Have any of you DIY COB Growers finished a crop under 1000W DE HPS? - POLL

Have any of you DIY COB Growers have actually finished a crop under 1000W DE HPS?

  • Yes

    Votes: 32 29.1%

  • No

    Votes: 78 70.9%
  • Total voters
    110
ttystikk

ttystikk

Well-Known Member
since1991 said:
You a bad mo fuhkuh Stikk!!!! I mean that too!!!!
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So here's the dealio on da COB efficiency game; when you underdrive an HID lamp, it's losing efficiency and lifespan because the arc is not being driven to the expected temperature. Low temperatures are the enemy of lamp life.

COB LED is totally different; run it at full power and you get the listed efficiency and lifespan. If you give it less power than the design specification calls for, the chip will produce less light, but it does so MORE efficiently- and it lasts longer! In addition, running them cooler also increases efficiency. This is the opposite of what light bulbs do.

Example; CXB3590 CD bin running at the full 100W is about 44% efficient, that is, 44% of the watts the chip is being fed come out as PAR (Plant Active Radiation), and what's left is heat.

Run the same chip at just 50W (voltage stays the same, cut the amps in half) and now it converts watts into PAR at 56% efficiency, a full 25% improvement! Spectrum shift in COB chips is negligible.

Run it at 23W and it's 64% efficient. Notice how you'll need more chips for a given wattage load at each step, this is why more efficiency costs more money, at least up front. Every COB LED chip works the same way, but some work much better than others and every chip has its own unique 'current droop' (the name of the phenomenon) curve. Thus, we can thank lots of people on these boards for doing the tedious work of finding out which chips perform better when underdriven like this.

So in a sense, yes, there's a dial. Dial your watts to get your desired efficiency.

And here you thought I was just jerkin' yer chain, didn't ya laddie?
 
CaliWorthington

CaliWorthington

Well-Known Member
ttystikk said:
First you say you don't think COB LED would be good for larger grows, then you say you're going to cram 40 into a tent, lol

I'm putting almost 100 in a small room and I think your assertion about COB LED's lack of suitability for commercial use is incorrect. Not only can they be used this way, they will be, soon, in mass numbers. The economics of the industry demand it.

Chips are getting better and less expensive all the time. Want bright? Up to 2400W! Advertised RIGHT HERE on RIU! want efficient? Guys on here have already built 70% efficient panels and they'll only get cheaper and more accessible as chips keep getting brighter and cheaper.

Two years and it will be hard to sell HID lighting. Five years and you can't give it away.

EDIT: me and my wordiness made me late to this dogpile, lol
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Almost 100 COBs will be awesome! What mA are you going to run them at?

I may be wrong. If HID is gone in 5 years I'll eat my words. Supra said the CXB series are approaching the limits of thermal efficiency, so I don't know that COBs are going to keep evolving at this pace. But if the price comes down enough, I'm sure someone will be the first to do a massive COB warehouse grow.

Or maybe it will be mandated. Just imagine the reaction of HID growers being told they have to use LED, or some other more efficient type of lighting. It could happen.

swagslayer420 said:
I got about 2.5 ft and its stays 76-85f/ 30-55RH in a 4x4 tent my hood is aircooled with with 6' fan exhausted out of room no a/c running right now and getting amazing results. I use all technology for my own study to draw my own conclusion on my results and methods used, I am not afraid to try anything once in this industry but if I get screwed ill never use it again.
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Very cool. I think what they're saying is, at less than 3-5' you're not quite optimizing the brightness and footprint of the fixture. I've heard of others using them at closer distances too though. I've also heard of people cooking their plants with Gavitas. Some people say just dial down the wattage, but that sounds like not the greatest idea according to what ttystikk is saying. I read the same thing, DE bulbs need to run hot.

I just recently installed drip tables. They're pretty low, but I don't think there's enough clearance for DE HPS. This air cooled CMH setup might be nice though. Like you, I'm willing to try it once anyway.
 
since1991

since1991

Well-Known Member
ttystikk said:
So here's the dealio on da COB efficiency game; when you underdrive an HID lamp, it's losing efficiency and lifespan because the arc is not being driven to the expected temperature. Low temperatures are the enemy of lamp life.

COB LED is totally different; run it at full power and you get the listed efficiency and lifespan. If you give it less power than the design specification calls for, the chip will produce less light, but it does so MORE efficiently- and it lasts longer! In addition, running them cooler also increases efficiency. This is the opposite of what light bulbs do.

Example; CXB3590 CD bin running at the full 100W is about 44% efficient, that is, 44% of the watts the chip is being fed come out as PAR (Plant Active Radiation), and what's left is heat.

Run the same chip at just 50W (voltage stays the same, cut the amps in half) and now it converts watts into PAR at 56% efficiency, a full 25% improvement! Spectrum shift in COB chips is negligible.

Run it at 23W and it's 64% efficient. Notice how you'll need more chips for a given wattage load at each step, this is why more efficiency costs more money, at least up front. Every COB LED chip works the same way, but some work much better than others and every chip has its own unique 'current droop' (the name of the phenomenon) curve. Thus, we can thank lots of people on these boards for doing the tedious work of finding out which chips perform better when underdriven like this.

So in a sense, yes, there's a dial. Dial your watts to get your desired efficiency.

And here you thought I was just jerkin' yer chain, didn't ya laddie?
Click to expand...
Wow. You sumbitch....actually u just dropped knowledge in a paragraph. I get it. Well a couple. Lemme digest this shit fer a sec. So much broseph...so much.
 
swagslayer420

swagslayer420

Well-Known Member
=Very cool. I think what they're saying is, at less than 3-5' you're not quite optimizing the brightness and footprint of the fixture. I've heard of others using them at closer distances too though. I've also heard of people cooking their plants with Gavitas. Some people say just dial down the wattage, but that sounds like not the greatest idea according to what ttystikk is saying. I read the same thing, DE bulbs need to run hot.

I just recently installed drip tables. They're pretty low, but I don't think there's enough clearance for DE HPS. This air cooled CMH setup might be nice though. Like you, I'm willing to try it once anyway.
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correct I am losing footprint the hood puts out a 6x4 footprint. My goal is that footprint with 9-10ft ceilings
 
ttystikk

ttystikk

Well-Known Member
frica said:

Is it me or could the testers here have pulled the Gavitas closer to the plants?
The Gavitas look like they could have been pulled at least 10 inches closer and some of the LED plants also got illuminated by the Gavitas
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Loved this video because they did three brands of DE fixtures- and showed just how big of a performance gap there is between them.
 
since1991

since1991

Well-Known Member
I just tried explaining to my gal how much money we could save and get an even bigger harvey....its all greek to her. Let her just chop and trim shit. But iam on it man...cob is the future....there is no doubt.
 
ttystikk

ttystikk

Well-Known Member
since1991 said:
I just tried explaining to my gal how much money we could save and get an even bigger harvey....its all greek to her. Let her just chop and trim shit. But iam on it man...cob is the future....there is no doubt.
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I'm sandbagging, too. I have even more great ideas about how to make them work even better and cost less.
 
ttystikk

ttystikk

Well-Known Member
CaliWorthington said:
Almost 100 COBs will be awesome! What mA are you going to run them at?

I may be wrong. If HID is gone in 5 years I'll eat my words. Supra said the CXB series are approaching the limits of thermal efficiency, so I don't know that COBs are going to keep evolving at this pace. But if the price comes down enough, I'm sure someone will be the first to do a massive COB warehouse grow.

Or maybe it will be mandated. Just imagine the reaction of HID growers being told they have to use LED, or some other more efficient type of lighting. It could happen.
Click to expand...
Power companies are already giving out credits for better lighting like candy. When they see what COB LED can do, I suspect they might consider just buying the chips for the growers outright, lol

COB LED has already crossed the Rubicon of cost competitiveness vs HID, that is, right now it's cheaper for a warehouse operator to switch to COB LED than to continue paying for HID. That savings will only get bigger over time.


Even if COB LED doesn't get any better- no way, but what if- they'll still be coming down in price. They're already better than HID so the only remaining barrier is initial cost. They'd STILL crush HID; it's only a matter of time.

I'm running my chips at 54W, 4 to a Meanwell HLG-185-C700B. My chips are 72V and the extra 4W per chip is coming from the driver because the remote dimming circuits are capped off. The last 8W is driver inefficiency, so each module pulls 224W. I round to 225W to make the math easier.

4 of these modules will light one plant on one 4' wide by 6' tall trellis panel.
 
ttystikk

ttystikk

Well-Known Member
since1991 said:
What is the apex of the cobness? 3590 bin rite? God iam so lost. Drivers?
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I'm the wrong guy to ask, lol

CXB3590 is the chip name. They come in different bins for brightness at a given drive current, so these bins relate directly to efficiency. Right now, CD bin is the highest available for the CXB3590. That simply can't last forever.

Drivers come in all sorts of sizes, to match various numbers of chips at various drive currents. This is how people match their lighting to their specific situation.
 
nevergoodenuf

nevergoodenuf

Well-Known Member
You can also run them at 240v if you want them to run cooler. I now have a 30 Amp 240 light controller and notice all my drivers are running cooler.
 
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