49 XM-L U2 40 000lm watercooled bike lamp

siamese

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My latest project is a bikelamp using 7 of these (http://www.led-tech.de/de/High-Powe...2-auf-Kupfer-Rundplatine-LT-1847_120_117.html) XM-L copper boards and this (http://www.led-tech.de/de/High-Powe...en/CREE-7-Fach-Linse-12°-LT-1730_106_108.html) optic. The maximum power is about 570W, 350W is the maximum continous output with watercooling.

The power supply is a very simple boost-converter for a input voltage of 24-40 VDC (8s LiPo or 10s LiFePO4) and a output voltage of 190V maximum (limited, using 200V Fet and Diode) with 600W maximum output power. The Efficiency is greater than 95% in the range of 40W-300W and greater 90% in the range 10W-500W. The current output of the converter is controlled by a 0-5V signal fron a digital control. The control unit displays the battery voltage, the status of liquid cooler (pump on or off), the measures lamp power and the LED temperature calculated by the forward voltage and current. For this measurement it is necassary to calibrate the lamp at about 25°C lamp temperature from time to time (when you see that the tempereature display has a big difference to the real temperature) but it works very well. The water temperature at 350W is about 10-15 degrees lower than the LED-Temperature, this is a very good value and is due to the copper board.

Here a short video:



best regards

Thomas
 

Steve K

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that's just crazy! :)

I imagine that all of the rabbits and deer that you passed in the woods are rubbing their eyes and wondering "what the heck was that??!!".

Looks like a very fun project. Thanks for sharing!
 

MosesM

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I don't know about you...but I just burst out into laughter once you turned on the light on the trail. All I could think of was "Choo Choo I'm a freight train!!!"

Amazing work and thanks for sharing!
 

AnAppleSnail

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I'm extremely interested in a 1L heat-sink giving you several minutes of runtime below 50C at 300W.

(/me checks)

300W of electrical power, assume 250W heat 'worse case' (Not worst case, but not optimistic), 4.184 joules per calorie, one joule is one watt per second.

250W = 250 joules per second = 59.7 calories per second, so the liter of water would heat 0.06 degrees C per second, or 3.6 per minute. That checks out okay. I think most heat exchangers even with fans would heat up rather more.
 

siamese

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Well, a XM-L at about 2A has a efficiency of more than 30%. That means at 300W you have about 200W heat at your hatsink the rest is in your beam (well you cant hold your hand for a longer time closer than 1m to the lamp because the beam is really very hot).
And you have the 1 l Water but also about 1 kg alumium/copper of the lamp, and the convection of the big lamp and the bottle with the tubes (thats quite a lot at less than 10°C air temperature and >20 km/h speed). All this together gives you enogh cooling to ride at 350W until the battery is empty (1-2 hours). I did not test this but at more than 50 degrees (of couse only when you ride not in the lab) the temperture seems to be stationary.

best regards
Thomas
 

ncc74656m

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This is the fire of the gods! Wow. Just... wow.

I can't imagine how proud of yourself you are on this. You might consider looking into a copper radiator and fan like the PC modders use. Just a thought. :)
 

Steamdonkey

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Wow... And I thought my air cooled 12,600 lumen headlight was powerful. Mine provides an insane amout of light, I can't imagine more than 3 times what I've got now. I guess the pro's to my design are that I can use a smaller frame mounted battery and I don't have to deal with pumps and all the stuff needed for water cooling. Very cool though!
 

The_Driver

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If you check out his profile on youtube you will find more videos from his other projects..
This is only his most powerful led bike light. He has built a 1200W HID bike lamp with over 100.000 lumens, now thaaats powerful :devil:
 
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siamese

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I use the Cateye H-24 g for all my lamps. In my opinion this is the best solution for mounting DIY lamps.

br

Thomas
 

bstrickler

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IT'S USELESS WITHOUT STROBE!!! (Just kidding, but could you imagine that? You'll make everybody within 5 miles downrange have a seizure!)


I LOVE the end where you blast full power right as the car passes you, and they hit their brakes!


Maybe look into something like one of these to help cool the lights, rather than the water bottle:
http://www.xoxide.com/radiator.html


I don't know about you...but I just burst out into laughter once you turned on the light on the trail. All I could think of was "Choo Choo I'm a freight train!!!"

Amazing work and thanks for sharing!


I am so lucky I wasn't drinking when I read that!!
 

siamese

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Here another short video with a combination of the LED-lamp and a 400W HID lamp for spot. Really a very good combination!



best regards
Thomas
 

moozooh

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Ok, let me be "that guy" for a change...

I'll be honest. I think it is a very bad light for night riding, and in that sense it doesn't impress me at all. It's ridiculous, yes, but not something I would boast in front of actual cyclists.

It is way too excessive, if not outright dangerous for real-world use (and even more so the HID array from the other video). I consider it to be a product of mindless number race that ultimately makes no sense: by effect alone, what I've seen in the video feels more like 4000 lm. To be honest, even that seems excessive, because typical car headlights are only 2000 to 3000 lm each, and cars need those only because they run much faster. How is it that a slow moving bike might suddenly need 7+ times more light? Read on for our analysis!™

Construction
...Would fit a motorbike much better. As it is, the whole array is too heavy. A typical complete bike assembly with an aluminum frame weighs 10–13 kg, this lamp alone adds about 4 kg to that number. For the record, that's more than a pack of 15 Lupine Bettys glued together. Moreover, the assembly is too large and complicated. You need to pack your belongings (emergency kits, water flask, etc.) in a backpack instead of places now occupied with parts of the assembly, putting extra strain on yourself in addition to carrying forward those extra four kilograms. Your heavy panting at the end of the first video is very convincing! If covering some 350 m leaves you out of breath like that, you should look into reducing and optimizing your load instead of doing exactly the opposite.

Also, there are too many weak points scattered around the frame. With lamp in the front, makeshift cooler in the middle and power supply in the back you're just asking for trouble in night riding—a potentially dangerous enterprise that needs safety and robustness above all.

Usage safety
First of all, it runs too hot. It would expand the list of possible accident injuries far better than shrink it by the virtue of letting you see things better. And the injuries can't be ruled out because with an assembly so fragile and complicated, there are too many things that can go wrong with this light. Would it even be safe to use if a heavy rain catches you on the way home?

Another point to consider is that the beam is too wide for its purpose, yet too bright at the same time. You're bathed in glare from things you don't even need to see when you're on a bike. In the video, even dark grey trees roll over into white; any actual white or reflective (wet or shiny) surfaces could easily distract you or disrupt your vision, causing accidents. You can't use this light where you might meet other people even theoretically, either, because being hit in the face by 40000 lm at night would be pretty annoying, and might induce seizures in photosensitive people.

Illumination efficiency
This design might be power-efficient for the amount of power it draws, but the fact is that it needs too much power to achieve a much simpler purpose. It's essentially a low (close sight) beam overpowered to reach the intensity of a high (far sight) beam, completely ignoring all the good reasons for the distinction. It heaps more of the same 26° beam originating from the same spot for every distinct illumination task, not unlike using a single screwdriver for various screw heads.

The fact that the light uses some of the poorest contemporary high-power LEDs when it comes to color rendition doesn't help: XM-L U2 are only available in cool white, spec'd at ~65 CRI; whereas just lowering the CCT to about 4500 K would bump the color rendition up to ~75 CRI and give you more natural greens and browns. You have more than enough surplus lumens to spare for that purpose...

Bottom line: I understand that most of the decisions were dictated by cheapness and convenience, but a cleverly done combination of a softly diffused high-CRI low beam and a concentrated high beam could achieve exactly the same purpose in at most 40 W while having virtually none of the disadvantages outlined above, but of course some 3000-something lumen isn't exactly as mind-boggling as 40000—for both good and bad reasons.
 

127.0.0.1

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Ok, let me be "that guy" for a change...

I'll be honest. I think it is a very bad light for night riding, and in that sense it doesn't impress me at all. It's ridiculous, yes, but not something I would boast in front of actual cyclists.

It is way too excessive, if not outright dangerous for real-world use (and even more so the HID array from the other video). I consider it to be a product of mindless number race that ultimately makes no sense: by effect alone, what I've seen in the video feels more like 4000 lm. To be honest, even that seems excessive, because typical car headlights are only 2000 to 3000 lm each, and cars need those only because they run much faster. How is it that a slow moving bike might suddenly need 7+ times more light? Read on for our analysis!™

Construction
...Would fit a motorbike much better. As it is, the whole array is too heavy. A typical complete bike assembly with an aluminum frame weighs 10–13 kg, this lamp alone adds about 4 kg to that number. For the record, that's more than a pack of 15 Lupine Bettys glued together. Moreover, the assembly is too large and complicated. You need to pack your belongings (emergency kits, water flask, etc.) in a backpack instead of places now occupied with parts of the assembly, putting extra strain on yourself in addition to carrying forward those extra four kilograms. Your heavy panting at the end of the first video is very convincing! If covering some 350 m leaves you out of breath like that, you should look into reducing and optimizing your load instead of doing exactly the opposite.

Also, there are too many weak points scattered around the frame. With lamp in the front, makeshift cooler in the middle and power supply in the back you're just asking for trouble in night riding—a potentially dangerous enterprise that needs safety and robustness above all.

Usage safety
First of all, it runs too hot. It would expand the list of possible accident injuries far better than shrink it by the virtue of letting you see things better. And the injuries can't be ruled out because with an assembly so fragile and complicated, there are too many things that can go wrong with this light. Would it even be safe to use if a heavy rain catches you on the way home?

Another point to consider is that the beam is too wide for its purpose, yet too bright at the same time. You're bathed in glare from things you don't even need to see when you're on a bike. In the video, even dark grey trees roll over into white; any actual white or reflective (wet or shiny) surfaces could easily distract you or disrupt your vision, causing accidents. You can't use this light where you might meet other people even theoretically, either, because being hit in the face by 40000 lm at night would be pretty annoying, and might induce seizures in photosensitive people.

Illumination efficiency
This design might be power-efficient for the amount of power it draws, but the fact is that it needs too much power to achieve a much simpler purpose. It's essentially a low (close sight) beam overpowered to reach the intensity of a high (far sight) beam, completely ignoring all the good reasons for the distinction. It heaps more of the same 26° beam originating from the same spot for every distinct illumination task, not unlike using a single screwdriver for various screw heads.

The fact that the light uses some of the poorest contemporary high-power LEDs when it comes to color rendition doesn't help: XM-L U2 are only available in cool white, spec'd at ~65 CRI; whereas just lowering the CCT to about 4500 K would bump the color rendition up to ~75 CRI and give you more natural greens and browns. You have more than enough surplus lumens to spare for that purpose...

Bottom line: I understand that most of the decisions were dictated by cheapness and convenience, but a cleverly done combination of a softly diffused high-CRI low beam and a concentrated high beam could achieve exactly the same purpose in at most 40 W while having virtually none of the disadvantages outlined above, but of course some 3000-something lumen isn't exactly as mind-boggling as 40000—for both good and bad reasons.


incorrect. this light is awesome, and what the world sorely needed :laughing:.

good thing siamese is here filling these needs :devil:.

And this is coming from an avid bike racer (road/CX/mtb) :sssh:
 

siamese

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I don't want to comment all the comlete unqualified things postet by moozooh, but when you compare Lupine betty to my LED-Light the betty is really big and heavy!

Betty R9: 3,6 klm lamp 150 g (42 g/klm) set for 1,5h runtime 530g (147g/klm)
My lamp: 30 klm(360W) 1000g (34g/klm) set for 1,5h runtime 4000g (133g/klm)

At last 10 Bettys each 55mm diameter will take a little bit more room than my lamp with a diameter of 115mm...


And yes, you don't need lamps with up to 100+ klm like my big ones. But its great to ride with it. At last when I want to ride with only about 3 klm (exakt it is 2,5 klm), a small lamp and a high CRI here is my 2 years old answer:


A small HID with the philips CDMTC 35W (3000K CRI >90) weight of lamp 130g, ballast 180g, battery (3s LiIon, more when using 4s LiFe, for 1,5h 350g) output about 2500lm consumption 42W:

http://www.share-your-photo.com/img/57754f0019.jpg

http://www.share-your-photo.com/img/0124f665aa.jpg

http://www.share-your-photo.com/img/cc7751e9d4.jpg

At last it's everytime intersting to read comments about details and performance of equipment from people who never used things like that and don't have the expertise to judge about these things. Of course when you share such projects evertime some people will criticize with stupid comments because of the envy being unable to do this. Especially DIY-Projects provoke this because many people have enogh money to buy equipment but have no expertise in engineering, so when they can't buy it it can not be good because then can't get it. Everytime and in every country the same...


Your images are too large and have been replaced with links Please resize and repost.
See Rule #3 If you post an image in your post, please downsize the image to no larger than 800 x 800 pixels. - Thanks Norm
 
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wazza

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Sep 16, 2011
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REALLY AMAZING!

the only thing would how to get a very tight beam will all your XML cause a look for this combination
BUT need to focus ALL LEDs on a 5x8 cm ( and cutting all the IR cause must be cool light)


The video of Siamese looks a very wide beam that is perfect for cycling.
Obviously it need to be of road as the power of the light is somewhat dangerous.
 
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