scholar]

I've been putting it off because I suspected it'd be a nightmare.

Same here

Most of the issues have been aired - the ones i have been musing over include:

- it is simpler to just replace with MR16 LED’s, but gets expensive with a new transformer for each unit;

- dimmer systems can be a bit tricky - we have Lutron dimmers and i think the choice of MR16‘s, in particular, that play well with those is a bit of a guess;

- you can fit a whole new GU10 unit, but is it the same size cutout? (our fittings have 90mm(?) cutouts so most new fittings would need some adapter plate;

- yes, if you have a habitable room over the kitchen, you need fire-rated fittings - a complication in one case for us where the fittings are not fire-rated and need replacing anyway (I am unsure whether they ever complied, but it doesn’t matter). And does the adapter plate carry a fire rating? (some do);

- you can look at converting MR16 fittings to GU10 (subject to the fire-rating point) with new bulb-holders, but that isn’t always simple - firstly, if the fitting is metal it needs an earth (unless otherwise properly certified by the manufacturer) and is it acceptable to add an earth? (there are differing opinions on this as far as I can see) - and secondly, some fittings have the bulb-holder integrated or riveted in some way that makes the adaptation more problematic.

- then you have the whole general issue with any LED’s in picking the right colour temperature, dimming performance, brightness etc etc, where the more you look into it, the more complicated it becomes!

It is not a small issue when you have 48 fittings in one room and about 30 in another - so I too have been putting this off and making do with trying to minimise the usage - so I am following the inputs here with interest.

Cheers