Cob drive amperage & effective penetration

Checked it out and just as I thought it isnt really a thing... If you have a tight canopy (scrog or just a trellis) you wont have any light over 100PPF going through the first layer of leaves making this for all intents and purposes a pointless thing to bring up. The numbers were the same for HPS, DE HPS, and COBS.

The only way to get more into the canopy is side lighting and not having a hot spot (IE multiple LES) Which might be a good idea.

Now if you have a stretchy strain then the more PPF/D you have the farther down the light will go, but that doesn't necessarily correlate to more wattage. That "penetration" only exists because there is space for light to pass through (those stretchy strains), but with a proper canopy thats pointless anyways.

Long story short, More PPF/D in a area (to a certain level) is what makes penetration a thing. its not directly dictated by power or how many watts you're pushing, but rather the usable light that is being pushed on the canopy level.
 
After all the input, gonna go with 2x 700ma drivers and 16x CXB 3590's. for the 4x4 space. Initial costs will be higher but hopefully I can make up for it in sheer efficiency. 400w total (was tempted to go 600w but I think that might be overkill)
 
Nugtorrent said:
After all the input, gonna go with 2x 700ma drivers and 16x CXB 3590's. for the 4x4 space. Initial costs will be higher but hopefully I can make up for it in sheer efficiency. 400w total (was tempted to go 600w but I think that might be overkill)
Click to expand...

Its not bad but if you can afford it I would suggest aiming for around 850 PPFD. If this is the one for veg thats fine. heres that light youre talking about.. its efficient AF.

CXB3590CD36V3500K 16 COBS @0.7A ON 5.88 PROFILE HEATSINK
16 SQ.FT. CANOPY 92% EFFICIENT DRIVER @15 CENTS PER KWH
Total power watts at the wall: 397.83
Cobs power watts: 366
Total voltage forward: 524
Total lumens: 75905
Total PAR watts assuming 10% loss: 211
Total PPF: 981.15
PPFD based on canopy area: 660.06
PAR watts per sq.ft.: 13.19
Cob efficiency: 64.01%
Power watts per sq.ft.: 22.88
Voltage forward per cob: 32.72
Lumens per watt: 207.39
Heatsink riser thickness / number of fins / fin's length: 0.27in/14/1.0in
Heatsink area per inch: 260.01 cm^2
Total heat watts: 132
umol/s/W / CRI: 4.65 / Estimated
Heatsink length passive cooling @120cm^2/heatwatt: 61 inches
Heatsink length active cooling @40cm^2/heatwatt: 20 inches
COB cost dollar per PAR watt: $3.61
Electric cost @12/12 in 30 days: $21.98
Electric cost @18/6 in 30 days: $32.72
Cost per cob: $47.62
Heatsink cost per inch cut: $1.74
Total cobs cost: $762
Total heatsink passive cooling cost: $106
Total heatsink active cooling cost: $34

If you step up to the 1.05A driver you will get there.


CXB3590CD36V3500K 16 COBS @1.05A ON 5.88 PROFILE HEATSINK
16 SQ.FT. CANOPY 92% EFFICIENT DRIVER @15 CENTS PER KWH
Total power watts at the wall: 618.48
Cobs power watts: 569
Total voltage forward: 542
Total lumens: 110955
Total PAR watts assuming 10% loss: 315
Total PPF: 1464.75
PPFD based on canopy area: 985.4
PAR watts per sq.ft.: 19.69
Cob efficiency: 61.5%
Power watts per sq.ft.: 35.56
Voltage forward per cob: 33.85
Lumens per watt: 195.0
Heatsink riser thickness / number of fins / fin's length: 0.27in/14/1.0in
Heatsink area per inch: 260.01 cm^2
Total heat watts: 219
umol/s/W / CRI: 4.65 / Estimated
Heatsink length passive cooling @120cm^2/heatwatt: 101 inches
Heatsink length active cooling @40cm^2/heatwatt: 34 inches
COB cost dollar per PAR watt: $2.42
Electric cost @12/12 in 30 days: $33.9
Electric cost @18/6 in 30 days: $50.6
Cost per cob: $47.62
Heatsink cost per inch cut: $1.74
Total cobs cost: $762
Total heatsink passive cooling cost: $176
Total heatsink active cooling cost: $59
 
Damn dude that is legit. Which driver are you using for your second example? I have some notes on the Mean Well 185h-c1050 that I took off growmau5's videos, & he was saying at 179v forward voltage it could power 5 CXB3590's, and the HLG 240hc1050b could power 6. Seems I would be short running 3x 185h-c1050's by a single cob?

Your post is awesome by the way thanks.
 
Nugtorrent said:
Damn dude that is legit. Which driver are you using for your second example? I have some notes on the Mean Well 185h-c1050 that I took off growmau5's videos, & he was saying at 179v forward voltage it could power 5 CXB3590's, and the HLG 240hc1050b could power 6. Seems I would be short running 3x 185h-c1050's by a single cob?

Your post is awesome by the way thanks.
Click to expand...

The LED calculator really helps, check it out.

As for the driver, Look for what ever one will come closest to a whole number or get a dimming one if you prefer then you can adjust to how efficient you want to run them.
 
OLD MOTHER SATIVA said:
yes i understand that..and to be fair ...nothing penetrates a leaf..it penetrates where there are openings

my post was a question..because i don't know for sure..and i am not sure you know the answer [either]
Click to expand...

certain wavelengths will indeed "penetrate" the leaf biological material itself not just "empty spaces" , that is correct.

SDS pointed this out a while ago and is one reason why green light will drive photosynthesis lower in the canopy...because the red and blue wavelenghts mostly seem to be absorbed by the top parts of the canopy....
 
I haven't read, but good damn...

PPF is the raw amount of micromoles a second, so the amount of photons in a second and the energy it produces.... umol/s
[It is not height dependent, but heat will be......]

PPFD is a function of PPF in space.. 1 m^2 to be exact....


If you have 500ppfd from 700ma of power it will equal 500ppfd provided by 1050ma or 1400ma etc....


@CobKits

please read this till your eyeballs bleed...I really still cant believe you don't know these calculations.....
http://www.inda-gro.com/IG/sites/de...ing-resource/2-Understanding PPF and PPFD.pdf
 
Abiqua said:
certain wavelengths will indeed "penetrate" the leaf biological material itself not just "empty spaces" , that is correct.

SDS pointed this out a while ago and is one reason why green light will drive photosynthesis lower in the canopy...because the red and blue wavelenghts mostly seem to be absorbed by the top parts of the canopy....
Click to expand...
do you have that link handy im having a hard time understanding if it can pass through the upper canopy then why not through the lower? i can see it get reflected but not transmitted
 
KarmaPaymentPlan said:
do you have that link handy im having a hard time understanding if it can pass through the upper canopy then why not through the lower? i can see it get reflected but not transmitted
Click to expand...
Abiqua said:
certain wavelengths will indeed "penetrate" the leaf biological material itself not just "empty spaces" , that is correct.

SDS pointed this out a while ago and is one reason why green light will drive photosynthesis lower in the canopy...because the red and blue wavelenghts mostly seem to be absorbed by the top parts of the canopy....
Click to expand...
MeGaKiLlErMaN said:
Checked it out and just as I thought it isnt really a thing... If you have a tight canopy (scrog or just a trellis) you wont have any light over 100PPF going through the first layer of leaves making this for all intents and purposes a pointless thing to bring up. The numbers were the same for HPS, DE HPS, and COBS.

The only way to get more into the canopy is side lighting and not having a hot spot (IE multiple LES) Which might be a good idea.

Now if you have a stretchy strain then the more PPF/D you have the farther down the light will go, but that doesn't necessarily correlate to more wattage. That "penetration" only exists because there is space for light to pass through (those stretchy strains), but with a proper canopy thats pointless anyways.

Long story short, More PPF/D in a area (to a certain level) is what makes penetration a thing. its not directly dictated by power or how many watts you're pushing, but rather the usable light that is being pushed on the canopy level.
Click to expand...

Not really, Check it out yourself all it takes is a par meter.
 
Cool, so with this wealth of new information my updated project light spec's. If this doesn't look right feel free to chirp in

2x HLG 320H-c1050's (305 forward volts)
16x CXB 3590 3500k
4x 36"x 5.888" Heatsinks (unless you convince me to drop on the sexy pin ones)

640w Output
380ish Par/w
20ish PARw/Sqft.

I would love to run the 700ma drivers but 24 cobs in a 4x4 seems extreme to pattern nicely.

I can't locate that nifty calculator you were using
 
Nugtorrent said:
Damn dude that is legit. Which driver are you using for your second example? I have some notes on the Mean Well 185h-c1050 that I took off growmau5's videos, & he was saying at 179v forward voltage it could power 5 CXB3590's, and the HLG 240hc1050b could power 6. Seems I would be short running 3x 185h-c1050's by a single cob?

Your post is awesome by the way thanks.
Click to expand...

Yeah man you can use w x 185-1050 and 1 x 240-1050 to get to your 16 cobs.5 cobs per on the 185 and 6 cobs on the 240.
 
I realized after the fact that I could also run 16x @ 1050ma using 2x HLG 320H-c1050's @ 305 forward volts. Pretty set on this build, great mix of efficiency power & canopy coverage.
 
Malocan measured the spectral distribution of light that had passed through leaves. Lots of FR in there.

I did see lots of light penetration from the COBs . They can get under the leaves much easier than with higher hanging light sources. I could literally see beams of light passing under the leaves when before there wasn't
 
thanks for the education.. Abiqua..re penetration..i meant that the leaf gets in the way..and a clear path it doesn't it was about direction of light..
 
wietefras said:
Malocan measured the spectral distribution of light that had passed through leaves. Lots of FR in there.

I did see lots of light penetration from the COBs . They can get under the leaves much easier than with higher hanging light sources. I could literally see beams of light passing under the leaves when before there wasn't
Click to expand...

What were the measurements you got? I didnt see anything worth of note coming through at 1200ppfd
 
You must log in or register to reply here.
Back
Top