BM9AGS
Well-Known Member
Would we want to match ppf or ppfd?
Have any of you DIY COB Growers finished a crop under 1000W DE HPS? - POLL
- Thread starter OneHitDone
- Start date
Airwalker16
Well-Known Member
It could absolutely NOT be from seeds. Accurate side by sides MUST BE taken by clones from the same plant that grew roots at the SAME time.
Airwalker16
Well-Known Member
If you had 1 cob on center of every Sq foot you were illuminating then I'd absolutely want stellas.
OneHitDone
Well-Known Member
I thought we were talking total raw photon output of lamp source, not Par graphs which can be all over the place and misleading depending on distance etc
OneHitDone
Well-Known Member
This has been talked about and hinted about by several of the cob panel builders advertising here but still - where is the sphere test on a cob panel?
ttystikk
Well-Known Member
There's no doubt left that COB LED is more efficient in terms of umol/watt than HID. Likewise, there is no longer a debate about whether COB LED emits a better quality spectrum than HID. From here, it's just about cost.
I can tell you from personal experience that COB LED gives up quality to no HID bulb, either.
I'm currently working to answer questions about scalability and related economies.
I can tell you from personal experience that COB LED gives up quality to no HID bulb, either.
I'm currently working to answer questions about scalability and related economies.
bassman999
Well-Known Member
most of them time
Same amount of light, but more concentrated and less stray.
In my case might not be better as I have a short tent, and cobs are 6"-9" from tops usually
bassman999
Well-Known Member
Hey Bobby!
Not much up here same old, flowering 4 B.D. and 2 Clementine in my 2x4 with 12 cobs @about 30 watts each.
Goal is 1.4 GPW, last round I got 1.2544 gpw
I am running (2) HLG-240H-42B, and have them dimmed to about 185 watts each
One is running (6) CXA3070s 3000K, other is running (6) CXB3590s 3500K
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ttystikk
Well-Known Member
Remember to factor in cost of cooling each separately, they'll have different HVAC needs. And yes, it does count, because without it your DE is basically worthless.
ttystikk
Well-Known Member
It won't be fair at all.
The results will be that 800W of COB LED will mop the growroom floor with the DE, and will need less cooling wattage while it does it.
wietefras
Well-Known Member
They put a 1000W Gavita DE on a integration sphere and ended up with around 1750umol/s. ie 15% loss on the reflector.
Gavita designed a tent together with Mammoth to perfectly match a single fixture (and also one for two fixtures). The PPFD in this tent was measured at around 800umol/s over the 2m2 surface. So after reflector and wall losses you are left with around 1600umol/s from that bulb.
So around 700W of CXB4590 CD or CXB3070 BB would even suffice for producng the same amount of light
Gavita designed a tent together with Mammoth to perfectly match a single fixture (and also one for two fixtures). The PPFD in this tent was measured at around 800umol/s over the 2m2 surface. So after reflector and wall losses you are left with around 1600umol/s from that bulb.
So around 700W of CXB4590 CD or CXB3070 BB would even suffice for producng the same amount of light
Airwalker16
Well-Known Member
How many cobs though for that 700W's
OneHitDone
Well-Known Member
Ya, make sure you put that DE in an AC/DE hood and let's see the difference in cooling costs
BM9AGS
Well-Known Member
So just match 1750umol/s with leds?
16 cxb3590 at 50 w would make 790 ppfd in a 5x5 based on the DIY COB LED CALCULATOR
bassman999
Well-Known Member
The cxa3070 didnt like the 36V drivers at higher current and so I went with 42V.
I had just CXA cobs in the beginning
Now that I am running them so soft the 36V would work, but Im not spending anymore $$$
ttystikk
Well-Known Member
The COB LED array would be much more efficient at distributing the light evenly, plus spectrum output puts the DE on the trailer.
BM9AGS
Well-Known Member
I know brother.... My friend is a hid guy and I'd like to do this to see for ourselves and also put it on here for something people can reference. I just need somewhere to get 30 clones.....hmmm.
Id do 2 5x5 foot grow rooms with about 15 clones each.
Personally I think it would be the most simple to do 1000w of each light with clones then if the cob produced 20% more you'd know they're 20% better.
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