Build Using CLU048-1212C4 COBS. Advice Needed :-)

rocho

Well-Known Member
Last edited:

Baura

Well-Known Member
are you saying me to buy 1812 instead 1212?
Hell no, because I'm not qualified and I'm just planing to build my own DIY

The attachments are the 1812 80 and 90cri. Take a look at the photon output column. When you go from 80 to 90 cri the lumen output is "much" smaller but the photon output is almost the same.

It's a matter of how much blue, red and far red you want.

I believe the 3000k and 3500k 90cri have a smaller "peak" gap for 630-660nm. 90cri has more red after 660nm.

The 3000k and 3500k 80cri have big "peak gap" for 630-660nm. 80cri has less red after 660nm.

But how does those differences affects veg and bloom?
I hope this thread helps: DHP Presents Citizen Cob 1812 3500k 80CRI Vs 1812 3500k 90 CRI


Cheers
 

PiKasso

Member
I edited this:

1 CLU048-1212 @ 50W would rock that little tent very efficiently. A perfect spread would give you ~515 umol PPFD @ 1ft which is ridiculous. I would also recommend going for the 3500k with 90 CRI. 90 CRI citizen cobs have a broader spectrum and output more red and far red than the 80 CRI version.

Go for the 4000K if you need to minimize stretching, although the 3500ks got enough blue in my opinion.

Edit: 2 1212's even at 36W each would be around the 820 PPFD mark which is way ridiculously high unless you're an expert grower.
@eyderbuddy if you mixed in some 4K's in your lighting fixture to control stretch a bit, would you get 4K in 90 cri or 80cri to go with your 3500K 90cri?
 

eyderbuddy

Well-Known Member
@eyderbuddy if you mixed in some 4K's in your lighting fixture to control stretch a bit, would you get 4K in 90 cri or 80cri to go with your 3500K 90cri?
I'd always go with the 90 CRI simply because they offer a wider spectrum. In your case i'd be more worried about giving the plants too much blue.

If they're stretching too much with the 3500K have you thought if they're just a stretchy pheno? I Personally like how the 3500K spectrum looks so much like daylight, the white is really clear and doesn't tint everything orange, but after growing with 3500K for a few months i made another fixture with 3000Ks just for kicks and i've noticed a lot more growth with minimal stretching. I'm not saying that 3000K is better than 3500K, or 4000K for that matter, but it works for the strain i'm growing at the moment.

Stretching in my opinion is just more plant growth waiting for LST.
 

Stevooooo

Member
I'd always go with the 90 CRI simply because they offer a wider spectrum. In your case i'd be more worried about giving the plants too much blue.

If they're stretching too much with the 3500K have you thought if they're just a stretchy pheno? I Personally like how the 3500K spectrum looks so much like daylight, the white is really clear and doesn't tint everything orange, but after growing with 3500K for a few months i made another fixture with 3000Ks just for kicks and i've noticed a lot more growth with minimal stretching. I'm not saying that 3000K is better than 3500K, or 4000K for that matter, but it works for the strain i'm growing at the moment.

Stretching in my opinion is just more plant growth waiting for LST.
Old thread but how would a person calculate the ppfd of 7 clu048 1212 3500k 90cri in a 3x3
 

eyderbuddy

Well-Known Member
At 1400mA they run right around 50w each. So 350 total
TOTAL LED PPF output of 738.5 μmol/m^2/s in a space of 9.0 ft^2 or 0.836127 m^2.
Daily Light Integral (DLI) @ 1ft @ 12.0 hours = 38 mol.
Totaling at 39 Watts/ft^2.
Total Power consumption = 350.0 Watts. Monthly power consumption (12h on) = 128 kwh.
AVG PPFD @ 1.0ft = 883 μmol
AVG PPFD @ 1.5ft = 412 μmol

So basically:

Assuming 2.1 umol/watt since they're running at 50w each:

( 2.1 * 50 watt * 7 cobs ) / 0.836127 m^2. = 883 μmol
 

Stevooooo

Member
TOTAL LED PPF output of 738.5 μmol/m^2/s in a space of 9.0 ft^2 or 0.836127 m^2.
Daily Light Integral (DLI) @ 1ft @ 12.0 hours = 38 mol.
Totaling at 39 Watts/ft^2.
Total Power consumption = 350.0 Watts. Monthly power consumption (12h on) = 128 kwh.
AVG PPFD @ 1.0ft = 883 μmol
AVG PPFD @ 1.5ft = 412 μmol

So basically:

Assuming 2.1 umol/watt since they're running at 50w each:

( 2.1 * 50 watt * 7 cobs ) / 0.836127 m^2. = 883 μmol
Thanks for the math grand wizard lol. I’m good at math just don’t understand the conversions pertaining to light measurements. Not looking for a lesson or anything lol just saying.

883 is pretty high end for Mary Jane without adding co2 if I recall correctly.

Now that 883 is at 12” distance from canopy?

Edit: plus gotta love the power consumption. Cost me $16 for a month of 18-6 for the light. Fans will prob push it to $20+
 

eyderbuddy

Well-Known Member
Thanks for the math grand wizard lol. I’m good at math just don’t understand the conversions pertaining to light measurements. Not looking for a lesson or anything lol just saying.

883 is pretty high end for Mary Jane without adding co2 if I recall correctly.

Now that 883 is at 12” distance from canopy?

Edit: plus gotta love the power consumption. Cost me $16 for a month of 18-6 for the light. Fans will prob push it to $20+
A pleasure to help!

It's 12'' from the cobs. And of course, it lowers the further down you go, but with such high numbers i wouldn't worry that much distance. A good range would be 12-30'' from canopy, or as close as you can without burning the plants.
 

Sanitas Vibrationum

Active Member
Wow Those are really impressive!

Another question. What are my heat sink options for these cob's? I work in IT and have access to heatsink and fans. I know its a shot in the dark but could I possibly use those?
If you drive 1212's at 500ma (18W each) you can fit 4 chips on 140mm heatsink and save significant amoun of $. Heatsinks are the reason I don't build cobs anymore.Good luck man, these 1212s from Cobkits are amazing value.
 

CobKits

Well-Known Member
If you drive 1212's at 500ma (18W each) you can fit 4 chips on 140mm heatsink and save significant amoun of $. Heatsinks are the reason I don't build cobs anymore.Good luck man, these 1212s from Cobkits are amazing value.
the 133mm heatsinks i sell are drilled to accept 4 cobs in holders. ive run as high as 150W per heatsink with a tiny 12V fan on top
 
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