Noob needs opinions on diy cob build

batrgrower

Well-Known Member
Alright so I've been running a perpetual system for about 6 months now with fairly good results. Currently I'm running 3 600w hps lights and 3 viparspectra 600w leds.

It's starting to get hot where I live and I'm having an issue with heat so I've been thinking about getting some cob lights built so I can get rid of the hot ass hps lights.

I'm completely new to the cob light scene but have been doing a lot of research and watching/reading stuff from supra and growmau5. Growmau5 recommends cree cobs so I did quite a bit of research on those. But today I ran across, what I think is, a killer deal on cobkits.com on some citizen cobs. They have these in 3000k for $9 each:

http://cobkits.com/product/citizen-clu048-1212-90cri-gen5/

So, my grow space is 12.5'x9.5'x8' tall and I have 3 "systems" in this space. Each one is approximately 50"x30". My thought is to build two 4' long rails, each with 5 cobs and running those 2 rails over each system. Does this sound like it would be good coverage?

I think I can run each 5 cob rail with this driver:

http://www.rapidled.com/mean-well-hlg-240h-c1400b/

And I plan on putting each cob on its own dedicated active Heatsink like these:

https://www.amazon.com/dp/B007BVCBOE/ref=cm_sw_r_cp_apa_ujKAzb6FCF2SK

Couple questions regarding the heatsinks. If I have 5 12v heatsinks on each rail, one for each cob, what is the best way to power them that won't leave me with wires running all over the place?

I hope this post is clear on what I'm trying to do. I'd like whatever input you guys want to give me, as I stated, I'm completely new to the diy cob world.
 

batrgrower

Well-Known Member
@CobKits will help you out on the 1212s... Have a look at www.timbergrowlights.com...
I was kind of thinking I'd like some non-biased opinions on the citizens, will @CobKits be able to do since they are affiliated with the site?

Also, I checked out timbergrowlights before and they have some cool stuff but I don't see anywhere that one buy individual components. Seems like the kits cost more overall due to convenience.
 

batrgrower

Well-Known Member
Alright, I talked a little with @CobKits about the chips he offers.

The l/w on the 1212s at 3000k is 149.
The l/w on the 1216s at 3000k is 128.
The l/w on the 1818s at 3000k is 141.

Im not sure what other specs I should be looking at on the spec sheet but based on this info it seems the 1212s are the best value especially since they are the cheapest chip.

Should I run 5 of those on one hlg240-1400 or am I missing something on the spec sheets where it makes more sense to spend a little more upfront on the 1216s or 1218s?

My thoughts on this are that I wouldn't be able to run all 5 of the 1818s on the 240, I would need to spend the extra cash on the 480.

I'd love to get opinions about this. Does the benefit of the 1818s with the 480 driver outweigh the extra cost compared to the 1212s or 1218s?
 
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nfhiggs

Well-Known Member
Alright, I talked a little with @CobKits about the chips he offers.

The l/w on the 1212s at 3000k is 149.
The l/w on the 1216s at 3000k is 128.
The l/w on the 1818s at 3000k is 141.

Im not sure what other specs I should be looking at on the spec sheet but based on this info it seems the 1212s are the best value especially since they are the cheapest chip.

Should I run 5 of those on one hlg240-1400 or am I missing something on the spec sheets where it makes more sense to spend a little more upfront on the 1216s or 1218s?

My thoughts on this are that I wouldn't be able to run all 5 of the 1818s on the 240, I would need to spend the extra cash on the 480.

I'd love to get opinions about this. Does the benefit of the 1818s with the 480 driver outweigh the extra cost compared to the 1212s or 1218s?
1212's for sure. I would run them at 1050 mA rather than 1400. Less heat, more efficiency. For the fans, there's really no way around running a bunch of wires. I use 12V 1 amp "wall wart" type power supplies for fans. One of those will power 5 fans easily.
 

xX_BHMC_Xx

Well-Known Member
I'm not so sure about the lm/w number you posted for the 1216s. Seeing as that is their newest Gen6 chip, wouldn't make any sense for them to be worse than the 1212s. What drive current is that at, 1400ma?

Also, for the coolers, go with the Arctic 11s. They're cheaper than the 64s, rated for more power, and have convenient mounting holes in the heat sinks so you can attach them more securely. When running a bunch of them in parallel, run one wire to the cooler, use a push-in connector or Wago to split that wire into two, then run one to the cooler and the other to the next cooler.
 

RandomHero8913

Well-Known Member
Alright, I talked a little with @CobKits about the chips he offers.

The l/w on the 1212s at 3000k is 149.
The l/w on the 1216s at 3000k is 128.
The l/w on the 1818s at 3000k is 141.

Im not sure what other specs I should be looking at on the spec sheet but based on this info it seems the 1212s are the best value especially since they are the cheapest chip.

Should I run 5 of those on one hlg240-1400 or am I missing something on the spec sheets where it makes more sense to spend a little more upfront on the 1216s or 1218s?

My thoughts on this are that I wouldn't be able to run all 5 of the 1818s on the 240, I would need to spend the extra cash on the 480.

I'd love to get opinions about this. Does the benefit of the 1818s with the 480 driver outweigh the extra cost compared to the 1212s or 1218s?
The chart of CobKits website states the 1216 are at 149lm/w not 128. He gave you the 90cri lm/w for the 1216.
 
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batrgrower

Well-Known Member
I'm not so sure about the lm/w number you posted for the 1216s. Seeing as that is their newest Gen6 chip, wouldn't make any sense for them to be worse than the 1212s. What drive current is that at, 1400ma?

Also, for the coolers, go with the Arctic 11s. They're cheaper than the 64s, rated for more power, and have convenient mounting holes in the heat sinks so you can attach them more securely. When running a bunch of them in parallel, run one wire to the cooler, use a push-in connector or Wago to split that wire into two, then run one to the cooler and the other to the next cooler.
Are you talking about these? There are a couple different variations but this is the only one cheaper than the 64.

ARCTIC Alpine 11 GT Rev. 2 CPU Cooler - Intel, Supports Multiple Sockets, 80mm PWM Fan at 22dBA https://www.amazon.com/dp/B002D2H9W0/ref=cm_sw_r_cp_apa_975Azb7QFAPND
 

xX_BHMC_Xx

Well-Known Member

RandomHero8913

Well-Known Member
Lumens per watt is a visual indicator. The difference in radiometric output won't be as pronounced for 90CRI.
You're correct but all the other numbers were based off of 80CRI chips and not 90s. That is why there is a discrepancy between the numbers.
 

Rahz

Well-Known Member
Lm/w does play a factor in the conversion to PPF though right? Or am I mistaken?
It does but each sample will have a different conversion factor. LER for VeroG7 3000K 80CRI is 332 and for 3000K 90CRI is 280. So 3000/80 at 166 l/w would provide the same energy per watt as 3000/90 at 140 l/w.

The math will be a little different for Citi chips but assuming the figures are similar:

1212 3000/80 149 l/w = 45% efficient
1216 3000/90 128 l/w = 46% efficient

If someone has the LER values for Citi the results would be more realistic.
 

xX_BHMC_Xx

Well-Known Member
It does but each sample will have a different conversion factor. LER for VeroG7 3000K 80CRI is 332 and for 3000K 90CRI is 280. So 3000/80 at 166 l/w would provide the same energy per watt as 3000/90 at 140 l/w.

The math will be a little different for Citi chips but assuming the figures are similar:

1212 3000/80 149 l/w = 45% efficient
1216 3000/90 128 l/w = 46% efficient

If someone has the LER values for Citi the results would be more realistic.
Got it, thanks Rahz. I'm working on digitizing the 1216 SPD. I'll post up some numbers here when I'm done.
 

batrgrower

Well-Known Member
1212's for sure. I would run them at 1050 mA rather than 1400. Less heat, more efficiency. For the fans, there's really no way around running a bunch of wires. I use 12V 1 amp "wall wart" type power supplies for fans. One of those will power 5 fans easily.
Where do we find the information about the chips being more efficient at lower amperage?

How do we make a calculation for any given chip to tell us what amperage to run it for maximum efficiency?
 

RandomHero8913

Well-Known Member
Where do we find the information about the chips being more efficient at lower amperage?

How do we make a calculation for any given chip to tell us what amperage to run it for maximum efficiency?
max efficiency would be as dim as can be. Obviously that ain't gonna work out too well for growing plants.

A good starting point is running the chips at half of their max current for middle ground efficiency.
 

batrgrower

Well-Known Member
1212's for sure. I would run them at 1050 mA rather than 1400. Less heat, more efficiency. For the fans, there's really no way around running a bunch of wires. I use 12V 1 amp "wall wart" type power supplies for fans. One of those will power 5 fans easily.
I could still use the 1400 driver but use the dimmer function to dim them back to 1050 right?
 
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