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efficiencyHello guys, RUI is a wonderfull place.
But after spending a lot of time on this forum there are many things i still don't get :
When i c ompare CXB3070 bin AB, and CXB3590 bin CB using the Cree tool, i get those numbers
When i check the thread "COB efficiency spreadsheet" i get different ones
- CXB3070AB : examples @0.7A, 170 lm/w vs 157, @1.4A 147 lm/w vs 137.7

- CXB3590CB : @0.7A 167.9 lm/W vs 150 lm/w, @1.4A 128.5 lm/w vs 119.8


I don't know why ?

Now, if i want to try to make my own data sheet based on the Cree tool, i'm not sure how to procede.

I will try correct me if i'm wrong :

1) Efficiency (%) = (lm/w) / LER, i think at 3000K LER is 325 for both LED so :
CXB3070AB 3000K :
@0.7A efficiency = (157.2 / 325) = 48.4%
@1.4A efficiency = (137.2 / 325) = 42.4%

CXB3590CB 3000K :
@0.7A efficiency = (150.5 / 325) = 46.3%
@1.4A efficiency = (119.8 / 325) = 36.9%

2) PARwatts = efficiency x dissipated watts (with dissipated watts = Amps*Volts)
CXB3070AB 3000K :
@0.7A PARwatts = 48.4 x 23.35 = 11.29 (Which unit is it ?)
@1.4A PARwatts = 42.4 x 49.315 = 20.89

CXB3590CB 3000K 72V:
@0.7A PARwatts = 46.3 x 48.276 = 22.36
@1.4A PARwatts = 36.9 x 103.306 = 38.08

And now i'm in troubles because i would like to go deeper and find PPF but i'm not sure how to do that ! I think it's somthging like that :
3) PPF = PARwatts x convertion factor... What is "convertion factor"? is it QER ? which is the value of that factor ? Same question for QER ?
Based on my research on RIU i think, but i'm not sure QER = 4.66 for Cree CXs 3000K 80CRI.
I will try this formula with convertion factor = QER = 4.66 but it's highly speculitive if not absolutely wrong!

so :
CXB3070AB 3000K :
@0.7A PPF = 11.29 x 4.66 = 52.61 μmol / s
@1.4A PPF = 20.89 x 4.66 = 102.36 μmol / s

CXB3590CB 3000K 72V :
@0.7A PPF = 22.36 x 4.66 = 104.2 μmol / s
@1.4A PPF = 38.08 x 4.66 = 177,45 μmol / s

4) PPFD : now i would like μmol / s / m² Obviously i don't know how to do that !
but idealy i have 2 goals :
a) evaluate the best surface of grow (i don't care that much about vegging, i plan to make a SOG)
b) evaluate the closest distance i can put my leds from the canopy. actualy i don't have any led, i'm just calculating what is my best option : i have space on the ground ( 2 or 3m²), but i don't have much heigh, it's my main problem, only 4 feets (1.2m) and i don't have any better option.
Question what is a good PPFD (i think it's between 800 - 1500 μmol / s / m²,) what is the closest distance, the best set-up etc.

It's a lot of questions, and a long post, if anyone can read that and help me i would appreciate a lot.
Thank you RIU fellows !

LMAO, Yep that just happened. I saw the first chart and tinkled a little.

The Punisher said:

efficiencyHello guys, RUI is a wonderfull place.
But after spending a lot of time on this forum there are many things i still don't get :
When i c ompare CXB3070 bin AB, and CXB3590 bin CB using the Cree tool, i get those numbersView attachment 3515386
When i check the thread "COB efficiency spreadsheet" i get different ones
- CXB3070AB : examples @0.7A, 170 lm/w vs 157, @1.4A 147 lm/w vs 137.7
View attachment 3515395
- CXB3590CB : @0.7A 167.9 lm/W vs 150 lm/w, @1.4A 128.5 lm/w vs 119.8
View attachment 3515406

I don't know why ?

Now, if i want to try to make my own data sheet based on the Cree tool, i'm not sure how to procede.

I will try correct me if i'm wrong :

1) Efficiency (%) = (lm/w) / LER, i think at 3000K LER is 325 for both LED so :
CXB3070AB 3000K :
@0.7A efficiency = (157.2 / 325) = 48.4%
@1.4A efficiency = (137.2 / 325) = 42.4%

CXB3590CB 3000K :
@0.7A efficiency = (150.5 / 325) = 46.3%
@1.4A efficiency = (119.8 / 325) = 36.9%

2) PARwatts = efficiency x dissipated watts (with dissipated watts = Amps*Volts)
CXB3070AB 3000K :
@0.7A PARwatts = 48.4 x 23.35 = 11.29 (Which unit is it ?)
@1.4A PARwatts = 42.4 x 49.315 = 20.89

CXB3590CB 3000K 72V:
@0.7A PARwatts = 46.3 x 48.276 = 22.36
@1.4A PARwatts = 36.9 x 103.306 = 38.08

And now i'm in troubles because i would like to go deeper and find PPF but i'm not sure how to do that ! I think it's somthging like that :
3) PPF = PARwatts x convertion factor... What is "convertion factor"? is it QER ? which is the value of that factor ? Same question for QER ?
Based on my research on RIU i think, but i'm not sure QER = 4.66 for Cree CXs 3000K 80CRI.
I will try this formula with convertion factor = QER = 4.66 but it's highly speculitive if not absolutely wrong!

so :
CXB3070AB 3000K :
@0.7A PPF = 11.29 x 4.66 = 52.61 μmol / s
@1.4A PPF = 20.89 x 4.66 = 102.36 μmol / s

CXB3590CB 3000K 72V :
@0.7A PPF = 22.36 x 4.66 = 104.2 μmol / s
@1.4A PPF = 38.08 x 4.66 = 177,45 μmol / s

4) PPFD : now i would like μmol / s / m² Obviously i don't know how to do that !
but idealy i have 2 goals :
a) evaluate the best surface of grow (i don't care that much about vegging, i plan to make a SOG)
b) evaluate the closest distance i can put my leds from the canopy. actualy i don't have any led, i'm just calculating what is my best option : i have space on the ground ( 2 or 3m²), but i don't have much heigh, it's my main problem, only 4 feets (1.2m) and i don't have any better option.
Question what is a good PPFD (i think it's between 800 - 1500 μmol / s / m²,) what is the closest distance, the best set-up etc.

It's a lot of questions, and a long post, if anyone can read that and help me i would appreciate a lot.
Thank you RIU fellows !

Click to expand...

Your 1-4 questions are fine. #4 for PPFD: is just PPF÷area(m2).


As for the cree tool...it's actually showing performance based on Tj and not necessarily the Tc like supra and others charts are based off...and even when Tsp is selected in the tool, it's still showing Tj. It's because when the measurements/charts were made they were from pulsed light in preset ambients, thus Tc would equal Tj. But once in steady state operation, Tc and Tj separate by about 30*. An example would be a 55c case temp(Tc) is actually 85c junction temp(Tj). So to see the numbers from supras charts, you need to put in 20c for Tj.

Post#30
https://www.rollitup.org/t/ppfd-what-sort-of-performance-for-this-setup-and-space.877135/page-2#post-11767933

Hello everybody. I'm interested in building my own cob light and am not sure on some details. I want to use vero29 4000k. I want my light to be for both veg. and flower for a 3x4 space. I was thinking either 3 or 4 vero29 would be enough, based on some of the info I've read on these forums. I like the arctic alpine 11 pro rev .2 cpu cooler for each cob. And for the driver, I'd like to run each cob with its own. I think a meanwell LPF 90-40 would work??? As you can tell, there are considerable gaps in my knowledge on cobs. I don't know which cob to buy, there all kinds of options for vero29 on digikey.com. Can anyone please help fill in the gaps for me? I am new to growing and want to make a quality light that I can use for a long time. Thanks for any responses.

Greengenes707 said:

Your 1-4 questions are fine. #4 for PPFD: is just PPF÷area(m2).


As for the cree tool...it's actually showing performance based on Tj and not necessarily the Tc like supra and others charts are based off...and even when Tsp is selected in the tool, it's still showing Tj. It's because when the measurements/charts were made they were from pulsed light in preset ambients, thus Tc would equal Tj. But once in steady state operation, Tc and Tj separate by about 30*. An example would be a 55c case temp(Tc) is actually 85c junction temp(Tj). So to see the numbers from supras charts, you need to put in 20c for Tj.

Post#30
https://www.rollitup.org/t/ppfd-what-sort-of-performance-for-this-setup-and-space.877135/page-2#post-11767933

Click to expand...

Plus Supra uses typical (halfway to the next bin) luminous flux values.

Well with help from many here I have put together my new LED bloom light, replacing my MARS 2 1200. I just posted some pics in the showoff thread here. I was trying to passive cool and the heatsinks are hovering between 74-79 degrees, does this sound good?

Now I would like to work on planning to replace my MARS 2 400 veg light. I was looking at the 5000k CD bin CXB3590's. Exactly how many target watts per square foot am I looking at? I would say the biggest my girls get is 4'x4' during veg time but I might want something that can cover 5'x5'. Thanks all!

http://howtogrowmarijuana.com/led-grow-lights/ Not sure if this has been posted, but here's a review of quite a few commercial lights. Tells you what LEDS, ect. that they use in each one. Just click on one to see them all

hey guys...not to annoy everyone, but im posting twice to two different threads, so if ever you have encountered this please bare with me, but im actually either suggesting or looking for advice. ive tried outdoors and indoors using metal halides and led's. just came across with my salt water reef aquarium ive been using LED's with very advance controllers. please check this link below: what im currently using on my reef tank http://www.marinedepot.com/AquaIllumination_Hydra_TwentySix_LED_Fixture_20_Inch_LED_Light_Fixtures-AI_(AquaIllumination)-3Z4811-FILTFILDTN-vi.html ) other products that im checking http://www.advancedaquarist.com/2013/8/review ) since the LED's on reef tanks are cheaper and more convenient to use, the same reason also that corals/reefs need better lighting than land plants. im gettin good healthy corals. thanks

Budsmkr08 said:

Hello everybody. I'm interested in building my own cob light and am not sure on some details. I want to use vero29 4000k. I want my light to be for both veg. and flower for a 3x4 space. I was thinking either 3 or 4 vero29 would be enough, based on some of the info I've read on these forums. I like the arctic alpine 11 pro rev .2 cpu cooler for each cob. And for the driver, I'd like to run each cob with its own. I think a meanwell LPF 90-40 would work??? As you can tell, there are considerable gaps in my knowledge on cobs. I don't know which cob to buy, there all kinds of options for vero29 on digikey.com. Can anyone please help fill in the gaps for me? I am new to growing and want to make a quality light that I can use for a long time. Thanks for any responses.

Click to expand...

Bonjour
You have a 3x4...so 12sq/ft...30w per sq/ft for bloom...12x30=360W
So if you look for efficiency you gonna need 360w...400w would be great
2 hlg-185-1050 and 10xV29!
Or better but more expensive...8 cxb 3590 3500ºk 36V CD on 2 hlg-185-1400b + 2 heatsink+ fans+....750 $ for 400w of the best cob!
Have a great day ★

Hey guys ,would it be possible to veg and flower under 3000 k cxb-3070's or would I need a separate veg light?

bluespicker said:

Hey guys ,would it be possible to veg and flower under 3000 k cxb-3070's or would I need a separate veg light?

Click to expand...

3000K can veg very well.

Thanks alesh,time to start ordering the materials!!

QUOTE="bluespicker, post: 11970232, member: 912587"]Thanks alesh,time to start ordering the materials!![/QUOTE]
Bonjour
Why 3070 and not 3590?
Why 3000ºk and not 3500ºk? Maybe better if you plan to vegg...
Are you going to get a hlg-185-1400b/a?
Have a great day ★

Thanks for the reply little Jacob. I had no idea how to calculate how many watts per ft2, that was obviously a lot more than I was thinking I needed! But thanks for the info on the drivers too!

Hi guys. I posted this elsewhere but need to know. Do you guys get confirmation from someone besides Paypal when you order from Kingbrite? I paid them on the 28th of last month. Not a lot of time but I enquired with Jerry at Kingbrite and he asked me if I saw the bill. Wish me luck. Any confirmations usual?

littlejacob said:

QUOTE="bluespicker, post: 11970232, member: 912587"]Thanks alesh,time to start ordering the materials!!

Click to expand...

Bonjour
Why 3070 and not 3590?
Why 3000ºk and not 3500ºk? Maybe better if you plan to vegg...
Are you going to get a hlg-185-1400b/a?
Have a great day ★[/QUOTE]

This will be my first build for a smaller tent so I plan to go with the 3070 to get the feel of things.
Later I plan to do a 3590 build for my larger tent,and yes I plan to get the hlg-185-1400a.

Bonjour
To practice I bought a few cheap 20w cobs (6 $ each + 2 cheap driver 7 $ and vga cooler x4 10 $...30 $ to practice...)
CU

MrEus1 said:

Hi guys. I posted this elsewhere but need to know. Do you guys get confirmation from someone besides Paypal when you order from Kingbrite? I paid them on the 28th of last month. Not a lot of time but I enquired with Jerry at Kingbrite and he asked me if I saw the bill. Wish me luck. Any confirmations usual?

Click to expand...

F.Y.I. I ended up emailing Jerry a copy of the email receipt from Paypal for my Cobs, power supply and cob holders and after reviewing it, he has decided to complete and ship the order. Nice guy. So 10 or 11 days shot waiting for nothing. So weird. I ordered 4' led tubes for veg. Half got to my house, half didn't. Then I ordered some shop lights to remove the ballasts from and use the leds in and they got lost. Now my cobs! All in the past 30 days and the past 3 online orders from 3 different companies. Just lucky I guess. Kingbrite meanwhile has been sending me emails trying to get me to order more stuff. Well. I have my 4' heat sink and if all goes well, I sure will. 4 cobs per heat sink. Total of 8 heat sinks total. That's the plan. I will let you know if the next order gets me a confirmation so that you might know what to expect. Peace and pot

MrEus1 said:

F.Y.I. I ended up emailing Jerry a copy of the email receipt from Paypal for my Cobs, power supply and cob holders and after reviewing it, he has decided to complete and ship the order. Nice guy. So 10 or 11 days shot waiting for nothing. So weird. I ordered 4' led tubes for veg. Half got to my house, half didn't. Then I ordered some shop lights to remove the ballasts from and use the leds in and they got lost. Now my cobs! All in the past 30 days and the past 3 online orders from 3 different companies. Just lucky I guess. Kingbrite meanwhile has been sending me emails trying to get me to order more stuff. Well. I have my 4' heat sink and if all goes well, I sure will. 4 cobs per heat sink. Total of 8 heat sinks total. That's the plan. I will let you know if the next order gets me a confirmation so that you might know what to expect. Peace and pot

Click to expand...

So Jerry got it shipped and sent me a tracking # . Alright.

MrEus1 said:

So Jerry got it shipped and sent me a tracking # . Alright.

Click to expand...

So,any help will be appreciated. My cobs are supposed to be delivered today. Pretty exciting. So what gage wire are you guys typically using? I'm thinking what, 12 or 14 gage. I'm going to be running 4 3590"s with a Mean Well HGL-185H C1400B driver. Does my memory fail? It's been a very long while since I did an electronics project. I think the last time, I built a voltage meter from a kit. Anyway, oh and I've seen 99% pure silver compound for mounting the cobs or other hot electronics to a heat sink. Sounds good to me. What do you guys think? I'm sure that I'll have more to inquire about and or share as this build takes it's course. I plan on repeating it at least 7 more times so with any luck we might learn something together. And like I said, any guidance will be appreciated. So again, wire gage? 99% pure silver mounting paste? Sure. it's expensive in comparison I suppose but still only six dollars and change for a tube. I dunno the size and it really doesn't matter until I run out, right?