My new 60W LED High beam!!.. Candela Monster!

These leds are betreen cool white and warm white.. they are similar to a normal 100W bulb... and an arc welder flash at the same time...

each led is wired in serie to a 1 ohm resistor then all 4 paralleled.

These 4 resistor act as a ballast shunt, protect leds against voltage Vforward difference from one led to another.. so they bright all same intensity.

They need 18.5V to operate (each led) and i operate them at 60% of the max current(700mA).

I wired a 78012 12V regulator that is perfect for the 12V 120mA fan. It only dissipate ((18-12)x0.12) Watts (0.72W).

so i need to put 18.5V at 1.8 to 2.0A.

I could drive them full power but i want to preserve their lifespan...

Doc
 
In the data sheet, I believe it stated the color temperature something like "4500-7000 Kelvin". Using a range to specify color temperature is not typical. Does the color temperature vary with voltage? I don't really see how the color temperature could be a range or how it could vary. I can live with 4500Kelvin but 7000Kelvin is too blue. Perhaps I'll just go the route I did with my camera light and use 12V standard MR16 replacement CREE LED lamps. They are a bit cool at 6000Kelvin but the quality of light is good. I've also found some "waterproof 5W Luxeon" outdoor 12v fixtures that might be nice as a bike light and have the advantage of running from a DC-DC converter instead of AA batteries like standard bike lights.

Doc, how are you getting the 18.5V for your lights? Did you modify a DC-DC converter? That type of modification is way past my capabilities so perhaps an off-the-shelf solution is more to my liking. One nice thing about the MR16 lamps is that they have a range of beam angles for sale. A 15 degree beam angle might make a nice headlight.
 
marvingalaxy said:
In the data sheet, I believe it stated the color temperature something like "4500-7000 Kelvin". Using a range to specify color temperature is not typical. Does the color temperature vary with voltage? I don't really see how the color temperature could be a range or how it could vary. I can live with 4500Kelvin but 7000Kelvin is too blue. Perhaps I'll just go the route I did with my camera light and use 12V standard MR16 replacement CREE LED lamps. They are a bit cool at 6000Kelvin but the quality of light is good. I've also found some "waterproof 5W Luxeon" outdoor 12v fixtures that might be nice as a bike light and have the advantage of running from a DC-DC converter instead of AA batteries like standard bike lights.

Doc, how are you getting the 18.5V for your lights? Did you modify a DC-DC converter? That type of modification is way past my capabilities so perhaps an off-the-shelf solution is more to my liking. One nice thing about the MR16 lamps is that they have a range of beam angles for sale. A 15 degree beam angle might make a nice headlight.
Click to expand...

to obtain 18.5V from 12V the best way is to buy on ebay a cheap DC-DC 12V to 5V.. then to adjust the output to 6.5V then to wire the output in serir with the input to obtain 18.5V.. dont forget the resistor to protect the led from overcurrent.

Doc
 
how about a vid of a nightride with these
you know real life use
becareful they look strong enough to stop
a deer like caught in your headlights...
and that would suck
 
wasp said:
how about a vid of a nightride with these
you know real life use
becareful they look strong enough to stop
a deer like caught in your headlights...
and that would suck
Click to expand...

Tonight it's full moon.. :lol: so i'll wait a bit to show you great relative results!
 
"to obtain 18.5V from 12V the best way is to buy on ebay a cheap DC-DC 12V to 5V.. then to adjust the output to 6.5V then to wire the output in serir with the input to obtain 18.5V.. dont forget the resistor to protect the led from overcurrent."

Could somebody translate this for me? I think Doc is speaking en Francais. Either that or I am horribly inept with electronic circuits. It's probably the latter. The way I read that is to hook the output back into the input a few times to try to make the device in series with itself. I'm pretty sure all I would accomplish if I tried to do these things myself would be to cause a short circuit and make blue smoke.

Do pre-packaged LED lamps have the aforementioned resistor already in place? Since you bought the LEDs as components do you need to add the protection yourself? I just hook up my LED MR16 lamps to a 12V battery and they work just fine. Of course, they are nowhere near as powerful as 60W LEDs so they won't make such amazing headlights.
 
Here is the first clip of the intensity measurement on the lab at my work.

All equipment are calibrated at least every years.

I'll post next clip soon

enjoy

[youtube]6mjn5duO5Tw[/youtube]
 
Those things are certainly bright. Your room looks like it is being lit by a projector (~200W HID lamps). It is hard to tell by the video alone, but I'm guessing that you can't get the LEDs to the focal point of the parabolic reflector. It seems that they are throwing a lot of the light out to the side instead of what would be 50 meters down the road in a tight beam. Does it seem like a tight beam in person?
 
Doc,
Avec 15W pour 420 Lumens le rendement lumineux est fort médiocre... (pour des leds) (28 lm/W)
Pour mon phare j'utilise des led mesuré à plus de 80 lumens par W :mrgreen:
Ainsi avec 4W consommé j'éclaire autant qu'une lampe halogène de 35W (et le phare ne chauffe pas... le refroidissement naturel suffit largement)
Ça éclaire suffisamment mais si je voulais produire autant de lumens que toi, il me suffirait de mettre 5 fois plus de led (ce qui reste très faisable) et je ne consommerais que 20W...
Bon, c'est vrai que des leds 5mm ça ne fait pas aussi fun :D
Silicium
 
marvingalaxy said:
Those things are certainly bright. Your room looks like it is being lit by a projector (~200W HID lamps). It is hard to tell by the video alone, but I'm guessing that you can't get the LEDs to the focal point of the parabolic reflector. It seems that they are throwing a lot of the light out to the side instead of what would be 50 meters down the road in a tight beam. Does it seem like a tight beam in person?
Click to expand...

These reflector ARE coming from 1W stars led.. so they fit perfect with my actoal 15V led.. they also have a lens on the led. Both combined allo all light to be directed in front with minimal side loss.

I would say that 80% of the light is in a very narrow beam of like 5-7 degree and the rest islike 40degree. the color temp is a bit low close to thungsten.. so the eyes are more sensitive than if it would be blue white...

I agree that these led are not the most efficient.. but their power density is one of the highest.. so i can put focal of the reflector easier than with a large group of dozens of led.. so i can better control the beam.

Doc
 
That is good to hear. It is hard to tell exact brightness from a picture. I'm guessing that your 40 degree side spill is so bright that it looks like the main beam in the video. It's also nice to know that they don't look blue to your eyes. I can see the color difference between your desk lamp and the LEDs but what is important is how it looks to your eyes. If it doesn't seem blue to you then they are probably 5500Kelvin or lower which is a very useful range. When lamps get above 6000Kelvin they don't look natural.

At 28 lumens per watt they aren't as efficient as less powerful LEDs but they are still about twice as efficient as halogen/tungsten. Thanks for being on the cutting edge so we know what is possible.
 
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