DiY LED - Cree CXA3070

[SupraSPL]

Been awhile since I've checked this thread. Nice to see its still going strong a year later.

I stumbled across some interesting drivers that might work well for fans. Thought I'd share:
http://www.ebay.com/itm/261653490178?_trksid=p2060778.m2749.l2649&ssPageName=STRK:MEBIDX:IT

At $1.59 each seems kind of hard to beat and gets away from using multiple wall sockets.

Thanks for the encouragement I have seen those adapters linked but have not tested them for output and efficiency yet, I will give it a shot thanks.

 

[nestor]

I ordered 10 of them a couple of weeks ago so they should be here any month now. Other than a multi-meter and a kill-a-watt meter I have laying around is there any other equipment necessary for that? Or to ask another way, how do you test yours?

 

[SupraSPL]

When you say 30070 ab > 3590 bb is that only for the 36V 3590 or the 77V version as well. Also is that based on the cost of the units or the actual light they produce.

I agree with Alesh, the CXA3590 36V and 72V are equally matched on paper. The main difference is how it affects your choice of drivers. Generally speaking, it is cheaper to make a high voltage driver than a high current driver. For example we can get 280mA, 150V drivers for $7. That driver run a pair of 72V CXA3590s at 18W each, an expensive but viable current to run them at.

I mentioned the BB because it was "in stock" for a fair price. Sometimes resellers give the impression that they can provide a specific bin but when you go to order it they realize they cannot source it either and they cancel the order. Otherwise we could order the CXA3590 36V 3000K CB bin, which beats even the CXA3070 AB in terms of efficiency, cost and output. BUT if you do have a reseller than can actually source the BD bin, it would just about match the CXA3070 AB in terms of efficiency, cost and output, a very good choice.

Lastly if 200ma is too low, what would be a safe min to go for. This is the hardest thing for me to get my head around. what size array 4x4,5x5,etc. can I use to get to 15-20W per sqft and still have a light which works as well or better than my current 4x4 array running 700ma-900ma using 3070 z2 cobs. So currently running 25W-35W, so in total I would use between 400W and 560W for 1 meter square area.

If I try 350ma for example, using the same 4x4 grid I get 176W or if I use a 5x5 grid I get 275W which with my bad maths gets me 24.75W per sqft. If I try with the 5x5 using 240ma I get 180W so 16W per sqft. But I cant see how such a light would cover the canopy well (each covers 25cm squared). From my own testing I thought I would technicly need to run more cobs with lower amps.

If you want to pursue efficiency aggressively, I think the 72V CXA3590 at 350mA is pretty "cutting edge". 500mA is still on the cutting edge and 700mA would be standard for a very good DIY.

When we are talking about (dissipation) watts/ft², it very much depends on the efficiency. So it may be easier to think in PAR Watts/ft² (actual light). I use 30 dissipation Watts/ft² @ 46% efficiency so that is about 14 PAR W /ft². That works out to about 800ppfd. Maximum ppfd for cannabis would be 1500, but photosynthetic efficiency decreases as you approach the maximum so 600-1000ppfd is a good compromise IMHO.[/QUOTE]

 

[SupraSPL]

LMAO @ any month now

Good question, I use a pair of decent multimeters to test drivers and adapters so I can see the voltage and current at the same time and a kill-a-watt that can read tenths of watts. I put the ammeter on the device side (fan or LED) and the voltage reading from the adapter or driver side. That is because the ammeter adds a small voltage drop to the circuit and the adapter or driver is supporting that that load so we dont want to consider that waste.

So once you have that data, it is amps * volts = dissipation Watts
Then dissipation Watts divided by "power draw" Watts = efficiency



Most of the AC-DC adapters reach their maximum efficiency (~80% ideally) when they are loaded at about 80% of their maximum current. But with a small load they can be as bad as 30% efficient. Some of them will have a significant voltage droop as you increase the current so that is something else to look out for . For example it may say12V but actually put out 9-15V depending on the current load.

 

[kkman]

Both version of 3590 are the same efficiency-wise. 77V has twice as much Vf and half the current.

I don't think Supra was suggesting 3590 BB, he just posted comparison with 3070 AB. As you can see in that chart, 3070 AB is significantly more efficient at low-mid power. At max power they're equal. BD bin would be equal at slightly lower current.

As Supra said, even 350mA is "aggressively low current". What about 5x5 grid without the central COB? This way you could use 2x MW HLG-120H-C350B (or even A) with 12 3070's each. Provided that you wouldn't dim under 60%, it'd give you 14~26W/sqft with driver efficiency over 92%. Overall efficiency, including drivers, would be ~50% - an amazing number no other light can compete against.


Great find, thank you! Looks nice, mounting holes for 2 dimensions! Just ordered a few of them.

Ok lets take your example. I can run 24-25 cobs on two drivers, so not sure about your comment on no central cob. Either way. are you saying that I could dim down to 60% or thereabouts to 14 - 16W and the light would still provide a "good" flowering light. Let me ask this a simpler way, I currently would need 400W to light 1 sqmt with 16 z2 3070 cobs. If I went with a 5x5 array of 3070 ab or cxa3590 cb running 350ma I would expect to use 280W for the same area, would such a light provide a better light for flowering or have I just spent my money making somthing which wont penatrate the canopy or cover it properly. I lst so may not be a problem.

 

[alesh]

I agree with Alesh, the CXA3590 36V and 72V are equally matched on paper. The main difference is how it affects your choice of drivers. Generally speaking, it is cheaper to make a high voltage driver than a high current driver. For example we can get 280mA, 150V drivers for $7. That driver run a pair of 72V CXA3590s at 18W each, an expensive but viable current to run them at.

I mentioned the BB because it was "in stock" for a fair price. Sometimes resellers give the impression that they can provide a specific bin but when you go to order it they realize they cannot source it either and they cancel the order. Otherwise we could order the CXA3590 36V 3000K CB bin, which beats even the CXA3070 AB in terms of efficiency, cost and output. BUT if you do have a reseller than can actually source the BD bin, it would just about match the CXA3070 AB in terms of efficiency, cost and output, a very good choice.

View attachment 3327436





If you want to pursue efficiency aggressively, I think the 72V CXA3590 at 350mA is pretty "cutting edge". 500mA is still on the cutting edge and 700mA would be standard for a very good DIY.

When we are talking about (dissipation) watts/ft², it very much depends on the efficiency. So it may be easier to think in PAR Watts/ft² (actual light). I use 30 dissipation Watts/ft² @ 46% efficiency so that is about 14 PAR W /ft². That works out to about 800ppfd. Maximum ppfd for cannabis would be 1500, but photosynthetic efficiency decreases as you approach the maximum so 600-1000ppfd is a good compromise IMHO.

There's no CB bin in 3000K for 3590. BD is a top one.

And from what I can see from your chart, 3070 AB is a little more efficient than 3590 BD especially at these low current we're talking about, and also cheaper.

Agreed about PPFD. One has also to realize, that directly under COB, there is certainly much higher PPFD than the average.

 

[kkman]

Supa I prefer to use the 36V version of the 3590 as it makes swaping drivers with my 3070 simple.

I contact digi key and was told 4-8 weeks lead time from placing an order of 50 for the 3590 cb 36V.

From you comments above should I not take them at their word they can deliver the correct bin.

Having said that from what you said above I am not sure if I should just go for the 3070 ab bin's since I dont see how you could run any 3070 or 3590 so soft.

I currently would need 400W to light 1 sqmt with 16 z2 3070 cobs. If I went with a 5x5 array of 3070 ab or cxa3590 cb running 350ma I would expect to use 280W for the same area, would such a light provide a better light for flowering or have I just spent my money making somthing which wont penatrate the canopy or cover it properly. I lst so maybe not be a problem.

 

[SupraSPL]

True the PDF is not fully updated but the CB does exist. It makes sense because the Z4 used to be the top bin for the CXA3070 and then it was updated but the CXA3590 PDF was not updated with a new top bin. It made no sense that the top bin CXA3070 beats the top bin CXA3590 ( I agree with you , it does) so I expected a better CXA3590 to appear, and it did

 

[kkman]

There's no CB bin in 3000K for 3590. BD is a top one.

Sorry got my bins wrong
CXA3590-0000-000N00BD30F-ND

 

[SupraSPL]

KK, it would be awesome if they can deliver those, but I suspect not. It would be worth a shot though.

 

[SupraSPL]

As you can see the CBs were sold as BDs and at the BD price as well. The same thing happened to me once. I ordered a 100 pack of CXA3070 Z4s and got 100 ABs instead, for the Z4 price. Good stuff!

 

[alesh]

Ok lets take your example. I can run 24-25 cobs on two drivers, so not sure about your comment on no central cob. Either way. are you saying that I could dim down to 60% or thereabouts to 14 - 16W and the light would still provide a "good" flowering light. Let me ask this a simpler way, I currently would need 400W to light 1 sqmt with 16 z2 3070 cobs. If I went with a 5x5 array of 3070 ab or cxa3590 cb running 350ma I would expect to use 280W for the same area, would such a light provide a better light for flowering or have I just spent my money making somthing which wont penatrate the canopy or cover it properly. I lst so may not be a problem.

Only 12 3070's will run off that MW driver. You'd have to have only 24 COBs and I'd drop the one in the center.

And yes, 16 x 3070 Z2@700mA is almost equal to 24 x AB@350mA. 15 of Z2s is equal match.

@SupraSPL Yeah, right. They do exist but probably not readily for order. It's like P4 XP-E reds some time ago.
What do you think about new XP-E far red? Do you have any comparison of far red LEDs? I actually don't know its competitors, perhaps Ledengin, Everlight?

 

[SupraSPL]

Was there ever actually a 630 nm P4? I think it may have got confused because the orange-red comes in P4 bin and because the photo red is binned by wavelength using the P3 P4 and P5 designation, unintentionally confusing the buyers and even the sellers.

I will look into the XPE far red, did not even know there was one. It has been relatively easy to compare deep reds and far reds because they give us the output in mW. From memory the best so far were about 20% efficient (LED Engin)

 

[SupraSPL]

A quick analysis of the XPE far red top bin

@ Tj 25C
@350mA = .66Wdiss = .210W = 31.8% efficient
@700mA = 1.47Wdiss = - .404W = 27.5% efficient


@ Tj 40C (2.5% temp droop) -.015V
@350mA = .66Wdiss = .205W = 31.1% efficient

@Tj 50C (3.5% temp droop) -.025V
@700mA = 1.45Wdiss = - .39W = 26.9% efficient

Stands up very well to temp droop, just like the photo red.

 

[alesh]

Was there ever actually a 630 nm P4? I think it may have got confused because the orange-red comes in P4 bin and because the photo red is binned by wavelength using the P3 P4 and P5 designation, unintentionally confusing the buyers and even the sellers.

I will look into the XPE far red, did not even know there was one. It has been relatively easy to compare deep reds and far reds because they give us the output in mW. From memory the best so far were about 20% efficient (LED Engin)

Yeah, Cutter carried it for some time. It was probably close to 620 nm dominant wavelength selection, peaking prolly under 630 nm. If I am not mistaken, it was even in the data sheet for a while.

Yeah, its not hard to compare them, I was just lazy and tried you if you have some data on hand. The Cree one is 31.5% min@350mA@25°C

edit: TY, gotta smoke less and type faster. And then smoke

 

[PSUAGRO.]

A quick analysis of the XPE far red top bin

@ Tj 25C
@350mA = .648Wdiss = .210W = 32.4% efficient
@700mA = 1.47Wdiss = - .404W = 27.5% efficient


@ Tj 40C (2.5% temp droop)
@350mA Tj 50C = .648Wdiss = .205W 31.6% efficient

@Tj 50C (3.5% temp droop)
@700mA Tj 50C = 1.47Wdiss = - .39W = 26.5% efficient

good #s...........gonna see lots of diy flower triggers in the following months me thinks

 

[SupraSPL]

Ya we might as well run them very hard for that application. They are good up to 1A but I expect we could get away with more. I was able to run the Vero 10 at double its rated current with no trouble, for example.

 

[kkman]

KK, it would be awesome if they can deliver those, but I suspect not. It would be worth a shot though.

How long after they take the order and payments before I know if digi key will be able to deliver?

Only 12 3070's will run off that MW driver. You'd have to have only 24 COBs and I'd drop the one in the center.

And yes, 16 x 3070 Z2@700mA is almost equal to 24 x AB@350mA. 15 of Z2s is equal match.

@SupraSPL Yeah, right. They do exist but probably not readily for order. It's like P4 XP-E reds some time ago.
What do you think about new XP-E far red? Do you have any comparison of far red LEDs? I actually don't know its competitors, perhaps Ledengin, Everlight?

One more question. Since the hlg-120h-c350 max volt is 430 and I will be running 350ma or lower I thought 13*33 is 429V and once warmed up will run closer to 400V, why do you say 12 is the max for the driver.

 

[alesh]

According to PCT, @350mA 3070's are 33.62V typ. 13 * 33.62 = 437.06. You can have bad luck and easily end up with Vf 440V+. Or you can be lucky and they'll run ok. It's up to you if it's worth the risk.

inb4: "Warmed up, they're closer to 400V". Yeah, how are they gonna warm up, if they won't run off that driver?

 

[SupraSPL]

I am not sure, someone ordered the CXA3070 2700K Z2 or Z4 and the order got canceled eventually. I think it was @caretak3r ?