Well I mean, from a hypothetical standpoint, how do cob watts and driver watts relate? The part I think I'm having trouble with is understanding how many watts of driver power is needed per watt of cob power?
Let's say you are looking at a vero29 which runs at 37 volts. If you connect it to a 0.7A driver you will get 25 watts from the cob, if you connect it to a 1.05A driver you will get 37watts, if you connect it to a 1.4A driver you will get 50watts. Remember to look for constant current drivers.
Ahhhh! Ok, I think I get it! Example: China COB 100 watts @ 3.6A (3600mA) Soooo... for efficiency I'll run it off of a constant 1.05A driver, I'd get *in theory* about 29.1 watts per COB?
You gotta look up the voltage of the cob and the amperage range. I have no idea what you looking at. That's why most people stick with vero or cree as those have been tested and whatnot. If you wanna go cheap first, look up vero 18.
Ahhh! Vero 18 looks much more affordable, $20 a piece instead of $40. http://www.amazon.com/gp/aw/d/B00HVOIKD2/ref=mp_s_a_1_11?qid=1454457664&sr=8-11&pi=AC_SX118_SY170_QL70&keywords=Vero+3000k I'm going to go with the Vero 18, since I know it's a quality product. It says it's rated 4K lumens at 1.05A, is that at 100% or what it is meant for at 50% efficiency? How do lumens decrease as amperage is decreased?
I found this part with the #digikey mobile app. http://www.digikey.com/product-detail/en/BXRC-40E4000-F-23/976-1271-ND http://www.rollitup.org/t/diy-cob-led-calculator.890214/
Ahh, I see now. They can handle 2+ amps, but obviously I'm going to stick with the lower amperage of 1.05 for longevity. What do the headers along the top row stand for? (The "lm25c", "lm50c", "vf's") ...and I'm still a little confused about the drivers. let's say I have a couple drivers chosen with a constant current of 1.05A, but they have different listed "wattages", how does that factor in? Is that the max pout draw that the driver will allow to be pulled total?
@NewRoom go with Vero 29 instead of Vero 18 the 29's are $23 the Vero 18 aren't worth the time and effort my friend SupraSpl tested them and they performed poorly.
I'm still confused on the driver wattage and what they mean. If the output current is within the desired range, how does the driver wattage come into play? Like, let's say a 30w and a 50w driver are sitting in front of me, and they both have a constant current of 1.05A, how will they effect the cobs?
The first driver works up to 30w, the second up to 50w. Since they are both 1.05A, the first one can support a cob with a voltage up to 30/1.05 and the second one can support a cob with a voltage up to 50/1.05. Voltage x amps = watts Look up some threads on how people have done the usual configurations. If the math is not clear for you, stick with what's already done.
The founder of BML Horticulture and Illumitex, Nick Klase, has started yet another led grow light company called Fluence Bioengineering. Their new SPYDRx is pretty sweet lookin' lol. It's cheaper than the old BML SPYDR and they ditched the blurple spectrum for white. Check it out: https://www.fluence.science/product/spydrx-plus/
I think so far I prefer the purple spectrum. Who wants to waste energy in producing a light frequency your plants are not going to use.? More heat, more light, more energy. I feel the specifically designed COB's instead of 3600k,6500k or whatever full spectrum LED. While I don't find them useless these COB's are certainly more common, and IMO, less efficient when it comes to grow lights. You can get 3600k 6500k LED's cheaply, so the product should reflect that outsourcing.
Here are cople threads for you to read and make conclusions. Read first though. http://www.rollitup.org/t/cxb3590-1500w.878136/ http://www.rollitup.org/t/top-bin-cob-comparison-2.897765/ http://www.rollitup.org/t/why-do-some-guys-wats-to-still-use-mono-led-with-cobs.889223/
I've already read through a lot of those threads, I lurk there frequently. I don't have any conclusions as of yet, I just know what I am preferring. I am taking a different approach to LED lighting that will utilize timing cycles and modulation to produce a quality of light, in the needed bands, at up to half energy. It's just theory and ideas, but hope to have some practical application data soon. Here is one of my 3rd week of flowering from 50watt LED Purple grow spectrum.
I'm no expert, but from what I understand, although blue and red light will drive photosynthesis, plants can efficiently use many other colors of the spectrum. A combination of light spectrums will also have a synergistic effect where the whole is greater than the sum of the parts, called the Emerson effect. PAR graphs showing chlorophyll /b peaks in the red and blue spectrums are misleading. The McCree Curve of Relative Quantum Yield gives a better picture of what spectrums of light plants use. White cob's are nice because they are very efficient and DIY friendly. I thought that the new bml light looked like a nice design.. passive cooling, nice spread, nice spectrum. 2.08 μmol/j is a very good efficiency, better than double ended hps at 1.70 μmol/j. The price isn't too bad. $1500 is not much more than what one would spend on a large 12-16 cxb cob build for a 4'x4' space. http://agi32.com/blog/2014/12/10/photometry-and-photosynthesis/ http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0099010
I'm not buying anymore lights anytime soon, but I was just interested to see what the diy'ers thought about it. Seems like a decent option for folks that don't want to diy but still want a nice light.
Thank you for the post and reference information. i didn't opt for high wattage because it is more expensive, not just to purchase, but to operate. If I felt I needed a huge wattage in order to grow, I'd would have built something that was more efficient, cheaper to offset the cost of ownership, but I am growing I think pretty good under 50watt at the wall panels. I'm going to build my own lights because I have the bug, and when I do, most likely, unless something changes, I would use something from Aliexpress in the 100 to 600 watt range. i'm very interested in the synergistic approach, it just feels right that plants would love to use white, and I like the idea as it allows me to work and spot things easier on the leaves and such, but I don't want the added energy use, heat, and cost of ownership.
The blurple cob you are using has very poor efficiency and 6500k is not the most used it's 3500k you can veg and bloom. I run Cree CXB 3590s they run 56% efficient what does yours run? Lol I know you don't know that.
I'm not using a blue purple COB. but if I wanted to know what its efficiency was, I'd do the math. What I do know, I got these cheap panels and they pull 49 watts at the wall and my grow so far loves them. I love Cree LED's, and who knows may use them. I will buy what is cheapest and try to make it work like the best, that is what I like to do. I'm going for the ACME style of failure, and eventual success. I always do because I am challenged to get the most for the least on a consistent basis. You can't beat 50 bucks for a panel that grows sticky thick frosty dense buds. At least in my grow anyways so far. Eventually I want to make a few trick panels with built in timers for LED's that rise and set like the sun, and utilizes arduino or pi in a PWM circuit for over driving LED output, and gaining efficiency. With all the ancillary support power that is drawn for some builds I have seen, while there may be efficiency, there is still the consumption.