LED COB bar project

churchhaze

Well-Known Member
I did a few times...still not following. Other than taking things to the extreme ends to show a point.
What am I missing that you're trying to show?\

EDIT:
And of course you edit before I can respond
Are you kidding? It's these extreme ends that make the point. The idea that only PPF matters, and not watts totally misses the point. In order for you to give up watts for PPF, it implies changing the SPD! What that means is you need all the information to put together the whole story. One piece of information doesn't tell you the whole story.

Edit: but when you do know SPD, and it's held constant, then PAR W and PPF tell you the same thing. the idea that you could tweak/optimize for PPF is absurd because doing so without raising efficiency would require changing the SPD.
 
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Greengenes707

Well-Known Member
Are you kidding? it's these extreme ends that make the point. The idea that only PPF matters, and not watts totally misses the point. In order for you to give up watts for PPF, it implies changing the SPD! What that means is you need all the information to put together the whole story. One piece of information doesn't tell you the whole story.
You taking it to another extreme again...who said only PPF matters.
 

churchhaze

Well-Known Member
You taking it to another extreme again...who said only PPF matters.
Nobody said that "only ppf matters", but alesh said that it's more important to know than PAR W. I was responding to alesh.

Edit: the reason i point out the extreme cases is because it sounds like people are reasoning for free lunch. You can have a high PPF of 699nm photons, but making them the correct spectrum would theoretically take additional power. Therefore you can conclude that plants care about power AND quanta.

Edit: If this was not the case, plants would not require any blue at all. Clearly they require some of the photons to be higher energy than others (lower wavelength than others).
 
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Greengenes707

Well-Known Member
It is more important...just the way it is. It is the most directly correlated variable to photosynthesis. Which can be quantified based on photons not energy. It is more relevant shall we call it. If I could only know one figure...PPF all day.
Everyone should want to know in what spectrums their light are coming in(spd). But if you are looking at 2 lamps of a decently educated company/person...PPF is what you want to know.
Of course with the same lamps/spd it doesn't matter...we can even use lumens in that case. but that was not said. 90% of people in here are in the WHITE camp, so again a reductio ad absurdum imo and all I was saying.

Anyways...I digress
 

churchhaze

Well-Known Member
It is more important...just the way it is. It is the most directly variable to photosynthesis. Which can be quantified based on photons not energy. It is more relevant shall we call it. If I could only know one figure...PPF all day.
Everyone should want to know in what spectrums their light are coming in(spd). But if you are looking at 2 lamps of a decently educated company/person...PPF is what you want to know.
Of course with the same lamps/spd it doesn't matter...we can even use lumens in that case. but that was not said. 90% of people in here are in the WHITE camp, so again a reductio ad absurdum imo and all I was saying.

Anyways...I digress
So why do you need 15-20% blue? Why can't you just use extra PPF? It's because of what I'm saying.. You're calling it reductio ad absurdum, but I think you don't get it. The necessity of those 15-20% blue photons means that the PPF must be backed with a certain amount of power. (no more and no less) Without that backing power, those photons could not be blue.
 

Greengenes707

Well-Known Member
So why do you need 15-20% blue? Why can't you just use extra PPF? It's because of what I'm saying.. You're calling it reductio ad absurdum, but I think you don't get it. The necessity of those 15-20% blue photons means that the PPF must be backed with a certain amount of power. (no more and no less) Without that backing power, those photons could not be blue.
Ya...but when I buy(or make) a lamp...it comes in a spectrum. If you want blue you get blue. Not red and try to energize the reds more to shift their spectrum.
Now you're really losing me.

Plants need 15% blue. If it takes you 100w to create 15% of your spectrum blue or it takes you 25w to do it. It's still 15% blue in the end.
 

churchhaze

Well-Known Member
but that was not said. 90% of people in here are in the WHITE camp, so again a reductio ad absurdum imo and all I was saying
It would actually make it moot point, not reductio ad absurdum. In being moot point, the whole "PPF all day" argument is also out the window. It contradicts your own argument.

Edit: In that case, like we both agreed on, watts and PPF tell you literally the same thing for a "white" lamp with similar SPD.
 

Greengenes707

Well-Known Member
It would actually make it moot point, not reductio ad absurdum. In being moot point, the whole "PPF all day" argument is also out the window. It contradicts your own argument.

Edit: In that case, like we both agreed on, watts and PPF tell you literally the same thing for a "white" lamp with similar SPD.
No, for the exact they do.
For similar...the advantage will be shown in PPF.
As well as in the YPF.

I came in here to give my experience of a similar setup to the OP. If you want to continue this...PM me.

Sorry bmdiyh
 
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churchhaze

Well-Known Member
No, for the exact they do.
For similar...the advantage will be shown in PPF.
As well as in the YPF.
Assuming efficiency remains constant:

If PPF increases while SPD stays the same, power must have also increased.

If PPF increases while power stays the same, SPD must have been shifted toward the red.

Edit: There is no free lunch.. you can't simply use less blue to obtain higher PPF.. The amount [of blue] you need is fixed!
 
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guod

Well-Known Member
the only thing that count for a plant are µmols,
independently from the wavelenght (see McCree)
we could grow with a green spectrum if there was not...
the sensor phalanx.
the information from here controls everything, from germination to flower
this is the real pussy for a healthy plant


nrg2049-i1.jpg
 

churchhaze

Well-Known Member
the only thing that count for a plant are µmols,
independently from the wavelenght (see McCree)
we could grow with a green spectrum if there was not...
the sensor phalanx.
the information from here controls everything, from germination to flower
this is the real pussy for a healthy plant


View attachment 3447730
But we do have to cater to those sensors, which means we need some of those umols to have higher energy than others. (or they'd all be the same wavelength) Saying spectrum matters implies power matters, because the only thing that differentiates 2 individual photons is the amount of energy they carry. If you need 10-20% blue, it implies that some of your umols MUST be higher energy than others, and thus umols couldn't possibly be the only thing that counts.

Edit: The light lacking in blue will also be lacking in power, despite not lacking in umol/s.
 
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bmdiyh

Well-Known Member
Guys, great job! Didn't get much, but I hope you resolved it ;)

I am looking at the CXB3590s and I see CB, CD, BB, AD what is the difference. Also in the spreasheets the chips with different letters at the end have different results. Can someone tell me what they mean?
 

alesh

Well-Known Member
Nobody said that "only ppf matters", but alesh said that it's more important to know than PAR W. I was responding to alesh.

Edit: the reason i point out the extreme cases is because it sounds like people are reasoning for free lunch. You can have a high PPF of 699nm photons, but making them the correct spectrum would theoretically take additional power. Therefore you can conclude that plants care about power AND quanta.

Edit: If this was not the case, plants would not require any blue at all. Clearly they require some of the photons to be higher energy than others (lower wavelength than others).
Yes, spot on. It might be even better to compare photon output (µmol/s) than energy output (W) but this is good enough.
I think that photons are always at least as accurate as watts, and even more in most cases. I really don't get your point. A lamp might not work well if it doesn't have enough blue. But the lack of blue isn't caused by the choice of measure.
Had I been choosing a LED I'd have dismissed all the LEDs with unsatisfying SPD (such as the lack of blue) and then choose the one with the highest photon output. That's what I meant.

And yes, for whites, these two measures are almost interchangeable.
 

bmdiyh

Well-Known Member
When I decided on which driver to go with I contacted a supplier to ask for a price for a certain number of drivers. I got a reply asking me for clarification on the type of driver I want:

"...
As you requested for Meanwell HLG-185H-C1400, following is brief information:
1. Constant current design.
2. Input:90 ~ 305VAC 127VDC ~ 431VDC
3. Output: 71-143V, 1400mA
5. Warantty: 5 years

There are four types for option:
Blank: IP67 rated. Cable for I/O connection.
A: IP65 rated. Output voltage and constant current level can be adjusted through internal potentiometer.
B: IP67 rated. Constant current level adjustable through output cable with 1~10V dc or 10V PWM signal or resistance.
D (option): IP67 rated. Timer dimming function, contact MEAN WELL for details."

Can someone clear that out for me? What is the difference between all of those, and what exactly will I need? Do I even need a dimmer?
 

salmonetin

Well-Known Member
....i saw info about D option...

http://users.tpg.com.au/users/p8king/files/hlgd.pdf

pd... a option no dimm external... or no dimm
b option if you go on dimm with external pot....
......normally the peolpe go on a or b version
d option ....its the first time i saw...

pd1...in the pdf...
by directly replacing the 3 in 1 dimming PCB with the timer
dimming control board (pcb).

...they sell a customizable timer dimming control board (pcb) apart?.... ...im dreaming again...:bigjoint:

saludos
 
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bmdiyh

Well-Known Member
"3. Output: 71-143V, 1400mA"

Does this mean I have to get the
CREE CXB3590 3500K CD at 72v?

And can someone tell me what are CB, CD, DB, DD? I found out that it's "bin", but what does it mean?
 

testiclees

Well-Known Member
"3. Output: 71-143V, 1400mA"

Does this mean I have to get the
CREE CXB3590 3500K CD at 72v?

And can someone tell me what are CB, CD, DB, DD? I found out that it's "bin", but what does it mean?
Bin refers to the performance quality class of the cob. You can review the data sheets for each product and the specs for various bins are given.

CD is the killah in that instance. But unavailable as far as i can see.

If you track down any of the cxb 3590 cd bin, 3500k, 72v. PLEASE LET ME KNOW YOUR SOURCE.
 

bmdiyh

Well-Known Member
Bin refers to the performance quality class of the cob. You can review the data sheets for each product and the specs for various bins are given.

CD is the killah in that instance. But unavailable as far as i can see.

If you track down any of the cxb 3590 cd bin, 3500k, 72v. PLEASE LET ME KNOW YOUR SOURCE.
I have actually tracked down a source. It's Chinese suppliers from Alibaba.com I am in contact with him right now, talking over shipment prices and availability of products.
 

testiclees

Well-Known Member
I have actually tracked down a source. It's Chinese suppliers from Alibaba.com I am in contact with him right now, talking over shipment prices and availability of products.
please keep me posted.

also be sure to confirm/ verify that you have all the details correct.

I was not successful finding that particular cob on ali. Which supplier are you referring to please?
 
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