Replacing 50W Halogen GU 5.3 / MR16 with LEDs... unanticipated problem

Forums › Home Workshop DIY › Replacing 50W Halogen GU 5.3 / MR16 with LEDs... unanticipated problem

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#1273510 30-Mar-2015 16:13

12w do exist, they are really really deep.

The philips I tried had a very sharp cutoff at the edge of its beam, but they brand so many products its hard to know if it was the same as your one.

Richard rich.ms

Niel

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#1273656 30-Mar-2015 19:06

Most high power LEDs from "Chinese" web sites spec the LED maximum power, not the power it is running at. In Europe it is law that you need to state the "lumen" light output, which is much more useful than wattage (when it comes to LEDs).

As a reference, a Click 5W GU10 bulbs (also available in MR16) from Bunnings have a wide angle enough to light our large bathroom with 1 bulb to the equivalent of about a 40W incandescent. This is in a Heat & Vent fitting. It is not enough for my wife to do her make-up, but enough to see what you are doing and will not wake my wife up when I use it in the middle of the night (nor wake me up when I use the bathroom). The original halogen however was useless as it made a spot on the floor and the rest was dark. Recommended if you want to light up the whole place instead of having spots.

You can never have enough Volvos!

heylinb4nz

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#1273968 31-Mar-2015 09:39

aros71:
heylinb4nz: Ideally you need to be using 12W MR16 LEDs if you want to get anywhere close to 50W halogen equivalent lighting.

I've found the Philips 5.5W ones subjectively to be equivalent to 50W halogens.

The box lot of 3.5W ones I got from AliExpress are approximately equivalent to a 20W halogen.

I have never seen a 12W MR16 LED... do they even exist?

In the end, I just started replacing transformers through the house, it's just a slow process as pretty much all the lighting in my whole house (4bed 3bath 2storey) is MR16 12V halogen. Wondering what the hell they were thinking. There's about 70 lights at a rough count, including effect lighting outside.

Vaguely ridiculous

Yep they do exist, but as poster above stated they are rather tall (approx 3-4cm taller). For mine I had to chop the tops of my old halogen housings to accomodate...but apparently thats what you need to do, LED heat sinks need airflow, many of the cans in your roof space were designed for Halogens (ie keep heat away).

From my Chinese bulb testing I was getting around 45 deg C on the heatsink after 2 hours of running, also confirmed the plastic base was non flammable. Safety wise I am comfortable they pose no fire risk (im also running Bradford Gold insulation which is triple zero rated ie pretty much fire proof)

jackperez

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#1288909 22-Apr-2015 07:46

aros71, good to know that you’ve already accounted for the power output of transformers. Also, putting fuses in the lines of these connections is an excellent idea, if you can add a very small resistor in the lines for current limiting, that’ll be a very safe bet as well. You won’t be able to get a light as bright as the one being emitted by the halogen lights but you’re going to save a serious amount of money on your power bill.

Niel

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#1289858 22-Apr-2015 23:40

aros71:
RunningMan: Can't answer your specific question, but as a side issue, be careful that you don't add too many LEDs per transformer, as you need to account for someone else coming along and replacing the LEDs with the original halogens, and then overloading...

Also I'd put a 5A fuse in the 12V line upstream of the distribution to stop total draw > 60W off the transformer. Trouble is, I've several rooms to do this in, so I want to work out the best plan to avoid expensive trials and errors.

It is of no use. A fast blow fuse (you also get slow blow or time delayed fuses) of 5A rating will easily last 1h at 7.5A, 30 minutes at 11A. It is only when you get to around 14A that is will fuse within a couple seconds. Fuses are for low impedance short circuit protection, it is not a controlled trip device. If you use an electronic transformer, then it already has current foldback built-in. If you use a traditional AC transformer, then you (or the next person) run the risk of blowing cheap unregulated bulbs (i.e. unbranded eBay etc. bulbs).

You can never have enough Volvos!

richms

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#1289859 22-Apr-2015 23:47

All the cheap eBay lamps I have are using a constant current driver so are fine from 11v to at least 18v.

Problem I find is they are still assuming AC input so have a diode bridge on the input. There goes 10% of your power when on DC needlessly.

Richard rich.ms

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#1289892 23-Apr-2015 07:09

I have a number of eBay and DX 12V and mains bulbs that use a rectifier and capacitor, no CC driver. One of the issues being discussed is "the next person" replacing bulbs without knowing what is suitable and what is not.

You can never have enough Volvos!

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jaskarn

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#1293058 28-Apr-2015 16:29

I'm also trying to replace 50w MR16 Halogens with LEDs
My question is would they work with this transformer? I noticed it says 20-60W on it- does that mean it won't turn on a 7w LED bulb?

We've got 144 halogens so the power savings should be substantial. Has anyone found good quality, reasonably priced MR16s in the market yet?

aros71

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#1293062 28-Apr-2015 16:43

jaskarn:
My question is would they work with this transformer? I noticed it says 20-60W on it- does that mean it won't turn on a 7w LED bulb?

Most likely not, in my experience. They might turn on but they'll flicker quite strongly.

jaskarn:
We've got 144 halogens so the power savings should be substantial. Has anyone found good quality, reasonably priced MR16s in the market yet?

I bought some of the Philips ones from Bunnings, $50-odd for a pack of 4 - 5.5w - they were good. Then I bought an 8-pack of the cheaper ones from Bunnings for the same price, they were also good. I then bought 20 from AliExpress which were tolerable but nowhere near as good as the Bunnings ones. (in terms of light output and spread)

hangon

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#1293468 29-Apr-2015 12:24

aros71:
jaskarn:
My question is would they work with this transformer? I noticed it says 20-60W on it- does that mean it won't turn on a 7w LED bulb?

Most likely not, in my experience. They might turn on but they'll flicker quite strongly.

jaskarn:
We've got 144 halogens so the power savings should be substantial. Has anyone found good quality, reasonably priced MR16s in the market yet?

I bought some of the Philips ones from Bunnings, $50-odd for a pack of 4 - 5.5w - they were good. Then I bought an 8-pack of the cheaper ones from Bunnings for the same price, they were also good. I then bought 20 from AliExpress which were tolerable but nowhere near as good as the Bunnings ones. (in terms of light output and spread)

the philips from bunnings are good - they have vents though

the sylvia from mitre10 are also good - no vents, similarly priced, $16 a pop from back of my head, no multi packs.

jefflouttit

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#1595286 19-Jul-2016 20:20

Hi all. Has anyone had any luck with finding compatible LEDs in 2016? Specifically I'm looking for 12V MR16s that will work with 60VA electronic transformers.

Thanks for your expertise!

richms

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#1595291 19-Jul-2016 20:24

Hit and miss depending on what the power supply you are running them off will support. If it is a common one like the possum or from a large chain then they will have ones they can recommend, but if its random stuff from a big box hardware retailer then good luck with that.

Even worse if you expect dimming.

IMO just replace the fitting if they are plain MR16 ones with nothing special.

Richard rich.ms

jaskarn

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#1595591 20-Jul-2016 12:45

I bought these last year and they've been working fine for me:

http://reductionrevolution.com.au/products/philips-master-led-mr16-5-5w-3000k-60

jefflouttit

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#1595636 20-Jul-2016 13:59

By total chance today, I ran in to an acquaintance who is a lighting designer. He said there is technology by Philips that negates the worry for transformer compatibility. Perhaps that's the same bulb Jaskarn. However he said his company is getting similar (but crucially cheaper) bulbs over of a different brand in the next week that also have this technology. I'll keep you posted to see if it works. It seems absurd that such a common light fixture doesn't have an economical solution for upgrading to LED!

CrashAndBurn

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#2318977 17-Sep-2019 10:08

I just bought some of the Philips MR16 and found out they are not compatible e.g. it flickers the minute you turn it on. Unfortunately I live in an apartment and could not check as to what transformer it currently have. Any recommendation on brand replacement for the 50w 12v halogens.

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