New 10x Cree project

[Grim Reape®!!!]

I've just started on a new project, including 10 Cree XR-E Q5, mounted on a 12mm piece of aluminium.

I'm using 2 1400mA constant current supplies, each driving 5 LEDs, and a TTL dimmer so i can adjust the light.
I'm planning om using 2 14,4V/1600mAh LiIon batteries in series, would that bee too much for the drivers, and should i stick with 2 11,1V 1,360mAh LiIon batteries?

Another question, how many lumens can i expect from a Q5 driven at 1400mA?

Side and front view of the "gun"

 

[saabluster]

Another question, how many lumens can i expect from a Q5 driven at 1400mA?

Here you go.

 

[TONY M]

Waow, looks good. Is it for a bikelight?

Good luck with the project!

 

[glockboy]

Now, still using it.

http://www.candlepowerforums.com/vb/showthread.php?t=158356

 

[R33E8]

I've just started on a new project, including 10 Cree XR-E Q5, mounted on a 12mm piece of aluminium.

Are you using the 12mm piece of aluminum as the heat sink?

Well I hope your not. If you are you might want to add a large heat sink to the back of it. 12mm will definitely not be enough metal dissipate all of the heat.

 

[saabluster]

Are you using the 12mm piece of aluminum as the heat sink?

Well I hope your not. If you are you might want to add a large heat sink to the back of it. 12mm will definitely not be enough metal dissipate all of the heat.

He has not given us enough information yet as far as what he intends to use this for, ambient temps, what it will be attached to, etc. If he is thinking of just having this plate all by itself running at that level than he is in for a surprise. He will need a heatsink as you say. Also, just a minor point, its not so much that he doesn't have enough metal(12mm is pretty chunky) its that there is not enough surface area.

 

[saabluster]

Now, still using it.

http://www.candlepowerforums.com/vb/showthread.php?t=158356

And still one of my all-time favs.

 

[Grim Reape®!!!]

Now, still using it.

http://www.candlepowerforums.com/vb/showthread.php?t=158356

Nice light you've got there, maybe i can use some of your ideas on my project.

Are you using the 12mm piece of aluminum as the heat sink?

No i'm just using it as a heat spreader, i'm planning to use a huge CPU-cooler with a temperature controlled fan.

As for the use?... just a standard photon accelerator for showing off :tinfoil:

 

[Stillphoto]

Does the dimmer you're planning on using employ PWM?

 

[Grim Reape®!!!]

Does the dimmer you're planning on using employ PWM?

Yes, it's THIS one.

I've changed the blueprint to a more current one

 

[Grim Reape®!!!]

I've designed the "gun" and the drawings has been sent to lasercutting in 2mm stainless steel.
The heatspreader will propably be made of 10mm copper insted of 12mm aluminium.

 

[saabluster]

I've designed the "gun" and the drawings has been sent to lasercutting in 2mm stainless steel.
The heatspreader will propably be made of 10mm copper insted of 12mm aluminium.

That is going to be one really heavy light. Definitely not something you could aim at something for any length of time with one hand. Nice Star Trekky feel to it though.

 

[MorePower]

I'm using 2 1400mA constant current supplies, each driving 5 LEDs, and a TTL dimmer so i can adjust the light.
I'm planning om using 2 14,4V/1600mAh LiIon batteries in series, would that bee too much for the drivers, and should i stick with 2 11,1V 1,360mAh LiIon batteries?

The specs for the driver you linked says that 3V over Vf of the LEDs is max supported input. Vf for a string of 5 at 1400mA will be around 18 volts. Using 2 14.4V batteries in series would be running the drivers well out of spec. Using 2 11.1V batteries in series would be better, but still out of spec, since the 11.1V batteries will come off the charger at around 12.6V each.

 

[Grim Reape®!!!]

The specs for the driver you linked says that 3V over Vf of the LEDs is max supported input. Vf for a string of 5 at 1400mA will be around 18 volts. Using 2 14.4V batteries in series would be running the drivers well out of spec. Using 2 11.1V batteries in series would be better, but still out of spec, since the 11.1V batteries will come off the charger at around 12.6V each.

Thanks, you've propably saved me from destroying the Drivers.
I've been using the specs from led-tech.de, wich claims a Vf of 4V, wich i can see is ridiculous high.

 

[snarfer]

If you used one CCHIPO boost driver instead, and put the batteries in parallel, you might get better run time due to higher efficiency. Also you would be able to dim with a single potentiometer. Just my .02 USD

 

[Grim Reape®!!!]

If you used one CCHIPO boost driver instead, and put the batteries in parallel, you might get better run time due to higher efficiency. Also you would be able to dim with a single potentiometer. Just my .02 USD

The CCHIPO can only deliver 45W, and i want to drive the CREE's at 1400mA wich needs 51W.
I also already have the 1400Ah drivers, so i think i'll stick with them.

Regarding the batterypack, i'll make a couple myself.
Got a nice deal on some CGR18650's (2200mAh, 3,7V)
Should be no problem for the drivers if i cool them adequately.

 

[Oznog]

Resistor PWM is a terribly cheap, poor driver for this kind of thing. It's inefficient, lots of heat, limited capacity, poor regulation with changes in batt voltage and forward voltage, and it surges current into the LED which is kinda bad for the LED's life when you're trying for peak power.

You want something using a current-mode buck (or boost) converter. Recognizable by an inductor on the board. Now these converters DO use PWM but it's a completely different application that PWM+ballast resistor. These are always in the high 90's for efficiency, making a teeny driver for 10A+ is easy too. 15% ripple, or less, is easy to achieve. But the really important thing is they're current-regulated and won't change the LED current even with wide swings in Vdd or the minor swings in Vbatt. Look up HV9910. There are other chips but I don't have 'em listed right now. The main limitation of the HV9910 is the minimum Vdd voltage required though.

 

[Grim Reape®!!!]

Resistor PWM is a terribly cheap, poor driver for this kind of thing. It's inefficient, lots of heat, limited capacity, poor regulation with changes in batt voltage and forward voltage, and it surges current into the LED which is kinda bad for the LED's life when you're trying for peak power.

I've been using the same PVM dimmer in several other projects, and it have never gotten hot at all. One of the projects draws 8A at 24V, so i don't think that will be a problem.

 

[Stillphoto]

Hmm, this electronics setup looks like exactly what I need for a project of my own. Mine would involve the nichia 083 leds found in Don's Sundrop light.

I can solder, now I just wish I had a clue about the voltage side of everything.

I'll definitely keep my eye on this thread.