CreeCobLED
Member
Hey supra could you help me out with my questions above please?
Hey Supra
I have i dilemma, now i can get the heatsinks locally.
Now the dimensions are :
L:1000mm x W:100mm x H:40mm (Active) £32 each
L:1000mm x W:160mm x H:40mm (Passive) £48 each
Which ones should i go for ? dont forget i will be using 5 with 4 x 3590 on each.
I am thinking of using the 5 in 1200mm x 1200mm space which is half of the 2400mm x 1200mm tent and running one gavita on the other side for comparison and then hopefully swapping that side out to another 5 so i will have 40 x cobs running at 49-50% in the full space.
Now im hoping it wont be overkill and hoping the light spread will be uniform.
What do you think ?
Also what sort of heat will there be compared to the gavitas ?
Cheers
Hey Supra!@61.2%
(5) CXB3590 3500K CD 36V @ 1.05A (35.5W ea) $237.50
(1) HLG-185H-C1050 $65
177.5 dissipation W -> 68.9W heat ->
passive cooled heatsink 8268cm² -> 4.9"X36" $70
or
active cooled heatsink 2756cm² -> 3.5"X36" heatsink (for spread) $45 + 80mm fan + psu $10
(5) lenses $20
108.63 PAR W covering 6ft² =
$392.50 = $3.61/PAR W passive cooled
$377.50 = $3.48/PAR W active cooled
I come up with 811 PPFD averaged for 6 sq ft. Yes that should treat you very well in you 2X3. Good luck!Hey Supra!
Just hoping you can provide some more information on the average PPFD of this configuration (this one was missing from your original list)
Im trying to decide if i run with a four cob setup at 1.4 or 5 cob at 1.05a to replace my 400w HPS in a 2x3 and hopefully can get a good idea once i get that number. From what i understand the most ideal PPFD reading is going to be between 800-900 for flowering, would that be correct? Cheerssss
You can adjust for a tall canopy by increasing PPFD. So you could: increase current or run them even lower (350mA) and pack them in tighter. You could also use higher angle lenses or reflectors. I run mine at 500-700mA, no lenses on the center COBs and the ladies are as tall as 5.5 feet tall at times. I get about 18-24" of good bud in the upper canopy and strip out the lower branches, bend and side light any colas that try to get too tall. I also adjust the height of the heatsinks and the COBs are angled when necessary. Sounds like a like of work but I only spend a few minutes each month making adjustments.Love my 200w cxa3590 5k and my 400w cxb 3590 3k. I got like 20 XPE FR chips as well, but don't need to build them as of yet.
400w cxb3590 .7a great light, however maybe going 1A would be better as the .7 light penetration to the canopy ain't great.... Good but could be better.
.7a is best when you have your girls are LST.
Thanks supra, I'm actually leaning towards 6 cobs now @ 1.05a, don't want to cook my herbs, would this be a more ideal PPFD? Thanks for your time on this oneI come up with 811 PPFD averaged for 6 sq ft. Yes that should treat you very well in you 2X3. Good luck!
Is there an equivalent driver for just one cob at 1.05Ma with dimming? I'm in the process of building this for a veg light but also retro fitting a bloombox with cobs, so the post above this is not in relation to this one in regards to driver.I think you could use a CLG-60-36 with a single CXB3590 and get about 50% efficiency
Check this thread for choosing drivers https://www.rollitup.org/t/matching-drivers-and-cobs.883866/
LDH-45B-1050Is there an equivalent driver for just one cob at 1.05Ma with dimming? I'm in the process of building this for a veg light but also retro fitting a bloombox with cobs, so the post above this is not in relation to this one in regards to driver.
CXB3590 running at .7A is 50W in this case? What should the best canopy depth not exceed?Love my 200w cxa3590 5k and my 400w cxb 3590 3k. I got like 20 XPE FR chips as well, but don't need to build them as of yet.
400w cxb3590 .7a great light, however maybe going 1A would be better as the .7 light penetration to the canopy ain't great.... Good but could be better.
.7a is best when you have your girls are LST.
CXB3590 running at .7A is 50W in this case? What should the best canopy depth not exceed?
Depending on the kindness of strangers...And there you would be wrong, Sir. I was provided with the answers I was looking for within hours from this very community, for which I'm not only eternally grateful- means shit, really- but I fully intend to return the favor with interest in terms of showing the community what they've helped me build- AND what she'll do when you take her out and give her all she'll take.
I invite you to have a good look at my thread and make up your own mind about who I am and what I'm about. Link at the bottom of every post.
Always coming through with the goods bassman...
...And returning the favor. It's the highest of the old western ideals.Depending on the kindness of strangers...
HI guys & gals@CreeCobLED Thanks man, I would estimate 950 PPFD averaged for 2000W Gavita in your space, when the bulbs and reflectors are brand new. To match that with COBs in the same size space:
(5) HLG-185H-C1400A
(20) CXB3590 3500K CD
With drivers at max that would give you 875 PPFD averaged and should outyield the Gavita setup. LED dissipation would be about 1075W and power draw would be about 1150W with active cooled heatsinks.
For heatsinks you could use (5) 3.5"X40" bars with an 80mm fan in the center of each bar. You could put drivers on board the heatsinks or keep them all on a separate board. If you plan on dimming them often you could use HLG-185H-C1400B drivers with external POT dimmer. The A version has internal pot dimmer. Good luck with your build!
the equations i extrapolated from this graph and Supras charts for a 3590 3500k CD bin are:I am guessing that lamp mentioned above is using CPU coolers and generic 1.4A drivers. If they are genuine CREE, decent drivers, decently cooled and you had enough vertical space to get that light to spread out, that light would probably do a very good job. You might want to inspect the quality of the wiring to make sure it is as safe as possible.
@ttystikk Regarding running soft and how it affects PPFD, running your COBs lower can allow you to achieve higher intensity and more evenly spread PPFD, if that is your design goal. (as @nogod_ mentioned) It is somewhat complex to determine that actual cost of each system. When you run soft it takes less drivers and less heatsink to get the same job done, so that reduces some of the extra cost of buying more COBs. There are the direct electrical savings and that depends on the cost of electricity where you are. It may open the door to using passive cooling if that appeals to you and that implies remote drivers and increased heatsink adjustability. It may open the door to a partially solar powered grow. It may be ideal for grows that are limited on vertical space or shelf systems.
Because of the reduction in heat, depending on your setup there may also be direct electrical savings in environmental/AC cost But the most compelling advantage is, can you increase your total yield by reducing your heat load? If so then the extra cost of high efficiency can pay for itself in days (as @nogod_ described) . That is why I run the COBs at 730mA (25W ea) or lower when dimmed. That said, there is some uncertainty about exactly how much efficiency we are really getting. When I tested current droop I did see efficiency improvements all the way down to 4W per COB, but when I tried to quantify I realized the droop curve is compressed compared to CREEs so the values are not absolute after all.
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So if you do run them at 25W ea or lower, it might be best to approach that as experimental. That is why I recommend most DIYers to run them at ~50W ea.
with some extra driver headroom you dont need extra cobs. turn that shit up like freedom rock, manThis is a problem I prefer over the way around, Just lets me add more cobs, and I have a pair on the way