Help design a LED for my cab

Hi, all.

First post here but old member of grass city.

I recently was given clones that rekindled my hobby and Im in need of some guidance. I have not grown in years but am starting to catch up on new indoor tech. I have been consuming information on LED's specifically for weeks now and would like to build a fixture for my flower cabinet with some help. This will be specific to my set up so hopefully not redundant. I hope this will serve as information to others, as many other threads here have helped me so far.

I have a two cabinets. One for veg and another for flower. We will be focusing on the flower cab this thread and designing/ building a custom light to suit my needs.

I have grown in the past using HPS/MH overhead and floro side lighting all together and that seemed to produce the best quality product I have ever grown. So I am a big fan of mixed spectrum, quality over quantity, but would appreciate non-airy flowers. I plan on using LED and PL-L in a combination to achieve a more diverse spectrum, unless someone convinces me LED alone can fulfill what I am after.


Scope:
Design and fabricate a DIY LED/PL-L light for a flower cab.
LED= main lighting PL-L= supplemental. I will use either 2, 3 or 4 Pl-L's depending on what we discover about LED's in my specific situation.


Dimensions:



Current grow has 22" head space from the screen to the lid of the box. I hope this won't be an issue this grow but future grows should have more head space as I put theses plants in later than expected (box was being built).

Heres some more info.

I should state that im aware of the cob and most likely going that route. Height and a low profile will be incorporated into the design and fans for cooling.

I would like to build something similar to this but with newer LED's : https://www.icmag.com/ic/showthread.php?p=4857222

Here are pics of the current grow. Honey boo boo under a 4 lamp 2ft t5HO. The light will be moved to the clone veg box once the new flower light is in. Soil is a mixture of yard dirt for filler from my garden, Fox Farms oceans forest and amended with my own food scraps compost.




So can anyone help me calculate options for a PL-L / LED combination. Should I rely on one spetrum for a particular light? ie: use pl-l for blue / ubv and LED's for red spectrum?

It seems the cree cob's seem to be the best out right now. I dont mind spending more on the cob's, I'm fine with cheap Chinese drivers to dave costs. So lets start with cob's as the building block. Red and white seem to be a good option for led is PL-L can provide uvb and blue.

Copy Realstyles LED and be done with it. It is a proven winner using the best current technology. Use the KISS method and don't ever engineer it.

The less time you spend on designing the lighting system, the quicker you can grow ganja.

Time spend designing isn't a problem. I will have it finished for this run or next clone batch. The green is already growing.. Im also a designer by trade so designing it is actually enjoyable. But thanks for the link, haven't seen that thread yet.

I think I can pull off that linear design in between the PL-L lights. I will have to run less cob's in my small space obviously. I haven't read through the thread fully to see what spectrum and foot print the chips will do.

You're gonna need 150-200W of cobs in your cab.
I think a range of 4-6 CXBs(3070/3590) and a driver like ELG150H-C1050 or a HLG185H-C1050 will do wonders in there.

If you're in EU contact me for any info.

I agree with Sforza. Use the Cree cxa3590 5000k, at $48/each x 6 = $300 six will create a 1,000w fixture. You will need a couple of $10 drivers, a $75 power supply, 40 " heatsink holders for the cree's at $10, and some paste and 18 gauge wiring and you will have a unit producing 1,000w HP/MH power with much less heat and electricity usage.
good luck with your new direction. I would recommend to follow Realstyle as he had no previous background.

The problem with copying designs is adaptability.
RS already copied who knows who's design on RIU and has nice results but his tents are way bigger than this space in consideration.
Using basic math one can find more apropriate ways of building lights for various spaces.
Copying is just boring and many times useless.

Edit: Copying and making errors(having no clue) can be very dangerous!

Consider modular approach. Based on your height you should probably consider 400w as you will need 16" from COB to foliage for best uniform coverage. Consider watts as you would MH/HPS usage. cxa3590 is 75-150w I believe. Add what you want at about 80% efficiency rate and choose based on that. A driver can drive up to four COB leds, but spreading them out may mean independent heatsinks with fans vs, group of COB's on one heatsink.

Agree, coping is boring and the design needs to adapt. I like the solid rectangular extrusion realystlye's light has as opposed to mounting a single cob on a square computer heat sink with a fan. I like the simplicity of less/ larger fans. Cree cxb 3590 seems to be the best option right now. Going to try knightbrite on ali express. Going to sketch some drafts of light layout.

I have been looking at parts and prices today for the cobs drivers and heat sinks. I think I will start with 4 COB for this cab. CXB 3590

I still like the idea of PL-L lighting incorporated so that is still in the air. I have to match ballast models to light wattages. The fulham workhorse is a good option. 3x 55w PL-L's would be nice to compliment the 4 COB's in-between.



I could also run 4x 55w PL-L's - 2 over head and 2 lower for side lighting which may be nice for better penetration.

The heat sink in the drawing is based off of heatsinkusa.com 5.8" extrusion. Is 5.8" x 15" enough if I run two COB's with a fan? and would 5.8" x 15" alum. heat sink be enough to run three COB's if I want to upgrade to six in the future? Also, opinions on using all 3500K, all 5000K, or mixing both for a 4 COB set up.

Looks nice,
so you'll have 165W from PL-Ls + how many Watts do you want from leds?
The 3000K would be my choice because they have a bit more red light than 3500K(more photons in total). With additional 100-150W it will be almost too bright without dimming the cobs.

Still wrapping my head around things. Not sure how many watts I want. It seems 6 should be the max for may space based on what others are using for larger foot prints, but I will be going with 4 this time. I hope the two aluminum heat sinks (5.88" x 15") will be enough for 4 right now (2 cob per heat sink) and hopefully enought for 6 later (e per heat sink). Im not all up to speed on the dimming and controlling the amps. Thats next up on my research. What are the differences in the 36 vs 72v COB's?

As far as kelvin I'm gonna look at what the PL-L's can offer in spectrum. There are a lot of color spectrums available it seems so finding one to compliment the LED is the goal. Ill try to find some pics and overlay them in photoshop to give me a guesstimate of spectrums. Anybody know off the top of their head what PL-L or spectrum in general might compliment 4 3000k or 4 35000k CXB's?

Im most likely using the Fulham workhorse 8 which is rated for 220w. I believe I can run 1- 6 lamps depending on the watts.

here are some layouts

4 cxb 3000k CB are 11K lumens according to cree data sheet.
11,000 x 4 = 44k
3 PL-L (3x55w) = 165w PL-L @ 3650 lumx 3 = 10950
combined: 54,950 lum


4 cxb 3000k
44k lum
4 PL-L. 220w (4x55w) @ 3650 lumens = 14600
combined: 58,600 lum



I put a square foot circle around the cobs to show light spread. Six cob would be ideal but I can always add another 2 cob panel to the center. For now the goal is to mix lighting sources for diversity so the 4 PL-L's will fill in where the cob's won't.



I'm sure some of you are questioning why I'm spend money on additional pl-l vs adding more cob's and I don't have a good answer.. other than I want to try it out as an experiment. I have mixed light sources and spectrums in the past with good results but never with these two combinations.

Sorry about the dimensions on the side. My art board included them in the export, my mistake.

PL-L Lights are on their way. Went with 3 instead of 4. Apparently fulham no longer list you running 4 55w PL's on a 220 w ballast. There seems to be debate about the nature of the change and a lot of people still run 4 55w but I will stick to 3 for peace of mind. Here is my shopping list for the PL-L side of the fixture (leds to come)



I went with the cheap bulbs which happen to be the only correct spectrum options. I imagine a better phillips bulb in a slightly off spectrum might work better but for now its cheap and well see how goes. I need to better research on what brands run well. I went with 2 6500k and 2 4100k for now. I can always buy some 3000k closer to the end and play with mixing spectrums.

the leds will be the last edition as they are the most expensive option to me. I still plan on running 4 cxb3590''s.

Q: The cba's are a bit cheaper, are the B's worth the extra?

Q: Also worried on height for this grow. How close can you get with the cob to the plant before stress or burn?

The cxb's are the second generation I believe. The newest edition. I run 4 of the 3590's @ 1750 ma and according to the cree pct tool i have 34000 lumens combined. To push them to 44000 lm's i think you have to push at least 2400 mA. Then you lose lm/w and thats less efficiency, more heat to deal with at higher wattages. Plus finding a driver to push them at that current is expensive. At 1400 mA you achieve much more bang for your buck lm/w. Cheaper driver can push all 4 as well. Plus the hotter you run them, the more space you'll need between lights and plants.Sorry if i bummed you out. Just want you to be aware of the decisions you make building a diy lamp. Trust me you don't need that extra 10000 lumens. Hope you are successful with your build.

Peace, Roast.

After looking at box dimensions, you might be too small a space for 3590's. I think 4 cxb3070s pushed at 1050mA would be a much better fit for your cab. Hope that's not too hot. Play with this http://pct.cree.com/dt/index.html

Peace, Roast.

monarch said:

Im not all up to speed on the dimming and controlling the amps. Thats next up on my research. What are the differences in the 36 vs 72v COB's?

As far as kelvin I'm gonna look at what the PL-L's can offer in spectrum. There are a lot of color spectrums available it seems so finding one to compliment the LED is the goal. Ill try to find some pics and overlay them in photoshop to give me a guesstimate of spectrums. Anybody know off the top of their head what PL-L or spectrum in general might compliment 4 3000k or 4 35000k CXB's?

Click to expand...

I am using the 3000k CXB3590 and they are fine. The 3500K are also fine. Not that much difference between them. Real intense light seems to be more important, as far as I can tell, than having the perfect light spectrum. It seems more people are liking the 3500K COBs now, perhaps because they might be a little better for vegging and flowering.

Use the Meanwell HLG185H-C1050 driver as suggested above, which is the 1.05 amp version, or use the .7 or 1.4 amp versions. Get the model that ends in A and they have a built in dimmer that adjusts from a little more than the rated power down to about 50% of the rated amps. I thought the dimming function would be useful, but at all stages of growth, more light seems to make for happier plants, so I never dim mine. But is nice to know that you can dim them. Realstyles uses the 72 volt version of the CXB3590 and the .7 amp version of the Meanwell driver. During summer he dims his drivers down to only 350 mA, because he does not have air conditioning so he wants to put a minimum of heat into his room.

The 36V and 72V CXB3590 COBs are the same, except one is 36 Volts and the other is 72 Volts. The two types of COBs are equally as effective. The difference is in which drivers you use. I have some of the Meanwell HLG185H-1050 drivers that I bought at a good price on Ebay. As I recall, they put out about 144 volts of power. So I can run two 72V per driver, or four 36V COBs. Roughly, 72 volts times 1 amp equals 72 watts so two COBs will get me about 144 watts of power. Four 36V COBs times one amp, will also get me about 144 watts of power, but I have invested twice as much money in the 36 volt COBs, so why would anyone do that? Because when you run the COBs at lower amps, you get a little more efficiency, which means more light and less heat, which is important when you are growing in a little cabinet. Whether you run the four 36v COBs using one driver or two 72V COBs using one driver, you are going to get about the same amount of light out of the light.

So there is no free lunch. Get lots of 36v COBs and fewer drivers and then run them easy and get long life and little heat or get fewer 72V COBs, more drivers, and get more heat and perhaps a little shorter life, but more light from each COB.

If I were you, I wouldn't mess with the PL-L crap. That is a waste of time and effort. The COBs are going to grow some excellent ganja all by themselves. The PL-L is not going to help or hurt, but you are not going to know that and perhaps are going to think that it is the PL-L that is really doing the job.

If you have your heart set on using PL-L, and it is obvious that you do, why not run half the cabinet using COBs and the other half using the PL-L? You will soon see that you were wasting your time on the PL-L and go full COBs.

Straight CXB3590 COBs, at or a little above the recommended 50 to 100 watts per square foot, with no extra doodads like the PL-L or little red or UV or infrared or whatever works very well. If it ain't broke, don't fix it.

I am far from an expert, but by reading a lot of posts by a guy using the handle of SupraSPL, I was able to learn enough that I was able to design and build a few different styles of lights that work well.

I agree, it is fun to try to come up with something better than anyone else has been able to do, but what I probably really did is come up with some sub-optimum designs. But it doesn't matter. Building LED COBs is not yet an exact science and they make a heck of a lot of light without using too much electricity, so even the bad lights grow some good ganja.

If you want to do some research, google SupraSPL and read his stuff. Realstyles asked SupraSPL what he recommended and instead of screwing around and trying to reinvent the wheel, Realstyles got busy and started building lights using SupraSPL's suggestions and grew some nice weed.

monarch said:

PL-L Lights are on their way.
Q: The cba's are a bit cheaper, are the B's worth the extra?

Q: Also worried on height for this grow. How close can you get with the cob to the plant before stress or burn?

Click to expand...

Sorry, I did not see that you already had ordered the PL-L when I wrote the previous post. Still don't think they are as good as COBs and you should put them in another cabinet or on one side of the cabinet so you can see and compare with your own eyes which lights grow better weed.

The B's are the latest and greatest and cost more because they are better and I think that they are worth it but it depends on how much money you have to spend on your hobby. I bought some CXA3590s when they were the latest and greatest and they still work fine. I also bought a couple Vero29 second generation and they are less expensive and work well too.

Over Christmas I went out of town for two weeks and left my little plants growing under LED lights being watered using blumats. When I got back I found that one plant had grown right up into the little reflector and up against the COB. The last inch or so was toasted, but the rest of the plant was fine. I cut off the burned area and moved the plant and it flowered nicely.

I have very little head space in my grow area so the plants get very close to some high powered COBs, as in 1.2 amp driver with a 72V CXB3590 for about 100 watts each, and there is no burning and none of the bleaching that I had heard about. If you put your hand directly under the COB you can feel that there is some heat coming off it, but it is not real hot. If you mess up, as I have and touch the surface of the COB, it is hot, but it did not cause a burn.

Sforza said:

Sorry, I did not see that you already had ordered the PL-L when I wrote the previous post. Still don't think they are as good as COBs and you should put them in another cabinet or on one side of the cabinet so you can see and compare with your own eyes which lights grow better weed.

The B's are the latest and greatest and cost more because they are better and I think that they are worth it but it depends on how much money you have to spend on your hobby. I bought some CXA3590s when they were the latest and greatest and they still work fine. I also bought a couple Vero29 second generation and they are less expensive and work well too.

Over Christmas I went out of town for two weeks and left my little plants growing under LED lights being watered using blumats. When I got back I found that one plant had grown right up into the little reflector and up against the COB. The last inch or so was toasted, but the rest of the plant was fine. I cut off the burned area and moved the plant and it flowered nicely.

I have very little head space in my grow area so the plants get very close to some high powered COBs, as in 1.2 amp driver with a 72V CXB3590 for about 100 watts each, and there is no burning and none of the bleaching that I had heard about. If you put your hand directly under the COB you can feel that there is some heat coming off it, but it is not real hot. If you mess up, as I have and touch the surface of the COB, it is hot, but it did not cause a burn.

Click to expand...

I know led are superior but Im set on PL-L for a few reasons relating to diversity.

#1 I can use them for multiple side lighting options; horizontally and vertically. leds all around the cab is pricey. So the floros will provide an economic alternative.

#2 They can always go in my veg cab for some great lighting. veg cab it 35 w x 18 d x 30 h ish

#3 Its a fun hobby. I want to try out experiments. Not side by side comparatively but together. I don't see it hurting in any way to diversify spectrums. Floros are niche and leds do provide great output but I also want diversified lighting sources. Its a small space so bouncing around some extra energy will be fun to experiment with. I can try running straight led vs mixed in the future and post results.

And yes I haven't seen this lighting combination specifically, nor do I feel I am blazing a path of innovation. Im sure there is already lots of threads of debate on it already but it should be beneficial for discussion.


Back to the cob.

Thanks for clarifying the issue on voltage. Four 36v cob's should suffice. Im not concerned about 10k worth of lumens.

Ill look into the 3070 and cxA models as a cheaper option. However, I was under the impression that the cxB 3590 efficiency improvements would be worth the extra. I didn't consider the cxb's being too much light for my cab as another poster pointed out. From other readings it seemed that its better have the power availability but the ability to dim accordingly to negate light intensity and heat issues, while improving the cob life.