DiY LED - Cree CXA3070

those constant voltage drivers may be for strip lights which include series resistors on the strip to limit current when operated over a fixed voltage range. they are not safe to use an COBS of individual leds that do not have some form of current limiting device

sorry for being new...but i live in northern Canada and the closest place to by a soldering gun is 4 hours away....that being said supra or anyone.. have a website where we can buy all these parts? im very interested in building my own light set up..but i have a few questions.. does the heatsink need to be made for an LED chip or could I make a large CPU fan heatsink work cause i have lots of those..

CPU heatsinks are fine for single COB's. It's by far the cheapest way to go. Here's a link to a soldering iron for $10 usd. Other than that, most of the supplies drivers etc. can be found on ebay. For the LED's hit up mouser.com or digikey.com.

Supra,someone on another forum was asking about the Citizen COB's because of the availability and high prices of the CXA's and Vero's in the EU. Any thoughts on these?

http://www.tme.eu/en/details/cll032-1212a5273m1/power-leds-others/citizen/cll032-1212a5-273m1a2/

Thanks for the link Cap. I checked out the PDF and it is 1.4A max. So if we run it at 720mA as suggested we get 93.5lm/W in 2700K minimum. That is approx 29% efficient and it will dissipate 26W for $22 so $0.85/W. For comparison the CXA3070 Z2 at half power (1.4A) is 36.6% efficient and cost $0.77/W. So the CXA3070 is the cheaper and significantly more efficient

Thanks Supra,he linked two more,don't know if they are any better.

http://www.tme.eu/en/details/cll042-1218a5273m1/power-leds-others/citizen/cll042-1218a5-273m1a2/

http://www.tme.eu/en/details/cll042-1818a5273m1/power-leds-others/citizen/cll042-1818a5-273m1a2/

Good call Cap, the largest one is a more fair comparison for the CXA3070 but at half power it works out to be 28.6% efficient and cost $0.97/W

Looks like they compare to a mid bin CXA3050.

I just happen to have the mid bin 3000K CXA3050 in the spreadsheet already. At half power (1.25A) it is about 34.5% and cost $0.87/W.

I saw a table that Bueno posted of a CXA 3050 W2 2700k that looked close to those.

Oh good point, the CXA3050 2700K W2 is about 32.5% that is getting pretty close to the Citizen.

A solo cxa3070 doing work over some small plants. 29 days from seed, 3 days 12/12.

Bueno -
That's one 3070 lighting up all those plants?!?
Is it on a a motorized tracker of some sort that sweeps back and forth, or is the light fixed?
Are you shuffling these plants around so that each gets a turn under the COB?
Were all these plants recently moved under the 3070 from some other area? Or has it been this way from seed/clone?
Did you swap from a 5000K to a 3000K (or 2700K) when you flipped to 12/12?

It looks like the area is at least 2 ft. X 2ft. 12 plants. They all look healthy and relatively uniform. It's hard to imagine one CXA, even if it's being driven hard, taking care of everything.

Mellodrama said:

Bueno -
That's one 3070 lighting up all those plants?!?
Is it on a a motorized tracker of some sort that sweeps back and forth, or is the light fixed?
Are you shuffling these plants around so that each gets a turn under the COB?
Were all these plants recently moved under the 3070 from some other area? Or has it been this way from seed/clone?
Did you swap from a 5000K to a 3000K (or 2700K) when you flipped to 12/12?

It looks like the area is at least 2 ft. X 2ft. 12 plants. They all look healthy and relatively uniform. It's hard to imagine one CXA, even if it's being driven hard, taking care of everything.

Click to expand...

It is just one 3070 3000k z2 @ 1.4A since day 5 from seed, the light is just fixed in the center. I have been moving plants around a bit, right now the shortest two are in the center and taller ones on the sides. The lighting on the sides could be a lot better but they are doing ok under what they have for now. This is the veg tent they are in now I just flipped to 12/12 to give them an early start into flower while my flowering batch finishes up. My veg tent exhaust is really weak and I cant run both COBs in there, just the one COB until they get moved to the flower tent then I can add in the other COB.

I plan to make a led veg lighting setup eventually so I am using a more correct spectrum for veg and spreading light out better, two heat sink bars with 4 or 5 4300-4500k XM-L U2s on each bar and a 900mA driver but havent bought any parts yet.

Also forgot to mention veg tent is 1.5 deep x 2.5 wide x 2 ft tall and flower is 1.5 x 2.5 x 3. And there are 11 plants from seed starting flower in the veg tent, all are unsexed so far, going to need some males to show themselves so I can pull em out and make more room for the ladies. Last run out of 15 seeds I had 9 males and 6 females.

Its amazing what a minimal amount of light can do in veg huh.. nice work....

I just got a Kill A Watt, Im going to test the actual power draw on the 150w HPS tonight I think and test the COB with the MW lpc-60-1400 driver running it and also the power adapter running the heatsink fan. And probably a lot of random stuff around the house just for fun, get stoned and start measuring power draw on everything lol.

It is amazing the things you find that can save electricity. Also interesting to check the power factor to see which ones have been corrected. I noticed that my sump motor is not corrected by my vacuum is. Out of curiosity does your Kill A Watt measure tenths of Watts? Mine only measures whole numbers so I bought an Ensupra which does tenths, useful for small devices like fan PSUs.

SupraSPL said:

It is amazing the things you find that can save electricity. Also interesting to check the power factor to see which ones have been corrected. I noticed that my sump motor is not corrected by my vacuum is. Out of curiosity does your Kill A Watt measure tenths of Watts? Mine only measures whole numbers so I bought an Ensupra which does tenths, useful for small devices like fan PSUs.

Click to expand...

Yeah it is pretty neat I tested it on my end table lamp by the computer and on a box fan. Mine is the P4460 Kill A Watt EZ and it does measure in tenths of a watt which I didnt know it would but is nice.

I just tested and found out my ceiling fan on high takes less wattage than my box fan on low. Ceiling fan on high was 53.3w and box fan on low is 59.4w, ~100w on high, pretty crazy never would have guessed.

Being able to see the power factor is awesome too like you said. I bet the power factor is bad on the 150w HPS but Ill have to wait til lights on to test it, same with the COB module. I plan to test all the fans and lights separately and then also each tent as a whole to see the total wattage used on each.