noob about to make a final decision. Please help.

Hi RIU,

Long time reader, first time poster, and finally pulling my finger out to build myself an indoor grow cabinet and am trying to finalise my lighting.

The internal dimensions of the cabinet measure 860mm wide x 450mm deep and it's 1200mm high (approximately 3.5' x 1.8' & 4' high) which will be used for flowering only. From the reading I have done I'm hoping 2 x CXB3590 should be sufficient to get the job done.

I'm in Australia so to keep costs down I'm trying to purchases as much as I can locally as postage is a killer if coming in from OS. So with my local limited choice, these are the COBs I have to choose from:

3000k
CXB3590-0000-000N0HBD30G
CXB3590-0000-000N0UBD30G

3500k
CXB3590-0000-000N0HCB35G
CXB3590-0000-000N0HCD35G

These are from Cutter Electronics and can be found here: http://www.cutter.com.au/products.php?filter=&cat=Cree+CXA/B35xx&pg=2

I've read that the difference between 3000k & 3500k is negligible so my inclination would be to go for the highest available bin, being CXB3590-0000-000N0HCD35G. (http://www.cutter.com.au/proddetail.php?prod=cut2810)

Am I on the right track? Will 2 of these COBs be sufficient for the size of my cabinet or would I be better of with one of the others?

Thanks.

Assuming you meant 3.5' x 1.8' x 4' tall which is about 6sqft. 25-50w per sqft rule of thumb. 150w would be the low end which would mean 3 cobs at 50w per cob. 4' tall means adding more cobs and using less power would make sense, keeping the cobs closer to the canopy, less heat in the small space. 6 cobs @25w each. 4 cobs @38w each. 3 cobs @50w each. It just so happens that the HLG-120H-C700(for 6 cobs) HLG-120H-1050C(for 4 cobs) and HLG-120H-C1400(for 3 cobs) would all work nicely at achieving 150w across your 6sqft.

All those numbers are on the low side of the spectrum but there's plenty of guys running CXB's at 25w per sqft.

2 of the 3500 CD bin cobs at 2.1 amps will give you around 600 PPFD, which isn't bad and would give you some nice results, but I would be inclined to use more emitters driven softer because of the height limitation. 3 3590s at 1.4 amps would be better, but better than that might be 5-6 3070s at 1.05 amps. That would really crank up the light intensity while still allowing you to get the plants close to the lights.

Oops! My bad.

Forgot to mention this will be a SCROG grow with the light height adjusted as required. Does that make a difference?

I'm hoping to get away with only needing 2 COBs.

Thanks for the quick replies.

Scrog will help but 4 feet is still pretty short. For the cost of 2 3590s you could get 3 3070s and run them at 1.4 amps. Similar cost, light and efficiency, just broken up in 3 instead of 2.

Rahz said:

Scrog will help but 4 feet is still pretty short. For the cost of 2 3590s you could get 3 3070s and run them at 1.4 amps. Similar cost, light and efficiency, just broken up in 3 instead of 2.

Click to expand...

You've sold me. 3 x 3050s sounds not only doable but possibly better.

Cutter.com has two 3050s that I can select from:

CXB3070-0000-000N0HAD30G (http://www.cutter.com.au/proddetail.php?prod=cut2816)
CXB3070-0000-000N0HBB35G (http://www.cutter.com.au/proddetail.php?prod=cut2813)

So should I base my decision on 3000k vs 3500k, or go with the better BIN of the two, of which I have no idea which is better as I have read that the BIN labelling is different for the 3050 & 3590, and I've only considered the 3590 up until now.

Thanks again.

Same basic scheme. I prefer the 3500K spectrum.

So I've been considering everything I have learnt over the last few weeks, and from the replies above I'm lead to believe that the height of my cabinet may be too small for the best space/lighting combination, so maybe I should change my plan once again. (so much to learn....)

The full size of the area I have to work with is actually 2270mm high (just short of 9 feet) and my plan was to build a continuous SCROG cabinet using Observe & Report's "More Money Than Brains" water cooled cabinet as a guide as detailed here: https://www.rollitup.org/t/more-money-than-brains-a-water-cooled-cab-build.802108/.

After reading through his build a few time's I plan on making the following changes:

• My flowering area will be at the base of the cabinet with the mother/veg area above. Ventilation will first pass through the flowering section, then through the mother/veg section and finally out of the cabinet. From what I read in his build thread, as well as elsewhere, I'm lead to believe that the extra heat & humidity from the flowering area would be beneficial to the mother/veg area.
  
• I will use Aluminium Cooling Tubes instead of PC cooling water blocks. Observe & Report noted that using square aluminium tubing as mentioned by epicfail would have been better than individual PC cooling water blocks. https://www.rollitup.org/t/more-money-than-brains-a-water-cooled-cab-build.802108/page-5#post-11117290

My plan was to divide my cabinet into 3 levels. Bottom level for flowering. Middle level for mother/veg and drying compartment, so the middle level will be split in 2 vertically similar to the bottom level of Observe & Report's cabinet. Top level for utilities such as electronics, water cooling equipment, filtration and extraction fan. The footprint of the cabinet is fixed at 860mm wide x 450mm deep, which I can't change, but I can change the height of each of the levels. I planned on allocating 1200mm for flowering, 800mm above that for mother/veg and the remaining 270mm for the utilities.

Assuming the utilities cannot be reduced in height from 270mm, that leaves me a total of 2000mm for flowering and mother/veg areas. What would be the best height/COB combination for the flowering section in order to best utilise my space & lighting source, taking into account that as the height of my flowering section increase, the height of my mother section decreases? Observe & Report's mother's seem quite happy with only 533mm of height, which means I should be able to increase the height of my flowering area from 1200mm to 1500mm and still have 500mm available for my mother/veg area. Would this be a better option?

Sorry. My head is mush from trying to figure out the best way to utilise the space I have & best use whatever lighting I decide to go with, so any guidance/advice from the experts here would be greatly appreciated.

Thanks again.

Final Question, and the deal is done.

I found an Australian supplier of Mean Well HLG-120C-1050 drivers saving me over $100 purchasing one from OS which means the budget allows for a total of four CXB3070s.

So will 4 x CXB3070 (CXB3070-0000-000N0HBB35G) and an HLG-120C-1050B driver work together for 6 square feet of space in a 4/5 foot cabinet?

Thanks.

Sounds like you've got a good plan going on. Only thing I might mention is since you will have almost 5 feet in the flower chamber it wouldn't be overboard to consider running the 3070s at 1.4 amps with a HLG-185. As long as you've got reasonable exhaust I don't think there will be any thermal issues. This would give you 200w of power -vs- 150, maybe around 30% more yield.

Also, you might be able to get a few more inches from the veg chamber by ditching the third compartment and mounting the drivers near the vent.

Cheers!

Rahz said:

Sounds like you've got a good plan going on. Only thing I might mention is since you will have almost 5 feet in the flower chamber it wouldn't be overboard to consider running the 3070s at 1.4 amps with a HLG-185. As long as you've got reasonable exhaust I don't think there will be any thermal issues. This would give you 200w of power -vs- 150, maybe around 30% more yield.

Click to expand...

Right now I'm trying to absorb the COB Efficiency Spreadsheets to try and understand the driver/COB relationship better.

After posting my previous post I wasn't sure if the HLG-120C-1050B was for the CXB3070 or CXB3570, or whether it could be used on both. I'm guessing it will work with both then?

If I understand you correctly, a HLG-185 will give me 1.4A over the four CXB3070 COBs? I'm trying to figure out how the HLG-120C-1050B would have run the CXB3070s so I can compare the figures in the COB spreadsheets. Is my thinking right? The penny hasn't quite dropped yet as to all this, but it will, so apologies for the dumb questions.

So while it all sinks in, could you quickly give me the numbers as to what the HLG-120 would have produced compared to the HLG-185?

Rahz said:

Also, you might be able to get a few more inches from the veg chamber by ditching the third compartment and mounting the drivers near the vent.

Click to expand...

With 1500mm (~5 foot) of flowering height I end up with 500mm (~2 foot) of height for my mother which will be kept nice and short. The chamber will be up to 450mm (~1.8 foot) deep and I have yet to determine its width. I'm looking to keep it relatively small. Basically big enough and lean enough in lighting to keep the mother healthy when I'm not veg-ing any clones from her, and when I am, then bright enough to handle it. Is that how I should be utilising the mother/veg chamber? I really haven't put too much thought into lighting for the mother/veg chamber as yet, but I'm more than happy for suggestions.

Whatever space I don't use next to the mother/veg chamber I plan on utilising for drying my grows before curing. Turn Observe & Reports cabinet upside down, and that's what I'm building, but I have to determine how wide to make my mother/veg chamber.

This is Observe & Report's cabinet upside down just in case my explanation is unclear.



Finally, the very top 270mm (~1 foot) of the cabinet, for its full 860mm width will house fans, filter, drivers, water, etc... This utilities section at the very top of the cabinet will be fed with the output air of the drying chamber, so it wont heat up, and the drying chamber in turn gets its air from outside the cabinet, so the drivers and electronics will be constantly cooled by air.

The 120-1050 will power 4 cobs 3070 or 3590 at about 36 watts each, so just under 150 watts total. The 185-1400 will power them at almost 50 watts each. You would have 33% more power. It won't equate into 33% more yield but it would be close to 33% more yield, maybe between 25-30% more.

As far as the veg chamber, it seems like you're duplicating something that's been successful so that's cool. As far as veg light intensity, you'll have plenty of time for the veg so I don't think there will be much need to crank it up. 6-8 par watts per foot would get the job done.

So this is what's available in Australia. Will it do? http://www.x-on.com.au/DetailsPage.aspx?MFRN=HLG-185H-C1400B&MFR=Mean Well&ID=3tSVel5D+iTh254cKbF/Ng==

It's $33 more than the HLG-120C-1050B, but it sounds like $33 well spent.

I'm sold. Thanks everyone, flowering lights have been decided.

Four CXB3070 LED COBS driven by a HLG-185H-C1400B.

Chuff420 said:

So this is what's available in Australia. Will it do? http://www.x-on.com.au/DetailsPage.aspx?MFRN=HLG-185H-C1400B&MFR=Mean Well&ID=3tSVel5D+iTh254cKbF/Ng==

It's $33 more than the HLG-120C-1050B, but it sounds like $33 well spent.

I'm sold. Thanks everyone, flowering lights have been decided.

Four CXB3070 LED COBS driven by a HLG-185H-C1400B.

Click to expand...

Get 3590's!!!

Airwalker16 said:

Get 3590's!!!

Click to expand...

That'll add another $100 and blow my budget.

What started out as two CXB3590s bought locally and a driver from OS totalling $300 has now ended up as four CXB3050s and a driver bought locally for $333. Given my cabinet dimensions, that would have to be an improvement, yes?

I had allocated $300 to LED & Drivers which would have worked out spot on with the HLG-120C-1050B, but Rahz's suggestion of using an HLG-185H-C1400B for a 33% increase in power for a 10% increase in cost was too hard to pass by, so I think I have got the best outcome given my budget and 6 square foot of space.

Unless someone can suggest a better "Bang for your Buck" combination.

Just out of curiosity, if I were to spend the extra $100 and upgrade to four CXB3590s, what would be the net gain in light, and would it be too much for my cabinet size?

Thanks again everyone for the great input.

Much appreciated.

I quickly put this together in Paint to give you a visual of the layout I plan on using.



Opinions?

Any unforeseen problems I may not have considered?

Thanks.

Chuff420 said:

Just out of curiosity, if I were to spend the extra $100 and upgrade to four CXB3590s, what would be the net gain in light, and would it be too much for my cabinet size?

Click to expand...

At 1.4 amps it would be about 7-8% more output. It would certainly pay for itself, just a matter of whether you want to spend the cash up front or not.

Chuff420 said:

That'll add another $100 and blow my budget.

What started out as two CXB3590s bought locally and a driver from OS totalling $300 has now ended up as four CXB3050s and a driver bought locally for $333. Given my cabinet dimensions, that would have to be an improvement, yes?

I had allocated $300 to LED & Drivers which would have worked out spot on with the HLG-120C-1050B, but Rahz's suggestion of using an HLG-185H-C1400B for a 33% increase in power for a 10% increase in cost was too hard to pass by, so I think I have got the best outcome given my budget and 6 square foot of space.

Unless someone can suggest a better "Bang for your Buck" combination.

Just out of curiosity, if I were to spend the extra $100 and upgrade to four CXB3590s, what would be the net gain in light, and would it be too much for my cabinet size?

Thanks again everyone for the great input.

Much appreciated.

Click to expand...

You'll get far more coverage and yield using more 3070's than you will with fewer 3590's. The only way I see of doing it cheaper is for you to use 4000k Vero 29's but I'm not sure how easily attainable they are down there.

On another note, if you add $100 to your cost to get 4 - 3590's then you have realize that you could also get at least 6 or 7 3070's for that price and have way better coverage and yield.

I'd stick with your plan that you and Rahz developed. It makes the most sense for your situation.

Im no expert but you could get a 1.4A driver and run 2 strings of 2530s @ 700mA each, 3-4 cobs / string and get a LOT of light cheap. Cutter has those LEDs for half price right now, 3000K 90cri. Nice thing about that is, if one string fails, the other string can handle full current without too much issue, so you wont blow everything if a single cob goes and the price/lumen is cheaper than the bigger chips cuz of the low price....

3500k 3590s at 66.09 rated up to 18000 lumens each, so 2 would be $132 and 36000 lumens, Spend the same amount on 2530s for 13.25 rated at 8000 lumens, so for the same price you could run 10 of these chips for a total of 80000 lumens.... Seems like a no brainer, I ordered 20 of them! These are max values, so real live output will be less, but the logic still applies. Also you could run all 10 from a single driver in 2 5 cob strings @ 700mA, make them dimmable and if you loose a cob/string, the other string still wont be over driven and in danger of frying.