Help me create a 50W LED system

[tsk1979]

I found this on aliexpress
Aliexpress.com : Buy 30W Constant Current LED Driver DC12V to DC30 38V 1000mA for 30W High Power LED from Reliable driver suppliers on LED World company

and I also found this driver from same seller
Aliexpress.com : Buy 30W Constant Current LED Driver DC12V to DC30 38V 1000mA for 30W High Power LED from Reliable driver suppliers on LED World company

I guess, I just need a heatsink? What do you suggest. Something from an old processor and some thermal glue?

Tips please?

 

[tsk1979]

Ignore the page heading. Its actually 50W

 

[DashApple]

Large heatsink with thermal grease , but a very thin layer then hold the led down with screws .

My 90W led at 31V @ 3.1 Amps chucks abit of heat out , so use good fans , I used a large heatsink , but you could get away with a large cpu heatsink

 

[BShanahan14rulz]

Don't buy a driver without knowing what LED you are going to use.

 

[tsk1979]

Large heatsink with thermal grease , but a very thin layer then hold the led down with screws .

My 90W led at 31V @ 3.1 Amps chucks abit of heat out , so use good fans , I used a large heatsink , but you could get away with a large cpu heatsink

Don't buy a driver without knowing what LED you are going to use.

Thanks for your tips. I will buy the driver and the LEd together from the same seller.
Can you offer more tips on your system @ionlaser555

I have never made a flashlight before.
So I guess I need
1. Lens assembly with LEd chip - Sorted out, the link has everything
2. Driver - From link
3. Heat sink - Old CPU
4. Tube to take in 3 16340 cells (3.7*3) since I will use a 12V driver?
5.. A clicky switch.

Tube I will have to get done on a lathe somewhere?

 

[BShanahan14rulz]

I didn't look through the links thoroughly, I just assumed you linked to two drivers without telling us what LED you used. That's fairly neg rep worthy, IMO, sorry about that!

50W LED Chips:
Output Lumens: 5000-5500 Lumens
Forward Voltage (VF) : 30-36 Vdc
Forward Current (IF) : 1500 mA

Assuming worst case of 36V when driven at 1.5A:
P=I*V
P=1.5*36
P=54W - that's ~54W coming out of the driver.

Assuming 90% efficiency, the driver requires 60W input. Input is at 12V.
P=I*V
60=I*12
I=5A. - 5A is a bit much to be pulling from a 16340. the 2C rule of thumb says you should keep 16340 amps below ~1.5A. This will be a bottleneck you need to resolve. You may need to consider a different host that can accept 3x18650 in series, or even 4 in series if you think the driver can handle a maximum 16.8V. Google "sky ray king" or "DRY" for some host ideas. Might even fit that LED without looking half bad!

clicky switches are hard to find in high amp variants, but perhaps a nice beefy rocker switch will give it a good utilitarian look and feel, and can be easier to find high current switches.

 

[tsk1979]

Thanks!!
I have a fandy fire which takes 4 18650s and looks the same as the Sky ray king! It cost around 50 USD.

I think first I will assemble driver+led+heatsink, and try a drive from a 12V sealed lead acid UPS battery.

 

[weirdmeister]

take 4c lipo (14,8v)
ask the seller for max input of the converters

i build a 50w desk lamp and for example a cnps-5x cpu cooler need very low fan rpm´s to cool this so a smaller cooler can do the job also