COB question

FranJan said:

"When you are seeking Efficiency, larger chips will always trump mutable smaller ones"
Hey Pico can you explain this a bit more. This article illustrates what I've been led to believe about LED efficiency.

http://www.myhydroponicgardening.com/the-cannabis-growers-guide-to-led-grow-lights-1w-versus-3w-and-higher/

"To be more clear: a 3W LED is not 3x as bright, powerful, or intense as a 1W LED. Expanding upon this, we can reach the conclusion that three individual 1W LEDs will be brighter, more powerful, and more intense than a single 3W LED and the reason comes down to efficiency."

Click to expand...

So lets look at whats inside a COB light, I would like you to have a look at the video I made of the Bridglelux Chip:

[video=youtube;i4g1biKEYBw]http://www.youtube.com/watch?v=i4g1biKEYBw[/video]

I will explain to you a few of the concepts of operation I have formulated in my own mind. Firstly the article you linked me to is interesting and does raise a few good points, like the 3 watt chips used in the panels where way under efficient compared to 1 watters. There are two sides to this story, the first being, these chips suck but this is only looking at the bloggers facts at face value tho, I have looked myself into a lot of panel designs and one of the common practices manufactures will do, is run high watt chips well under the rated power. Now from their point of view, you could advertise a system with 30 x 3 watt diodes but never actually say its a 90 watt panel. You could then, some what hiding the fact that you are doing this by using a shitty PSU and connecting fans to the circuit bringing your over all power usage up to about the 90 watt mark.

I don't know what panel this guy tested on how but I know there are very good diodes available in a wide range of wattage's from less then one watt up to 10 even 20 watts. Poor design and questionable marking tactics has given a bad name to LED grow panels in general. I can assure you there are 3 watt chips that would be equal or better then to 3 x 1 watters.

The COB design really his a massive step into upping the power and control over LED light. I don't if you used to follow computer chip manufacturing back in the day, early 2000's but this is a lot like what is going on with these new LED chips. As they make diodes bigger and bigger things start to get out of hand with regard to current flow and utilizing different materials, things really would start to get out of control trying to push 10 amps through a single diode. COB are a master peace of power distribution on the micro level, they are using technology similar to computer chip dies, different packaging technics is allowing for higher heat dissipation, better bonding, higher temperatures and ultimatum high efficiency.

In the video you can see every stage of the chips illumination, we start by seeing the parallel diode banks energizing, when one bank is saturated it consumes the voltage drop and you have another bank energize. Power increases and then you final have a uniform voltage across the die, the chip works in the lossy state for quite a large in-cress in voltage, the diodes at this power are only working with them self's, the light as many point sources as there are diodes at this stage. When you get to the upper end of this state, this is where you see the diodes excite the color coating, the light starts to sharpen off almost, things are starting to increase in temperature around the diodes, this is the power level in which the diode start to couple with the plastic (I think it may be some sort of phosphor coating?). At this point the uniform coating and each individual LED is coupled to each other acting as one, your only limits will now be the failure temperature of the diodes or coating. Efficacy wise, think about hundreds of people pulling one load up a hill, as apposed to each person caring a portion of it individually, the individuals are highly effected by small changes in the environment, but using a single load and letting everyone work together gives the load much more momentum.

No one has to think what I say is correct, I could be very well talking out of my ass but always what I try to imagine is how to relate things you can observe into your everyday life concepts. I know in my head I understand this but weather this all can make scene in your head is another thing, I hope its helpful,

Lastly, SDS and me will have our day, I just know it ;D

There are two sides to this story, the first being, these chips suck but this is only looking at the bloggers facts at face value tho, I have looked myself into a lot of panel designs and one of the common practices manufactures will do, is run high watt chips well under the rated power. Now from their point of view, you could advertise a system with 30 x 3 watt diodes but never actually say its a 90 watt panel

Click to expand...

I didnt like that Point in that article, because we know they r just sold as 3W but what they r driven at is what matters. But regarding Efficiency i would make another analogy. Its like driving a car at higher Speeds, the car gets faster but the Petrol consumption doesnt increase in linearity but actually gets higher as it should for the given Speed, so driving faster at a certain point is more unefficient. Or as in biology where if a round Body gets bigger the volume increases in third potency while surface increases in 2nd, so smaller bodies dissipate more heat faster thats why little birds have to eat all day and r like hyperactive. Lol wrong topic. But its the same with those leds, u put more power in but light Output is less than what you should get in for the power put it. But as for those COBs it might be a different Thing, idk i will look into this. With these consisting of all those Little Chips like put together in a big Cluster might be a different Thing and those analogies dont work if they e.g. consist like of like 100 mini dies put together. ,

I am aware that his first language is not English and you yourself might connect with what he is saying

Click to expand...

lol no, sometimes its really hard to understand a Thing. Doing a Little math:

do an example, lets say you are averaging 1 amp of current at 10 volts to get 1000 lumens which will give you a certain amount of growth

Click to expand...

for 1 meter! of copper cable 1,5mm^c @ 1 A the Voltage loss would be like 0,12V so for my Little DIY Panel it would be so small i could not measure it with the tolerance of my DMM.

I use the two LEDs above and rely on the reflections to diffuse the light at almost every angle around the plant, to achieve very high ambient light levels, saturating everything in light just like outside.

Click to expand...

reflection = significant amount of light loss, no? I mean we just talked about Efficiency and stuff...

I have observed some unique leaf movement that I am not sure, if its connect to this style or type of lighting or just something I don't understand about the plants yet.

Click to expand...

interesting, like what? When i first came to RIU i found this Topic: https://www.rollitup.org/led-other-lighting/658111-what-kind-light-mj-likes-2.html SDS provides quite some datasheets and stuff. So i oriented my self on those values given there:

Clones / Seedlings

Blue Range 400-499nm .Peaks pref. @ ~ 410 nm , ~430 nm & ~453 nm : 20-25%
Green Range 500-550 nm .Peaks pref. @ ~ 550 nm : 20-25 %
Yellow-Amber Range 551-599 nm .Peaks pref. @ ~ 599 nm : 5-10%
Red Range 600-639 nm .Peaks pref. @ ~ 625 nm : 15-20%
Deep Red Range 640-670 nm .Peaks pref. @ ~642 nm & 662 nm : 5-10 %
Far Red Range 671-750 nm .Peaks pref. @ ~680 nm ,700 nm & ~730 nmm : 5-10 %


Young Plants

Blue Range 400-499nm .Peaks pref. @ ~ 410 nm , ~430 nm & ~453 nm : 10-15%
Green Range 500-550 nm .Peaks pref. @ ~ 550 nm : 10-20 %
Yellow-Amber Range 551-599 nm .Peaks pref. @ ~ 599 nm : 25-30%
Red Range 600-639 nm .Peaks pref. @ ~ 625 nm : 30-40%
Deep Red Range 640-670 nm .Peaks pref. @ ~642 nm & 662 nm : 10-15 %
Far Red Range 671-750 nm .Peaks pref. @ ~680 nm ,700 nm & ~730 nmm : 3-5%



Early Flowering

Blue Range 400-499nm .Peaks pref. @ ~ 410 nm , ~430 nm & ~453 nm : 8-10 %
Green Range 500-550 nm .Peaks pref. @ ~ 550 nm : 10-20 %
Yellow-Amber Range 551-599 nm .Peaks pref. @ ~ 599 nm : 10-20%
Red Range 600-639 nm .Peaks pref. @ ~ 625 nm : 25-30 %
Deep Red Range 640-670 nm .Peaks pref. @ ~642 nm & 662 nm : 25-35 %
Far Red Range 671-750 nm .Peaks pref. @ ~680 nm ,700 nm & ~730 nmm : 3-5%


Middle Flowering

Blue Range 400-499nm .Peaks pref. @ ~ 410 nm , ~430 nm & ~453 nm : 8-10 %
Green Range 500-550 nm .Peaks pref. @ ~ 550 nm : 1-15 %
Yellow-Amber Range 551-599 nm .Peaks pref. @ ~ 599 nm : 5-10%
Red Range 600-639 nm .Peaks pref. @ ~ 625 nm : 25-30 %
Deep Red Range 640-670 nm .Peaks pref. @ ~642 nm & 662 nm : 30-55 %
Far Red Range 671-750 nm .Peaks pref. @ ~680 nm ,700 nm & ~730 nmm : 3-5%


Late Flowering

Blue Range 400-499nm .Peaks pref. @ ~ 410 nm , ~430 nm & ~453 nm : 1-8 %
Green Range 500-550 nm .Peaks pref. @ ~ 550 nm : 1-10 %
Yellow-Amber Range 551-599 nm .Peaks pref. @ ~ 599 nm : 1-10%
Red Range 600-639 nm .Peaks pref. @ ~ 625 nm : 25-40 %
Deep Red Range 640-670 nm .Peaks pref. @ ~642 nm & 662 nm : 35-70 %
Far Red Range 671-750 nm .Peaks pref. @ ~680 nm ,700 nm & ~730 nmm : 3-5%

Click to expand...

Do you think they r good or crap or dont know? Sorry for those strange capital letters in my text, its not me but the language Setting in my browers is altering my writing.

Lax, I think some of the main points I want you to take away from this discussion is to do I lot of your own thinking, I am not going to say Stardust is wrong straight away or not, people often reveal that them self given time. I know the electrical losses I am taking about are small, but always keep them in mind, you have to understand losses between interconnects are always there, and understanding them will only help you build better panels, say when you solder wires together, also clean the bare ends with alcohol for less contamination, stuff like that.

The reflection issue is a big one, but I don't see how else I can replicate that high ambient light I wanted unless doing want I talked about with hundreds of light point sources around the plant, and even then would not be as even. reflector losses are high but that light would be going to waste anyway if there was nothing.


Here is the leaf opservation from my thread:

It is a battle right now with trying to give them just the right amount of water. So I noticed that the leaves can droop two ways, they used to drop like that the leave itself would be curved from the start, where it connects and curve so the tips are pointed down, now the drooping is different. They leves will stay straight and rigid but bend from the stem curving it downward. I have been giving them micro sleeps sometimes during the day and after about 15 min the main stem leaves or I guess fan leaves are bent down looking like they are some how protecting the stem and undergrowth, after the lights come back on for a few hours they straighten back out. I don't know if this a natural thing like during the night it some how helps the plant or a water issue I can't dial in yet??

Click to expand...

In my opinion what stardust is doing, is like making some sort of overly complex fuel for the plants rather then just giving it as much as it needs, its like mixing in all there special chemicals into you cars gasoline and limiting the flow to micro drops and trying to measure the tiny little increases in horsepower from the engine, don't you think giving the plant as much as it needs and letting it decide what do do with it is best, after all they are more intelligent then us right

I know the electrical losses I am taking about are small, but always keep them in mind

Click to expand...

trying to do my own thinking id say if loss by interconnect is so low in my case my DMM would not be able to detect it or its within its tolerance id say benefit for coverage> interconnect loss

don't you think giving the plant as much as it needs and letting it decide what do do with it is best

Click to expand...

isnt that the main riddle for Efficiency and so on. Giving it the exact amount it Needs. You can have the most effcient Chips, but if u over saturate with light its for nothing and even might cause damage. Also, i mean yeast will produce alcohol in anaerobic conditions in such amounts that it will die from alcohol toxcicity if not diluted, not very clever imo, i made some small experiments with some fast growing herbs and tomato in led vs sunlight. I used massive %amounts of 660 and observed a massive root growth compared to sunlight growth. Reading here its like "oh noes just use them 660 in flower" I would love to but i dont have the capacity to test funny stuff like that as i have not one complete mj grow on my list lol, so i wont do my own testing and thinking there and just go with what the "majority" says. What im trying to say i think there is potential letting humans decide what is best and not the plants. Similar to genetic Engineering, "unnatural" but effective -understanding and exploiting.

Just because a COB/multichip is 10W doesn't mean it's a single 10W chip. To say larger chips are less efficient because a 3W isn't as efficient as a 1W, therefore COB's aren't as efficient as 1W LED's, is flawed logic upon flawed logic if you ask me. A lot of COB's use 1W chips anyway, and to my knowledge 3W chips are usually less efficient than 1W because of the driving current and LED "droop." As we perfect growing crystals LED's should suffer less and less from larger chips, higher driving currents, and higher junction temps.

lax123: I agree with those SPD break downs.

[

But as for those COBs it might be a different Thing, idk i will look into this. With these consisting of all those Little Chips like put together in a big Cluster might be a different Thing and those analogies dont work if they e.g. consist like of like 100 mini dies put together. ,

Click to expand...

thx spheda, so i thought right there i guess. lol a lot of words could have been saved but practicing english is always good

Hey whats up?
I was looking into that cob stuff and want some, lol.
I dont wanna advertise if its shit, but i cant Keep this from you.
I looked on ebay and found this crazy seller "sure-display" they have some sort of sellout/Special offer stuff...
e.g. 100W cob for WTF 8,50$ http://www.ebay.com/itm/100W-Warm-White-High-Power-LED-Panel-9000LM-100-Watt-Lamp-Light-/380515680644?pt=LH_DefaultDomain_0&hash=item5898808184
100W is too "hot" for me, litererally, so i ordered some 30W 630nm cobs and 30W WW (for like 3,50$ per PCs rofl) and 30W Drivers for like 4$...
as i said cant Keep that from you That special offer stuff ends like in 2 days.

In other words you could build like a 1000W Panel for less then 200$ + heatsink or something lol.
-Downside 100 bad Reviews on that seller (mostly shit taking to Long from China) on the other Hand +27k items sold, so i think its legit.

What do you think?

lax123 said:

Hey whats up?
I was looking into that cob stuff and want some, lol.
I dont wanna advertise if its shit, but i cant Keep this from you.
I looked on ebay and found this crazy seller "sure-display" they have some sort of sellout/Special offer stuff...
e.g. 100W cob for WTF 8,50$ http://www.ebay.com/itm/100W-Warm-White-High-Power-LED-Panel-9000LM-100-Watt-Lamp-Light-/380515680644?pt=LH_DefaultDomain_0&hash=item5898808184
100W is too "hot" for me, litererally, so i ordered some 30W 630nm cobs and 30W WW (for like 3,50$ per PCs rofl) and 30W Drivers for like 4$...
as i said cant Keep that from you That special offer stuff ends like in 2 days.

In other words you could build like a 1000W Panel for less then 200$ + heatsink or something lol.
-Downside 100 bad Reviews on that seller (mostly shit taking to Long from China) on the other Hand +27k items sold, so i think its legit.

What do you think?

Click to expand...

I think you would have to be a fool to buy such shit from eBay.

Why do you think thats shit? I mean i could pay 8x the Price to buy the same made in China stuff in my Country. 27k+ items sold, if its so shitty i would like expect 6k+ buyers writing negative item is defective or something. I mean for the cost of a "brand" Panel you could get 2000W in quite efficient cob. Im always like checking Google and Forums for items like that to find negative comments and so on (usually Aqua Forums buy a lot of led stuff)...found nothing that would stop me from buying

lax123 said:

Why do you think thats shit? I mean i could pay 8x the Price to buy the same made in China stuff in my Country. 27k+ items sold, if its so shitty i would like expect 6k+ buyers writing negative item is defective or something. I mean for the cost of a "brand" Panel you could get 2000W in quite efficient cob. Im always like checking Google and Forums for items like that to find negative comments and so on (usually Aqua Forums buy a lot of led stuff)...found nothing that would stop me from buying

Click to expand...

Even if they do come out of the same factory as a Sharp or Cree COBs, quality control and propriety manufacturing processes and bonding techniques would surely not be the same. The big company's spend a lot of money figuring this stuff out. I would have thought if you are going to hand build something nice, you would have gotten better chips, even if the seller offers to replace blown chips I would not want to deal with all the hassle with changing them if they do. Stick with what you know and with me I never buy new stuff off eBay, only used, I thought that's what it was for anyway...

hmm yea you r right. i guess it depends on expectation. if id buy 1000W for just 85$ id say fuck it if one or two r defective compared too 1 or 2 "Quality" cobs for the same Price. yea Efficiency is lower, but then id still have like 700W "for free". I mean 1000W for 85$ those r some seriously crazy numbers imo

PICOGRAV said:

Even if they do come out of the same factory as a Sharp or Cree COBs, quality control and propriety manufacturing processes and bonding techniques would surely not be the same. The big company's spend a lot of money figuring this stuff out. I would have thought if you are going to hand build something nice, you would have gotten better chips, even if the seller offers to replace blown chips I would not want to deal with all the hassle with changing them if they do. Stick with what you know and with me I never buy new stuff off eBay, only used, I thought that's what it was for anyway...

Click to expand...

I think people would like to think, that the nicer LED's they shelled out for are really the bee-knee's, but that doesn't justify that argument. I have seen many question the QA/QC portion of LED's, but never with any real measurable outcomes of difference between seller/supplier/manufacturer.

For instance, are they following ISO 9001:2008? and if they are, the standards are already so high that deviation from manfacturer to manufacturer can be minimal, how high will variability be? Within the same manufacturing process?
How can standards from different protocols be integrated for comparison....none of these questions get answered on quality or control, it is just assumed.


I used to make snowboards/skateboards in an earlier life. Kemper and K2, same shit, different snobbery, same core manufacter in the early 90's, me. Same defected laminate pine cores [the worst]. Yet, K2 is right up there with the most expensive snowboards out there globally and is Kemper even still in business???? lol [Who even remembers Kemper?] We also made foam cores for Burton snowboards too[cheap ass foam cores too, right around when they started marketing their "core" technology, that we made 3,000 miles away, lol] . I just think that assuming Qa/Qc control without proof of the pudding, nulls the argument.....a little. Snowboards are a long ways away tech-wise, but the marketing scheme is still the same.......


On the other side of the coin, I read a lot on reef sites, because they are going off on LED tanklighting and have been for years. There is a user named AC-RC on Ebay and he is still referred over and over again after years of business; selling the same kind of die chips.

I would think the downfall of the setup COULD be, just the shitty cheap Chinese drivers that seem to fail, even with minimal current increases [heat].

I would think the downfall of the setup COULD be, just the shitty cheap Chinese drivers that seem to fail with minimal current increases [heat].

Click to expand...

on the other Hand i also read about a lot of reef ppl saying they never had an issue with those cheap Drivers what so ever. in the negative comments of the seller i found like 3-4 ppl saying it was defective, so i guess there is still a relatively small % gamble there. I mean i like customers can comment the purchase on ebay. If 100 out of 27K+ r unhappy because of Long shipment mostly or a defective item i can live with that.

lax123 said:

on the other Hand i also read about a lot of reef ppl saying they never had an issue with those cheap Drivers what so ever. in the negative comments of the seller i found like 3-4 ppl saying it was defective, so i guess there is still a relatively small % gamble there. I mean i like customers can comment the purchase on ebay. If 100 out of 27K+ r unhappy because of Long shipment mostly or a defective item i can live with that.

Click to expand...

Dammnit, see there I go making an assumption after lecturing on said bullshit, lol.

I have been wanting to run the same diodes on cheap CPU coolers and Meanwell Ldd's.

Why don't you guys buy electronics for an electronics suppler? I just don't understand the hole idea of "It doesn't matter coz its cheap". Why do you think all the panels on the market are pretty much crap and anyone with half an idea could do a better DIY project?

I also don't think you realize how these things are made, its almost the same level as Computer Possessor Chips. For example Bridgelux's R&D department dropped some serious cash to have there own Die manufacturing fab here in CA, all the stupid china people do is steal idea's and processes from the ones doing the research and spending all the time and money making it happen. Why don't you want to support them?

Snowboards are not the same as COBs, if you guys want the world to be ruled by china then keep not giving a fuck...

Shit Chinese setup....with SMD 50 and 30w chips (and a couple of 10w) crap heatsinks, crap drivers....Veg cabinet running 18/6 since Novemeber 2012....

The point....might not be as efficient as a more expensive chip(s)...but it gets the job done.

Well I guess I am on a different page to most of you. I only aspire to reach the highest level possible with my limitations, I will not settle knowing there is something better I could achieve. I don't really know why its just my silly ways.

"highest level possible with my limitations"

My limitations for going with this setup....available money and seeing if they worked (curiosity)

and i will never settle when it comes to LED's...thatz part of my fatal attraction...

But small steps to get to greatness.....

If only I could tell you what's in store for my next grow but you will have to wait, I haven't even seen my first flower yet :O

Actually because a lot of people have not grown with LED's or are just getting into them....curiosity is a big reason why they choose what they do.....'just to see what will happen'