DiY LED - Cree CXA3070

O my bad for some reason I read CXA, I forsee lots of model number confusion coming our way LOL. With the HLG B version you can dim down to almost zero, although it has been suggested that we should not go below 10%. If you want to use a separate knob for each driver, a pair of 100K pots, but if you want to dim both drivers with one knob, a 50K pot.

Awesome news that they are actually going to be able to deliver them!

SupraSPL said:

O my bad for some reason I read CXA, I forsee lots of model number confusion coming our way LOL. With the HLG B version you can dim down to almost zero, although it has been suggested that we should not go below 10%. If you want to use a separate knob for each driver, a pair of 100K pots, but if you want to dim both drivers with one knob, a 50K pot.

Awesome news that they are actually going to be able to deliver them!

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Linear power supplies can dim to zero, no problem. Switching PSU can be damaged with no load.

I can't imagine why I would ever want to dim to zero in a canna grow, but that is good to know.

SupraSPL said:

Each CXA3590 3K BD @ 500mA will dissipate about 35W @ 47% efficiency, so that is 350W of dissipation or 22W/ft² or 10.3PAR W/ft² in your 4X4. I think that would give you good results if you have short ladies, but I prefer and recommend greater intensity, 30-35W/ft² or 15 PAR W/ft².

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Thank you Supra. Is there any way to increase the intensity using those drivers? Like by running (3) or (4) cobs instead of (5) on them? Or is the .500mA going to be my limiting factor? Do you have a standard calculation you are using to get those figures? Thanks again for all your help.

Sure this is the data I am working with. The first column is the drive current. The 50C diss column is the dissipation wattage for each current assuming Tj 50C.



If you are looking to increase your intensity you could stay at 500mA and scale up the build, or you could go with a 700mA or 1050mA driver.

Thanks supra. Looks like I jumped the gun a little getting the .500mA drivers before I really had things planned out. I'm thinking now of running 6 COB's ((2)5000k and (1) 3000K) at the .500mA on the two drivers i have and running the other 8 at .700mA on two others. Then I can just run the .500mA drivers during veg and then flip the other 8 on during flowering.

alesh said:

I source them locally so no link. But they look like this. They come in a lot of different dimensions.
1"x1" shouldn't be more than $2-3/m.
View attachment 3364182

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How would you attach the cpu cooler to the L bracket?

lostenspacecadet said:

How would you attach the cpu cooler to the L bracket?

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I prefer screws. IIRC someone here even used some kind of magnetic attachment (inb4 ye, aluminum is a non-magnetic metal, you need to work around that). Very cool as you can move them in the bracket.

Recommended way to secure the Cree CX series to a CPU cooler? Would this LED holder work?
http://www.mouser.com/ProductDetail/TE-Connectivity/2-2154857-2/?qs=/ha2pyFadugAgPLTaG4bmekBcEb4TFyEA6KuG77EqLSR07yT7niOiA==

hey man straight up theres like only a few holders. That may work if you get right size. part number 50-2234C will work for sure though. I got them in the 35mm version. http://www.newark.com/ideal/50-2234c/led-holder-cxa30-array-series/dp/90W0065?CMP=AFC-OP ther is link. PS the cxb3070 are out and available for purchase. @bizfactory

Lighterfighter said:

PS the cxb3070 are out and available for purchase.

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I ordered 4 from digikey yesterday

cool so then I would say those holders I posted will work. I didnt see cxa listed on the product specs you posted.

https://www.youtube.com/channel/UCkuwpcjAkAGLLqNJi6MOEOw his top pic has L bar in it and shows use of cobs attached.

@bizfactory

Only the AB bin 3 step cxb is coming up on octo, 80cri, min output is the same as the cxa ABs but the max is 400 more.

And a 46 day factory lead time from digikey, no word at arrow. So theyre... "available." Dono how efficiency stacks up, but Im able to tell you I'm not moving till I see that 90cri cxb become available, that little loss in output is a huge gain in 630/660nms and blue.

That spectrum is so fuckin fine. THAT would be the emitter I would not bother adding reds/cool whites to.

Scotch089 said:

Only the AB bin 3 step cxb is coming up on octo, 80cri, min output is the same as the cxa ABs but the max is 400 more.

And a 46 day factory lead time from digikey, no word at arrow. So theyre... "available." Dono how efficiency stacks up, but Im able to tell you I'm not moving till I see that 90cri cxb become available, that little loss in output is a huge gain in 630/660nms and blue.

That spectrum is so fuckin fine. THAT would be the emitter I would not bother adding reds/cool whites to.

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The Vf of the CXB is lower than the CXA, so just comparing flux(at same mA) is not quite right. CXB are more efficient.

I was only looking at the datasheet I would hope the cxb is more efficient or what'd be the point? just pointing out the top bin isn't available and the next one down is hardly, if someone needed a light NOW I'd say go with the original cxa AB

I couldn't find the CXA AB in stock anywhere so I got the CXB AB. Plus I can run 4 instead of 3 because of the lower vF. My first grow is almost done and I want to have this thing ready for my next grow and the clones are already getting big!

Did they give you an eta? I think the cxa AB is only available in trays but several around here sell them out to other members.

Scotch089 said:

Did they give you an eta? I think the cxa AB is only available in trays but several around here sell them out to other members.

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Digikey said they would most likely arrive at their warehouse today 3/5 and would probably ship them to me tomorrow. ETA to my house would be Tuesday or Wednesday next week. I only ordered 4!

alesh said:

I prefer screws. IIRC someone here even used some kind of magnetic attachment (inb4 ye, aluminum is a non-magnetic metal, you need to work around that). Very cool as you can move them in the bracket.

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Thanks, do you have a photo. I'm trying to visualize this with the fins.
I've seen cutouts on plate but never an attachment to l bracket

not sure if I saw anyone ask,

CXA2 ? any better or worse or whats the deal? from what I understand is the dies are smaller .. ???