Another Cree CXA3070 DIY Thread
- Thread starter captainmorgan
- Start date
captainmorgan
Well-Known Member
How hard were you thinking of driving them? I do 1 plant on a 3x3 with 7 to 9 weeks veg,on a 2x2 1 plant with 6 to 8 weeks I would think, but you could probably veg for less if you set a screen real early.
PetFlora
Well-Known Member
They re either growing up or sideways.
The amount of time should be ~ the same
Perhaps 2 weeks more for all the colas now reaching up
The increased yield is worth it
captainmorgan
Well-Known Member
Day 49,the Deathstar is starting to put on some good weight now,but the LSD puts her to shame.
Attachments
captainmorgan
Well-Known Member
Forgot to ask what bin you have. I think 4 of them at 1.4a in a 2x2 is complete overkill,thats over 50 watts a sq/ft. The two plants going right now were only about 16 inches tall on a short veg when they went under my 3000k Z4's at just under 28 watts a sq/ft and the pics speak for them selves. There's a point at which more light doesn't mean more yield,my guess is that more than 30 watts a sq/ft of Z4's starts to have diminishing returns.
captainmorgan
Well-Known Member
Here's the numbers for Z4's.
medicinehuman
Well-Known Member
I just switched some 3000k Z4's to drivers at 800mA FROM 1400, I measure 72.3w with two z4s, two drivers and two fan's and controllers, One plant under it went 5 week's at 1400mA before changing. See how it go's, the 20x24 closet is filled up nicely now. I have a feeling that I will get a gram a watt with these Cali Jacks. Not sure of actual light watts, maybe 32? each.
Some old fashioned bud porn.
Some old fashioned bud porn.@captainmorgan
Hey captainmorgan,
can you upload the efficiency-table of the CXA 3070 Z4? I would like to understand the calculations.
Greetings and thx
SupraSPL
Well-Known Member
First we calculated the minimum lumens/Watt which depends on how hard you run it and how cool you can keep it. Then we convert from lumens/Watt to electrical efficiency (%) by using the LER for the 3000K curve. Once you have the electrical efficiency you can start to get an idea how a lamp will really perform, but you still have to consider the photosynthetic efficiency of the curve as well as the photomorphogenic effects (how much blue and ratio of red/far red/infrared)
All those things considered, the CXA3070 3000K Z4 is among the very best you can get, but currently only the Z2s are available as far as I know (digikey)
All those things considered, the CXA3070 3000K Z4 is among the very best you can get, but currently only the Z2s are available as far as I know (digikey)
Observe & Report
Well-Known Member
A Z2 CXA3070 is $40 but a Vero-29 has dropped to $30.70
With $9.30 difference, you have to save 62 kWh at $0.15/kWh to break even. At 50W on a 12-hour schedule you're talking 219 kWh per year. To break even before 3 years the Z2 has to be 9.4% more efficient than the Vero-29. Most CXA3070 users buy a holder, raising price by another buck or two.
With $9.30 difference, you have to save 62 kWh at $0.15/kWh to break even. At 50W on a 12-hour schedule you're talking 219 kWh per year. To break even before 3 years the Z2 has to be 9.4% more efficient than the Vero-29. Most CXA3070 users buy a holder, raising price by another buck or two.
Observe & Report
Well-Known Member
I'm pretty sure Mr. Flux analyzed the spectra and found that Veros are more red than CXA and 3500K Vero is closer to 3000K CXA. http://rollitup.org/t/cree-cxa-analysis.743645/#post-9761101
aha then i should better get one 5000K and then 2x 3000K . Look at this nice heatsink i found at digikey: http://www.digikey.com/product-detail/en/NX300158/1061-1153-ND/4215390 . Only 13 bucks and has already tapered holes so just screw in the led 
but you have to buy extra fan i guess.
but you have to buy extra fan i guess.