I'm just about to try the following.
We supply 4/5/6W 12V MR16 LEDs I noticed that they are made in component form, actually screwed together.
I've just taken the 5W one apart. The lens is an exact fit for lumicycle cans, the only bit of DIY would be making a heat sink as the original lamp it comes from uses the body as the heat sink.
Now I know it's not going to be as specific as 'properly' made set, but with the 5 and 6W chucking out the equivalent of a 50W halogen, it could be a useful quick and cheap way of putting some life back into those redundant lights.
You 5 watt led does not produce the same light as a 50 w halogen. More like a 10 w halogen. LEDs are twice as efficient as a hoalgen not 10 times
the beam spread will be too wide as well. Good for a commuting light to be seen by but not good for off-road riding
OK TJ
We use them as a genuine 50W halogen replacements in domestic applications is what I meant, and back then we were using 10 and 20W halogens in Lumicycles so therefore it would be similar to using 50W MR16s in Lumicycles (obviously they wouldn't fit)
For £15 and some very simple tinkering you'd have a bright set of lights.
However, Lumis were 13.2V not sure how it would effect these lamps, though they are designed to work with domestic 60Va transformers.
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Just out of interest, we did a lux test at 1 metre comparing them to 50W GU10s. The GU10 was about 750 lux the LED about 790.
The test waqs a 'shed type' test.
The other thing is that as it has the GX5.3 pins you wouldn't need to disturb the original lampholder and switch.
Any idea how the Lumi 13.2V battery would effect the 12V LED?
Got a link to the manufacturer's datasheet ? - and any pics of the internals ?
I'd guess they've got both a rectifier and smoothing inside (otherwise they'd spend a good portion of a cycle non-conducting). 12v ac (rms), smoothed/rectified is just under 17v, rectified/smoothed with no load, in which case there'll be some way of limiting/driving current to the leds (approx 11v in series) - tho' there will be a voltage drop under load. So I'd imagine a 12v ac/dc bulb would work with a 13.1V lumi pack.
From a quick browse, some appear only to be listing for use with ac - tho' I wouldn't have thought they'd really have some sort of transformer sitting inside.
Oh goody, more LED output BS.
we did a lux test at 1 metre comparing them to 50W GU10s. The GU10 was about 750 lux the LED about 790.
Completely meaningless unless the beam pattern of both is identical (given typical beam patterns, the LED will have significantly worse total lumen output given those figures). As TJ says, there's no way you'll get the same output as a 50W halogen from a 5W LED - certainly not a 50W halogen as used in a lumicycle, where overvolting leads to ~40% more light than a halogen bulb used in a domestic situation.
Given what I've seen of domestic LEDs I'd be very surprised if a single LED unit made for anything like a decent MTB light.
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This is just an idea for a simple led upgrade I'm going after USE or anything.
I fit lamps. Old Lumis used 10 and 20W halogens, these LEDs give the same 'sort' of light as an old 50W halogen. So if they light a room as well as a 50W halogen how can you say they'll only be as good as a 10W halogen?
For £9 if it works will give me a good road light or back up
Oldgit - they simply do not produce that much light - the manufacturers don't claim that much ( the LED manufacturers not the lamp unit manufacturers.)
Can you provide a link to the fact sheets for the leds please?
Are they Crees? Seoul? MCE / P7s? or what?
TJ I get to see them from the importer. We don't get a spec sheet just see them in use, and if they light up a house as well as a normal halogen we buy them. These are just the guts from a domestic High power LED.
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The lens fits bob on.
My mate workshop willdo a heat sink and I just need to solder up.
Look for a tenner I think it's worth a go.
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Have a go - it will make a good light to be seen by for commuting. and if you can sus out what actual LED they are then you can probably get different lenses to get a tighter beam
However I have been following LED tech developments the last few years and I assure you that they siply do not provide the level of light you say they do. Try comparing one side by side with a halogen.
Lumicycle sell a 1W CREE XRE LED lamp which I use for b/way and road, it is subjectively about as bright as their 5W halogen lamp, so I reckon oldgit's 5W LED would be more than handy.
The Lumi LED 'plugs straight in' and runs off my 14.8v Li-Ion battery with no problems
http://www.lumicycle.com/product/213/led1w_12mr11/1-watt-led-spot.html
Would this fit?
[url= http://www.ultraleds.co.uk/mr16-gx53-nichia-warm-white-lumen-2640-p-2033.html ]http://www.ultraleds.co.uk/mr16-gx53-nichia-warm-white-lumen-2640-p-2033.html[/url]
A five watt LED will be more than handy - it will be a decent light - around a 10 / 15 watt halogen equivalent. The main issue might be the beam pattern as it is likely to be too floody for offroad use. Its worth a try for sure and alternative optics may be available
It'll take my mate a few minutes to knock up a heat sink, I just need to borrow a decent iron.
Oldgit where do you source your 5W LED MR16's from for £9? Thanks.
I own an electrical wholesalers, my guy buys the latest from China 😐 those £9 would sell for about £18/20
You must realise though mine are for household use.
BTW - the pic's a little fuzzy, but it *does* look just like a smoothing capacitor and a bridge rectifier, as I'd suspected.
Oldgit,
Cheers. I need them for domestic use. More specifically in the bathroom and bedroom.
The LEDs are Edison, that's all I know.
No chance of a deal then?
I'll mailyou when my next lot come in.
Thank you.