DiY LED - Cree CXA3070
- Thread starter SupraSPL
- Start date
captainmorgan
Well-Known Member
OK Supra,newb DIY question on the CXA307030HZ4's. You linked some ebay 50 watt 1500ma drivers for them. What kind of output would you get from them driving them at 1500 ma? Wouldn't driving them at 1900 to 2000ma be more of the sweet spot and how much would the change affect the efficiency?
PetFlora
Well-Known Member
No, it was in and out since I have not yet gotten the balls to DIM, but it looked good and the prices are for each.
I think is mentioned something like $35 min order, which should be great for the budget conscious DIYer
SupraSPL
Well-Known Member
Hey Captain, ultimately it is a matter of preference. You can get the same job done either way. High efficiency cost more up front for more COBs but you need less heatsink/drivers etc. Lower efficiency requires less COBs, but more dissipation watts/heatsinks/drivers/electricity/cooling/ventilation to get the same nugs.
I suspect those eBay drivers will run softer once they are warmed up, 1300-1400mA. At 1400mA the CXA3070 3000K Z4 is 39.3% efficient and dissipates 52W (20.4 PAR Watts = $3.33/PAR Watt all in cost). That is pretty tremendous and considering how small of an area it covers when you keep them in tight to the canopy that is a lot of photons in the canopy.
If you bump it up to 1.8A you get 36% and 69.7W (25 PAR Watts) which is still really awesome performance, but it doesnt save enough money to tempt me. It may not be possible to maintain a Tj of 50C so those numbers could be lower. Also, I can not give you an all in cost because I am not aware of any cheap drivers that can do the job.
I decided to run them at 900mA which is 43.7% efficient, dissipates 32W (14 PAR Watts) and cost $4.64/PAR W all in cost. There are some growers that are efficiency crazy and could run Z4s at 650mA with the $6 drivers. That would be 46.8% efficient, dissipate 22.6W (10.6 PAR W) and cost $5.75/PAR Watt all in cost. So that is 56% more efficient than commercial panels and still cost less.
For comparison, the Onyx Grow is probably the best commercial grow light. It dissipates 210W at 30% so that is about 63 PAR Watts. It cost $450 so that is $7.14/PAR Watt all in cost. These numbers are directly comparable because the Onyx grow uses 3000K Cree except the Onyx will suffer a significant additional penalty due to lens losses.
I suspect those eBay drivers will run softer once they are warmed up, 1300-1400mA. At 1400mA the CXA3070 3000K Z4 is 39.3% efficient and dissipates 52W (20.4 PAR Watts = $3.33/PAR Watt all in cost). That is pretty tremendous and considering how small of an area it covers when you keep them in tight to the canopy that is a lot of photons in the canopy.
If you bump it up to 1.8A you get 36% and 69.7W (25 PAR Watts) which is still really awesome performance, but it doesnt save enough money to tempt me. It may not be possible to maintain a Tj of 50C so those numbers could be lower. Also, I can not give you an all in cost because I am not aware of any cheap drivers that can do the job.
I decided to run them at 900mA which is 43.7% efficient, dissipates 32W (14 PAR Watts) and cost $4.64/PAR W all in cost. There are some growers that are efficiency crazy and could run Z4s at 650mA with the $6 drivers. That would be 46.8% efficient, dissipate 22.6W (10.6 PAR W) and cost $5.75/PAR Watt all in cost. So that is 56% more efficient than commercial panels and still cost less.
For comparison, the Onyx Grow is probably the best commercial grow light. It dissipates 210W at 30% so that is about 63 PAR Watts. It cost $450 so that is $7.14/PAR Watt all in cost. These numbers are directly comparable because the Onyx grow uses 3000K Cree except the Onyx will suffer a significant additional penalty due to lens losses.
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SupraSPL
Well-Known Member
One more thing to consider, even at 700mA the CXA3070 3000K Z2 bin is almost starving the top colas of my ladies. I have been trying to step up my fertilization but it takes time because I use recycled living organic soil and I have to let it cook-in for the most part. I have been trying to bridge the gap by watering in extra EWC, fish hydrolysate and blackstrap during veg. So if you run them at 1.4A or 1.8A be prepared for some seriously hungry ladies 
captainmorgan
Well-Known Member
OK Supra,since I got you on a roll. How about a CXA3070 30H Z4 driven by one of the ebay 1500ma drivers on one of these coolers and add 2-3 watt red LED's and 2-3 watt deep red LED's to the cooler driven at 350 ma or 500 ma? Do you think this heatsink would handle it ok? It's suppose to have 100 watts of capacity.
http://www.arctic.ac/us_en/alpine-11-64-plus.html
http://shop.stevesleds.com/Philips-Luxeon-ES-Standard-Red-3-Watt-LEDs-LuxeonRed.htm
http://shop.stevesleds.com/Philips-Luxeon-ES-Deep-Red-3-Watt-LEDs-Luxeon-ES-Deep-Red.htm
http://www.arctic.ac/us_en/alpine-11-64-plus.html
http://shop.stevesleds.com/Philips-Luxeon-ES-Standard-Red-3-Watt-LEDs-LuxeonRed.htm
http://shop.stevesleds.com/Philips-Luxeon-ES-Deep-Red-3-Watt-LEDs-Luxeon-ES-Deep-Red.htm
Bueno Time
Well-Known Member
Bit the bullet and ordered another 3070 cob, lpc-60-1400 driver, and two alpine 11 plus coolers. Going to be running two 3070s in my tent next round after this run with the 150 hps finishes up. I am at week 5 12/12 today so 5 more weeks or so until I finally get to play with some LEDs. I am pretty excited.
SupraSPL
Well-Known Member
Yes I think you could add some deep reds to the heatsink if they will fit. If you want to add reds I would recommend Cree XPE red P# bin. You can get them on stars from LEDGroupBuy, Cutter Electronics or the cheapest place I have found so far AC-Rc.net $2.60 on a 20mm star. That said, I have to wonder if it would make the most sense to just add the deep reds. You might even benefit from adding a Luxeon ES royal blue also.
Bueno Time
Well-Known Member
I am hoping for possibly more yield that would be awesome. I am hoping and expecting more density and maybe even quality increase.
I have got 101g on one run and 101.6g on another run using different genetics best yields under 150hps in my tent and last run 94g so if I can match or exceed my 150hps yeilds I could be close to the 1gpw area. I am running at 1400ma though so less efficiency per watt so my gpw may not be quite as high as it could be.
I expect good things though. The tent should run a little cooler than with the hps too being less wattage.
captainmorgan
Well-Known Member
OK Supra,I've decided on the 3 major components.
CXA3070 30H Z4
http://www.jameco.com/1/1/45675-lpc-60-1400-lpc-60-60w-single-output-switching-led-power-supply.html
http://www.arctic.ac/us_en/alpine-11-64-plus.html
I'm thinking 3 of these for a single plant in a 2.5' x 2.5' space,not sure 2 would be enough.
I still plan on adding 4 LED stars to each but that would be later on.
I still need a quality power supply to power the 3 fans or possibly 6 if I double the set up in a larger space,any suggestions?
CXA3070 30H Z4
http://www.jameco.com/1/1/45675-lpc-60-1400-lpc-60-60w-single-output-switching-led-power-supply.html
http://www.arctic.ac/us_en/alpine-11-64-plus.html
I'm thinking 3 of these for a single plant in a 2.5' x 2.5' space,not sure 2 would be enough.
I still plan on adding 4 LED stars to each but that would be later on.
I still need a quality power supply to power the 3 fans or possibly 6 if I double the set up in a larger space,any suggestions?
SupraSPL
Well-Known Member
Sweet setup! The 2A version of this PSU is my favorite so far, because it has a useful adjustable voltage range 8.4V-13V, decent efficiency 70-75% and cheap $5. If you run the fans at 8.4V the PSU should be OK to power 8-10 fans safely. If you run them at 12V it should be good for 6 fans. Just a heads up, always double check to make sure the fans are starting OK from a dead stop and cooled down PSU. I found some PSUs that could power a bunch of fans during testing, but could not start them from a dead stop and that would be a disaster for the COBs.
Also, if you are planning on running the fans at 12V and dont care about that type voltage adjustability, you can get higher efficiency 80-85% by using this style.
Also, if you are planning on running the fans at 12V and dont care about that type voltage adjustability, you can get higher efficiency 80-85% by using this style.
captainmorgan
Well-Known Member
I really like the 12v 5a 60w with two DC plugs from NJ,big enough to run two cabinets and a quick way to disconnect one with the DC slip connectors.
Supra,not sure if my math is right since this is all new to me.
With a CXA3070 30H Z4 driven at 1400 ma it should be around 51 watts and 8600 lm.?
Can you give me any other relevant #'s for it at 1400 ma?
Should I us a 2 amp fuse for this?
Supra,not sure if my math is right since this is all new to me.
With a CXA3070 30H Z4 driven at 1400 ma it should be around 51 watts and 8600 lm.?
Can you give me any other relevant #'s for it at 1400 ma?
Should I us a 2 amp fuse for this?
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mauricem00
Well-Known Member
two dumb newbie questions. 1st any opinions on this http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=291048983583 2nd running a mix of warm white/cool white leds at 104 lumens per watt. how many watts per square foot of growing area is recommended. new to diy leds. have grown with T5s but want to experiment with leds
Bueno Time
Well-Known Member
Dont get that ebay COB in the link you posted. A couple dollars more will get you a really good cree cxa3070.
mauricem00
Well-Known Member
at this point I am using cheap leds to test different "mixes" once I find a mix I like then I will invest In good diodes.I am currently leaning toward the R/W/B blend to try and match the targeted action spectrum (SPD) more closely.and old study I found seems to provide some guidance in this area http://www.plantphysiol.org/content/46/1/1.full.pdf I think with the right SPD good growth and yield can be achived with a lot less energy and corresponding decrease in cost. from the attached graph it appears that there is a point of diminishing returns in term of intensity as well which is also a factor in developing lights. any opinions on using violet (420-430 nm) LEDS to hit the chlorophyll A receptors? they respond to 660 nm as well but have 2 excited states and deep blue or violet in needed to hit the 2nd state.
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WDIK
Active Member
Are you talking about how you like your women?
Sorry, that was a hanging curveball right over the plate.
mauricem00
Well-Known Member
you could try "SMALL " CFL reptile lights with just a clamp type reflector. to much UV would be bad for the plants and your eyes. some have used led light bulbs from home depot as side lighting om T5 grows and report increased yields.so your hybrid approch is a viable option. I would stick with 6500k or 10000k T5s. and be careful with uv lights
mauricem00
Well-Known Member
I hate to disagree with you but I have designed and built linear power supplies and even rewound transformers fro old microwave ovens and linear power supplies are not efficient. they are designed to produce a clean stable output. PWM voltage or current regulation is much more efficient. just compare the size of the heatsink on both types of power supplies to see how much heat they are designed to dissipate.constant current would be better because the forward drop decreases as the temperature goes up and with constant voltage well regulated supplies this can lead to thermal runaway that could destroy the diode. constant current supplies track this voltage drop so total input power declines as temperature rises. providing some protection for the diode.