4.5X4.5 Tent... looking to do COB DIY

What would you guys put together I have a max of $1,500 to spend but if i can get away cheaper great - if not thats ok too!

I would like to maximize yield. I am leaning to the CREE 3590's but not sure which driver i should use to power them or how many of them i should go with. Can you all assist?

TIA

D
 

CobKits

Well-Known Member
heres a CXM22 build that will replace a 1000 DE HPS in the same space. 675 cob watts/725 wall watts. about $550 shipped if you use code "RIU" at checkout

cobs are assembled already to heatsinks. you just need to mount the heatsinks by cutting (or buying precut from a local metal supply place) 6 aluminum angle pieces and drilling 3 holes in each, no tapping
 

Attachments

newguy123

Well-Known Member
heres a CXM22 build that will replace a 1000 DE HPS in the same space. 675 cob watts/725 wall watts. about $550 shipped if you use code "RIU" at checkout

cobs are assembled already to heatsinks. you just need to mount the heatsinks by cutting (or buying precut from a local metal supply place) 6 aluminum angle pieces and drilling 3 holes in each, no tapping
I think you got the drivers wrong
3x hlg-185 would give 600W, did you mean hlg-240?
 

newguy123

Well-Known Member
the A models output about 225W at max voltage and current
I did not know, thanks.
Do you know what the output PPFD and joules would be with this setup? Also curious about the driver.. If i am going to order I want to make sure I get the correct items
The pffd for your 4.5x4.5 would be 683 if you take out 20% for the losses.
I will do another post showing the math
 

CobKits

Well-Known Member
Do you know what the output PPFD and joules would be with this setup? Also curious about the driver.. If i am going to order I want to make sure I get the correct items
in that space, real rough, at a distance where the light would be uniform (12-16") your ppfd would be about 800 umol/m2s, and very uniform. you can put more light in there, but the more light you put in, the less of a return you will get. 800-850W would be on the upper end which you could do with 16 cobs and it would be a touch more efficient. about $300 more
 

newguy123

Well-Known Member
You need to find the lumens/watt of your cobs at desired current but you first need to know how hard you will drive the cobs
675W/9cobs=75W per cobs
Their typical voltage is 54V so lets say 1.4A
If you go into the luminus website to find the lumen output
If you use the calculator found on their website http://www.luminus.com/calculator/
You will find that they will use 76.1W at 150.8Lumen/W
76.1W*150.8Lumen/W=11 460.8Lumen
Since you have 9 of them you will multiply by 9
11 460.8Lumen*9cobs= 103 147.3Lumen total
Now you need to divide by 325 to find the PAR Watt
103 147.3/325=317.376 PAR Watt
From what I know, each PAR Watt of the cxm-22 has 4.83umol/j
317.376 PAR Watt*4.83umol/j=1 532.92PPF

Now to get PPFD you need to convert it to 1sq meter
20.5sq feet is 1.904512 sq meter
1 532.93 PPF/1.904512 meter = 804 PPFD
 
Top