Strip LED Spectrum/Wattage Needed for 1lb Yield w/Average Genetics?

[Douglas.Curtis]

I'm looking to build a 32" x ???" LED cabinet and want to design it around strip LED lighting. Goal is for a yield of around 1lb per crop. The genetics are going to vary, so will yield. Having a light powered for sativas, and able to be dimmed, may be a useful option.

The figures for wpsqft and LEDs range from 25-35, and (as far as I can tell) it's based on quality of the driver/chips/layout and correctness of the spectrum. I don't care about budget for this light, I'll be building it piece by piece.
Questions:

1. What spectrum, or combination of spectrum, produces hps 'type' flowers with high flower to leaf formation, and what wattage does it require to achieve a 16oz harvest?
2. Which manufacturer has the highest quality strip leds?
3. What bins are the most efficient for this spectrum?
4. How deep will these penetrate a moderately deep canopy? (please include strip layout & wattage with answers to this, for reference?)

Do you have something similar running? What spectrum is it and what do your flowers look like? Downsides to your strip or driver choices?

Thank you so much for any feedback. I'm amazed to see what's being built and how well they're growing cannabis.

 

[OakyJoe]

subbed

 

[f-e]

4' is a typical tube length. About a dozen would do it.

Is greater detail, a pound is about a square meter on a dismal day. So 36x48 gives you your meter. 48' is common for fluorescent lamps (36w) and so many manufacturers produce retrofit led lamps of this dimension. I would really like to put about 450w over the meter, and maybe 550w. I'm yet to look, but imagine the led tubes to be around 30w each.

3k is the right temperature. No need for a high cri, as it effects efficiency too much to be worth it.

Maybe you should be looking at the household lamps though, not tubes or strips.

 

[Douglas.Curtis]

36x48 is doable, and hadn't thought about retrofit lamps for this thanks. Is there a 3K retrofit known for high quality? I can see swapping lamps in and out being a plus.

 

[popta]

4' is a typical tube length. About a dozen would do it.

Is greater detail, a pound is about a square meter on a dismal day. So 36x48 gives you your meter. 48' is common for fluorescent lamps (36w) and so many manufacturers produce retrofit led lamps of this dimension. I would really like to put about 450w over the meter, and maybe 550w. I'm yet to look, but imagine the led tubes to be around 30w each.

3k is the right temperature. No need for a high cri, as it effects efficiency too much to be worth it.

Maybe you should be looking at the household lamps though, not tubes or strips.

Household lamps use low cost LEDs that have lower efficiency. (They're less efficient than HIDs even) Household bulbs are 100 lm/w while the better LEDs products are currently 160-180 lm/w.

 

[f-e]

Household lamps use low cost LEDs that have lower efficiency. (They're less efficient than HIDs even) Household bulbs are 100 lm/w while the better LEDs products are currently 160-180 lm/w.

I can't say with any certainty how efficient household lamps are. I know they must be over 200lm/w in Dubai. Which has been law for years. Today, my supermarket has 12w leds that meet the 1521 lumen standard, set for leds to replace 100w incandescents. A job they do behind a diffuse globe that looses ~30% of the leds output. One could say 160-180 lm/w leds were in use.

What I do know, is people are seeing more grams per watt using them than hids.
grow diaries>micro grows>cfl led comparison

 

[f-e]

36x48 is doable, and hadn't thought about retrofit lamps for this thanks. Is there a 3K retrofit known for high quality? I can see swapping lamps in and out being a plus.

Phillips/osram/sylvania they will all sell them. No point looking at hydro outlets for these though. Try an electrical wholesaler.

They might be better mounted with terry clips and wired direct, than sat in fittings. They won't be energy dense, so you may be cramming them in.

I have looked at building light walls with them, some cable ties and wheeled wardrobe poles (sounds expensive, but $10)

 

[popta]

I can't say with any certainty how efficient household lamps are. I know they must be over 200lm/w in Dubai. Which has been law for years. Today, my supermarket has 12w leds that meet the 1521 lumen standard, set for leds to replace 100w incandescents. A job they do behind a diffuse globe that looses ~30% of the leds output. One could say 160-180 lm/w leds were in use.

What I do know, is people are seeing more grams per watt using them than hids.
grow diaries>micro grows>cfl led comparison

That Dubai thing is a special project that has nothing to do with the bulbs in your supermarket. Those use very expensive LEDs and put out very low light levels (which ekes out even more efficiency). Those bulbs are expensive as hell. The very best ones in your supermarket may get a little over 100 lm/w, but some are a little under and as a whole they average 100 lm/w. Not sure why you say you can't be certain, it always says how many lumens they make and how many watts they use. For example:

https://www.homedepot.com/p/EcoSmar...ulb-Soft-White-8-Pack-B7A19A60WUL18/303574541

As for the guys growing with screw-ins instead of HIDs yeah I've seen them on here and I don't know what's going on there. I figured they just couldn't be bothered to go to the grow store and buy a light.

 

[popta]

(that LED bulb makes 800 lumens from 9 watts for anyone who doesn't want to bother going to the home-depot page. I probably should've typed that out)

 

[Koondense]

Never had led strips but considering some general specs, the logic would go this way...

Expect 1-1.5g/W, you'll need 350-500W of power to grow a pound. Let's say 500w.
For that to be in 25-35w/sqft you'll need an area of approximately 15sqft, so with one measure of 32", the other will need to be around 2,5x 32", so let's say 6 feet.
But from my experience with cobs, you can grow 400g in a 2x4tent so the numbers will always be just approximations and some times confusing.
Regarding spectrum, personally I'd have a combo of 4000K(80cri) and 2700K(95cri) in 1:1 ratio, both dimmable separately.

Hope it helps.

Cheers

 

[Douglas.Curtis]

Never had led strips but considering some general specs, the logic would go this way...

Expect 1-1.5g/W, you'll need 350-500W of power to grow a pound. Let's say 500w.
For that to be in 25-35w/sqft you'll need an area of approximately 15sqft, so with one measure of 32", the other will need to be around 2,5x 32", so let's say 6 feet.
But from my experience with cobs, you can grow 400g in a 2x4tent so the numbers will always be just approximations and some times confusing.
Regarding spectrum, personally I'd have a combo of 4000K(80cri) and 2700K(95cri) in 1:1 ratio, both dimmable separately.

Hope it helps.

Cheers

Greatly appreciated. Until I find a solid water cooling solution, I'm shying away from cobs for now. The heat sink/fan combo is not something I'm liking right now, which is why I'm looking to switch to strip lighting.

I've grown under the cheapo SIL house lights with 2700k, and it's decent flower formation. What's your experience with the 4000k for veg and the average hybrid? Stocky stem and branch structure, without micro short node spacing?

I need more information on depth of canopy penetration as well. Scrog is a consideration, since the screen won't be too deep to manage. It will also help with the lower plant numbers I have to work with. If I find the time to do some research, I'll be sure to post up what I find.

Thanks again everyone, apparently I've been dealing with a rather bad case of ADHD all these years. Your input is greatly appreciated.

 

[Koondense]

I have some experience with vegging under led and cfl of 6500, 4000, 3000K and flowering under leds 3000, 6500K.
Honestly,there are differences mostly in early veg, later in flowering the growth pattern differences were less visible to almost non existent. I just finished a cycle with lemonade og, one plant had a 6500K cob above it and looked identical to others under 3000/3500K cobs.
I wouldn't worry much about it, just mix the CCTs to get a broad and even distribution with good intensity, in my opinion 4000(80cri)+2700(95cri) is the way to go, maybe 5000 or 6500K instead of 4000 will also work well.

Or just get a couple of QB kits 3000/3500K and your plants will love them.

Cheers

 

[popta]

If budget really doesn't matter like you say, why not just buy a fluence or something? Nothing you cobble together with strips is going to be as good as that.

Most strips are meant for office lighting, intended to replace fluorescent tubes. That means they use white LEDs only (not whites plus reds like a horticulture light) and also means they don't use very many LEDs per strip (because the fluorescent tubes they're matching put out pretty weak light). The only white + red horticulture strip I've seen on the market is Samsung's, but they went for an unusual spectrum with that one. Looks like they tried to make a one size fits all strip that would be useable for the lettuce growers.

 

[Koondense]

That would be my advice too, if budget is not limited. But i understand the space is the limiting factor so would rather advise to get some QB kits.

 

[Douglas.Curtis]

LOL budget is not limited because I'll be buying it piecemeal and over an extended time period. No way I can cough up for a top of the line pre-built. lol Thanks though Great suggestions, really appreciated.

 

[methias]

Did quantum strip led board

Did quantum strip led board

Hello Doug ,

I did much the same building my grow hutch.
Piecemeal, (while growing) slowly improving and redesigning as money allowed.

Started with cfl in the spare bathroom.
https://www.icmag.com/ic/showthread.php?t=140141

Next I went to my garage and under my work bench I set up shop.
The heat from the cfl's was too much so I decided to try led's.
I tried those COB's with the drivers on board and heat sinks but they died one by one.
Next I tried 50 and 100 watt COB's with separate drivers but they didn't last either.
I decided to build a box 34"x34"x80" with an exhaust fan up top blowing into a carbon filter.
I hung what COB's still lived and purchased a Mars hydro 300 watt unit. It really pulls about 125 watts liars.
I then purchased a HLG 65 4K quantum board. Good light low heat and actually draws 65 watts.

That gave me an idea.
I picked up a few pieces of sheet aluminum, ordered up some bright led strips (12 volt) and a 12 v 100 w switching driver. I stuck cut strips onto the aluminum about 1/4" apart and soldered them together. I made 2 small red boards, 2 small white boards from both 5k and 4k strips, 2 10x12 boards with a mix of 35k white, some red and blue.
I got an aluminum cookie sheet $1.50 and covered it with white 5k strips.

I quickly amassed more boards than the driver can handle so I got a Meanwell 12-350 switching driver.
I like 12 volts running things. Your fans likely will be 12volt. If a fan driver fails with the cobs, you loose the cob. This way I am no longer loseing leds.
Next I got some 12 volt 50 watt cobs, put them on the heat sinks w/ a fan and plugged it into the Meanwell.
https://www.icmag.com/ic/showthread.php?t=351659
Finally I made a turntable that rotates once every 8 minutes. The motor is (you guessed it) 12 volt.
Now thanks to the DIY quantum boards and turntable everything gets equal lighting. Even the usual soft popcorn underneath the canopy bulk up. The blinding bright light as I open the door reminds friends of close encounters ship interior.

My best harvest from this box was 5+ Oz of great strawberry diesel. That was after losing her top cola (over an ounce wet) to fungus

I just set up a clone area and made a light for it from some RGB strips, a 3500 strip a blue strip and some 5K strips.

That provides enough light for mom and the 2 cloning buckets I made.


So good luck with your build. You don't have to break the bank and you can get massive amounts of light from DIY quantum boards..

Vape on

 

[Douglas.Curtis]

Greatly appreciate the input, Thank you Methias!

 

[Lapides]

4ftx2ft array. Pulling 390 watts from the wall as per the Kill-A-Watt. Chilly nighttime temps and no co2 1 plant in a 25 gallon pot of dirty nasty soil yielded 7.25 ounces of CRAZY OILY weed, it shared the light with another plant. I think the diodes cost 7 or 11 cents a piece shipped very quickly from China. 4000K Samsung LM561C.

 

[Douglas.Curtis]

Beauty!

Your build thread is my inspiration, thank you!

 

[SandyFantasyman]

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