DiY LED - Cree CXA3070

Thank you Supra, you are a huge help, the plan is to run CXA3070 3000k for the flower side and CXA3070 5000k for the veg side at first and see how they work then add a few additional heatsinks of ? when the wallet fills back up. Using either of those drivers it leaves me around 30 watts to add unless I put them on a new string but I like the idea of keeping things simple with only 3 total drivers. I took a shot at buying those AB cobs off of a seller on AliExpress, $38 bucks each shipped to my door but who knows what I will get. Might be an expensive lesson learned rather than a deal, time will tell, still waiting on them to ship.
 
I have been looking for a driver to run 2 - Z4 cobs, maybe dimmable up to 1400 ma? There's probably a link here some where but I can't find it. Checked out ebay, but no luck. I am a little confused maybe.
 
SupraSPL said:
Then third possibility is true widespread bleaching from overly intense light in the entire upper canopy, even without the plant growing into the lights. Do you have pics of yours Happy?
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I can definitely attest to the bleaching in this example, as both of my plants are showing this.
 
SupraSPL said:
Hey KK sorry to hear about the COB but the Alpine 11 will take care of you. Regarding the thermal shutdown protection, maybe something along these lines on the AC power wire?
http://ac-rc.net/catalog/product_info.php?cPath=27&products_id=70&osCsid=hn85urr92h14oncttqurrcvp56
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You have saved the day. I was looking at the driver and it seemed to reduce the voltage if the temp got high, but does not shut down. Your link is exactly what I was looking for. Could I use two or more of them to control the temp of multiple cobs and if so how would I wire it?
 
As you may know I was planning a small flower room of 60cm x 60cm running 4 x cxa3070@700ma. I got an offer for some cxa3590 36V chips, which fell threw and I ended up with one cxa3070 3000K and one cxa3590 2700K. So I have been redesigning my setup and redoing the costs for the cobs, drivers, etc. Then I had a good idea which will half the cost of my setup. Although this may not work for large setups it is ideal for my needs.

The first thing I did was build a reflector. I have a round lamp shade, which I covered with reflecting sheets so I have a 12cm diamiter cone with a height of 5cm providing a 90 degree reflector.

The second thing I did was split my flower room in two using my reflecting sheet. The top part is 10cm wide and covered with foam plastic covered withe oil. I added two wooden rails and housed the two lights in two shoe boxes attached together. Using two timers, two 12V 1A drivers and one hand hend screwdriver, I have setup a moving light with on 10W 730ma light in the middle. For 11:45 the light stay in the first part, the lights out, 15 mins of 730ma, then the light moves to the other half of the room, where the cycle is repeated.

So I run my flower room lights 23:30 a day to cover the same area as 4 lights, with 2 lights + £30 to setup the lightmover. The lights weight is less than 1.5 kilo's and I think the screwdriver will be able to move as many as 8 lights, which could cover 120cm x 120cm.

Lastly I removed the aritic alpin 11 fans and replaced them with 120cm fans. The overlap around the heatsink means the fans provide enough airflow so I no longer use any other fan as the cobs are hung aroung 15cm above the canopy and the extraction fan clears the air every 5 mins.
 
medicinehuman said:
I have been looking for a driver to run 2 - Z4 cobs, maybe dimmable up to 1400 ma? There's probably a link here some where but I can't find it. Checked out ebay, but no luck. I am a little confused maybe.
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I would recommend browsing mean well units on TRC electronics. You can price shop after finding what fits your needs. Jameco is usually the cheapest after shipping costs.
 
epicfail said:
@kkman

You don't get light leaks? How are you controlling the timing of the on/off and movement cycles?

Shoeboxes sound flammable.
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Hi

I did'nt want to write to much about this unless there was some interest so I did not do a good job describing the steps.

The top of the flower room has a cut in it 40cm x 40cm. The shoe box is actually made from .5cm plywood I cut in the shape of the shoe box. It is 20cm x 40cm. On each 40cm side there is 5 cm rubber which is 2cm thick.

The middle of the grow room has the reflector sheet which goes up to the rails which the shoebox sits on. The top of which is 10cm wide covered again with 2cm thick rubber. The trick was to have the rubber 1 cm higher in the middle. So when the box is moved to the let, the right side hits the center rubber goes up then down and in its rest position is slightly pushed down by the weight of the box. Also using the greese makes the box rubber stick to the wall rubber as well as help the hole thing slide easier.

It took me a good day just to cut the rubber straight so the hole thing was in full contact and stop the light leaks. That isthe hardest part.

As to the wiring. I removed the screw driver from its casing. Connected one driver to its + and - and the other driver the other way around. The timers have a 15 min interval. So for 15 mins, the screwdriver rotates one way. This moves the shoebox untill it hits the outer wall. The string I use is plastic and after the box hits the wall the screwdriver shaft simply rotates until the power cuts off ( 15 mins ).

If this is of interest I can provide more info.
 
supra i am planning on building a new light and still am not sure on how to figure how much heat sink for passive cooling i need.each heat sink will need to passively cool 4 cxa 3070s run at 50 or 60 watts each with the chinese drivers.three foot long will work perfect for my light spread.i plan on using heat sink usa and what ever one you recommend for this set up.

i run 4 foot by 4 foot by 6 foot high cabinet with 1 plant on each wall tied up .currently i use 2 600 watt hps stacked bare bulb vertically.i plan on building 4 3 foot heat sinks and mounting them in a 3 foot long aluminium 6 to 8 inch square box.there will be a fan pulling on one end and another pushing on the opposite end.my other option will be to add a 6 inch vortex fan to one end and route that directly out of the cabinet like a cool tube.i will cutout where the cobs will be so heat sinks will be mounted flush to the inside of the aluminium box.i do not think 16 will generate more heat then 2 600 hps bulbs and i have a 8 inch fan filter combo pulling air out from the top center of the cab and except in summer i can usually run them at 100%.i am trying to lower my electric bill and maintain better temp control without more ac.
thank you for all the info you provide everyone and any help you can give me!
 
Hey ZEP, that would be an awesome project and would give us very useful data to compare your results to the vertical HPS.

It sounds like your setup will have lots of air moving along the heatsink fins so it will perform like an active cooled heatsink. So if you allocate 40cm²/W, for 832W you would need (4) heatsinks of 5.88"X32", a perfect match :leaf:
 
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SupraSPL said:
Hey ZEP, that would be an awesome project and would give us very useful data to compare your results to the vertical HPS.

It sounds like your setup will have lots of air moving along the heatsink fins so it will perform like an active cooled heatsink. So if you allocate 40cm²/W, for 832W you would need (4) heatsinks of 5.88"X32", a perfect match :leaf:
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i know it will be a active cooled sink ,i am of the mindset that i would rather pay extra on the sink to have overkill and if the fan breaks i dont fry 16 cxa's!i liked that heat sink but was not sure if it would be safe if the fan failed.i am away from the grow for days at a time.
 
since this is a test run,i am debating building it with chinese cobs.i can do the whole test for less then what 20 z bin cxa's cost from arrow.if i like the temps and the light spread i can order and change out the cobs.
 
Glad to help :leaf: There is no guarantee with those drivers but as far as the specs and the picture, that is the correct driver. If so, it should have power factor correction and good efficiency >90%. It should have enough Vf range for almost every CXA3070.
 
Zep, amazingly the CXAs may actually be cheaper /PAR W when you work out the math. The Chinese COBs will create a TON more heat than the CXA and maybe only half the light. I daresay they would create as much or more heat than the 1200W of HPS. But if you build the system with CXA ABs and decide you don't like it, I expect you would have no problem selling the lamp, probably at a profit.
 
@SupraSPL

Is there a driver that can handle at least 2x of the AB's voltage-wise in a series, but also has current output up to 2.1 amps or so?

Bigger version of the Meanwell HLP 80-42? Maybe :joint:
 
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