# LED Lights Experiment



## bobert

First time ever growing.  Plant is a white widow clone.  Currently using 365 635nm high output leds (3000mcd).  Power draw is 188mA at 117 volts for 22 watts of power and a whopping $11.56 per year in electricity at $.06/kWh.  Red lights will be doubled soon and our blue lights still haven't arrived!  We are attempting to recreate nasa's setup with 92% red and 8% blue.  Current setup has cost $80 in electronic parts (leds, boards, etc).  Guessing that enough lights for a full 3'-5' sized plant would run almost $200 total, no bulk rates, and building it yourself.  Will keep ya posted tho.

The top light carries AC to the board, turns it into dc, and powers the lights.

The bottom board is connected to 2 wall adapter 12V DC power supplies (1 iomega and 1 linksys layin around) that combined actually put out 32 volts.  This board is much less likely to shock you so its not covered.

So far the easiest way is rectified AC, more voltage, the DC board was a pain at the lower voltage.

Heres a picture of day 1:







And a couple of day 13:


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## Mysterious

dude this is crazy looks awsome never seen or heard about any 1 tryin to grow with Led's


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## Mutt

Mysterious said:
			
		

> dude this is crazy looks awsome never seen or heard about any 1 tryin to grow with Led's


 
Here is a link to a company that makes them, but they aren't cheap.
http://www.ledtronics.com/ds/plantled/

I can't wait to see how this grow turns out. Def. has my curiosity.


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## THE BROTHER'S GRUNT

*Whats going on bobert. This is going to be a very interesting grow and i cant wait to see the final product. Be sure to keep us updated with pics of course.  *


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## THEMEDIC

Very nice R&D project bobert, really looking forward to seeing the results you get. Is that the actual growth you got from 13 days exposure from your boards or did you use other types of lighting?do you rotate your lower board? 

this is a definate "subscribed thread"...


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## bobert

Day 1 is the day i finished the first panel of lights and got a clone from the med club.  Started off at 4".  Added second panel of reds on day 8.  Days 8-13 got about 3.5" total growth.  It gets no other light other than some indirect sunlight whever the closet is open.  There has been no direct sunlight since day 1.

Man that ledtronics is expensive!  My current setup is a duplicate of the ledgrowlights.com without the blues (still in the mail).  I was able to build their setup for around $100 (self built red with prebuilt blues) without the benefit of bulk purchasing and manufacturing and they are still selling it for $300 per kit.


Lower board does not get rotated yet.  Plant is deffinately angling the leaves towards that board and the upper one.  I think I'll have to approximately double the red lights by the time it gets around 18" to keep it going.

Everything you see is getting done on 22 Watts total, probably about 15 watts actually going to the LEDS


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## mcdillioh

wow, thats awesome man. ive been wanting to see an LED grow. and here it is. cant wait to see the results.

oh you might want to check out this link. www.besthongkong.com they have some neat stuff at good prices.


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## Mutt

Hey do you have a parts list handy for it? Resistor values, Diode types? Or even better a schematic?


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## AusToker

that is a nice plant man. i wanna see its buds  lights look kool


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## THEMEDIC

Hi-inten white and blue still hover in the $2 range up here..whats your cost?


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## bobert

besthongkong.com is a great place, shipping time is lacking tho 

best prices ive found so far are at www.hebeiltd.com.cn/?p=led.diode ...reds at 5 cents and blues at 7 or 11 cents or something.  The blues are pretty much like radioshacks $4 singles.  Its in china tho so there is a min $25 shipping fee so it is about the same price to go through like, besthongkong for blues/red or even jameco.com or digikey.com for reds. 

Besthongkong sells 48 led high output blue round lights for 12 bucks a pop!

Current process for ac/dc was to connect 60/15 leds in series, power it, monitor current while adjusting a potentiometer, get correct current, disconnect and measure the potentiometer, and then put in the correct resistors.  Almost every set has a slightly different resistor requirement.  Im looking into current limiting diodes right now which may make it a lot easier/quicker.  By the end of this i may write a guide for people.


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## mcdillioh

cant wait for the guide bro. keep up the good work.


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## THEMEDIC

bobert said:
			
		

> Current process for ac/dc was to connect 60/15 leds in series, power it, monitor current while adjusting a potentiometer, get correct current, disconnect and measure the potentiometer, and then put in the correct resistors. Almost every set has a slightly different resistor requirement. Im looking into current limiting diodes right now which may make it a lot easier/quicker. By the end of this i may write a guide for people.


 
I'll assume you limited them to around 30ma each ,so you'd be pulling 1.4Ato1.8A/60LED?...
did you take into account the LED's angle when you mounted them on the board?


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## bobert

THEMEDIC said:
			
		

> I'll assume you limited them to around 30ma each ,so you'd be pulling 1.4Ato1.8A/60LED?...
> did you take into account the LED's angle when you mounted them on the board?



The mA rating is how much current you can draw through the led.  Whether you have 1 led or 60, 20ma is the TOTAL being drawn through them.

Ok,heres the cool part.  If you wanted to you could take one led rated at 1.9V and power it with a 12V supply and 1 resistor.  The led would drop the voltage to 10.1.  V=AR so 10.1/.02= 505ohms  so now we have 1 led using 1.9*.02 + 10.1*.02 =  0.038W + .0202W for a total cost of .24 watts/led.  Using 1 led/1 resistor in this setup would mean 86 watts for 360 lights.

Now lets say i chain 15 of them together and power it with 32 volts.  15*1.9 = 28.5   so at the end of the chain i have (32-38.5) 3.5 volts to work with.  Now i have 15*1.9*.02 = .57 watts   now 3.5/.02=175 ohms   and 3.5*.02 = .07 watts for a total of .64 watts/15 lights

now 360 lights would be powered by 15.36 watts vs 86 watts for the same light output just by using less resistors.

The first board i made all the leds where flat mounted, 10x easier this way.  Second board i tried to have them floating about .25" off the board so we could angle them different ways, kinda works but was an enormous hassle.   Gonna stick to flat mounting for now.


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## THEMEDIC

thanks for the calc's bobert..nice job..I have the blue&whites 4V 30ma mounted at my [email protected] .36watts/led I was looking at 130 watts for a 360 board..more than my battery system would of liked..sound system...you have brighten'd up my cabin..


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## Hick

daaaaaaaamn!...Welcome genius's.. 
I'm still tryin' to figure out how they get 'lectricity to run uphill.


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## Mutt

bobert said:
			
		

> !
> 
> Current process for ac/dc was to connect 60/15 leds in series, power it, monitor current while adjusting a potentiometer, get correct current, disconnect and measure the potentiometer, and then put in the correct resistors. Almost every set has a slightly different resistor requirement. Im looking into current limiting diodes right now which may make it a lot easier/quicker. By the end of this i may write a guide for people.


 
Have you tried looking into IC's to accomplish this for you. National Semi-conductor has a section on this.  

http://www.national.com/appinfo/power/lighting.html


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## FieldofDreams

here check this out, its another forum that has done similar experiments:
http://www.reefermanseeds.com/forums/showthread.php?t=3561&highlight=lights


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## THEMEDIC

excellent link FOD..its a must read..


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## Stoney Bud

Hick said:
			
		

> daaaaaaaamn!...Welcome genius's..
> I'm still tryin' to figure out how they get 'lectricity to run uphill.


 
It does? Hell, I caint even make it fall outta the little tubes. Tried to see how it tastes once.

Won't be doin that again.

Hhahahaahahaha


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## wreckchords

hey, i just signed up so i can see how this experiment goes. looks good. maybe a good idea to keep the LED's in parallel so that if one goes, u dont get the whole lot go out like christmas tree lights, but then again, the do have a very long life expectancy. keep the good work up.


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## Stoney Bud

Hey, I think this is a great thread. I've been wondering about the LED grow light thing for a long time.

I do have some questions. Does anyone know a good tutorial or anything on learning the threory and specs on LED's?

Like how are lumens rated with LED's? Using other lights, it uses the distance of 12 inches as an absolute in the formulas. What is the best "plant" distance the bulbs need to stay at with LED's?

Getting an even amount of red-blue mix would be difficult unless at least 4-6 inches from the plant was maintained, I would think. I may be way off base here but I'd love to learn the science behind this technology being used for growing.

I need information input!


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## Mutt

Here is few PDF spec sheet links I had in my library.
http://www.ledtronics.com/ds/plantled/Commercial-Growing-Analysis-Recommend-s.pdf#search='LED%20Plant%20light%20Specifications'

http://www.ledtheway.com/EnLUX%20growlight-datasheet.pdf#search='LED%20Plant%20light%20Specifications'

https://www.ledtronics.com/ds/plantled/LED-PlantBar_Technology_Comparision.pdf#search='LED%20Plant%20light%20Specifications'

http://www.ledgrowlights.com/About%20us.htm

Most are related to a store bought product. but the principle is there. I got more stuff on it, but this will fill your weekend as it is. lol


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## THEMEDIC

hey bobert..no updates?


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## bobert

Heres a picture from day 23, about 30 minutes after setting up the blue lights.  The plant liked em, with the top leaves raising themselves from about 12" to 15" within 4 hours.  I was planning on doubling the lights but with my current financial situation (yes even at $100 a setup ) it looks like we will be growing the entire plant on 25 watts. (We were at 22 watts blue lights came in around 3.1 watts)

If you grab the picture location you can check out the whole gallery at once.


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## bobert

Here are some stumbling blocks i have hit with comparing LEDS to say...HPS

LEDs are rated in millicandellas which cannot be directly converted to lumens (there are approximation equations out there).

LEDs are directional, some ambient light can be seen through the back of the board and you can't even look at the front with your eyes open.  The light intensity would not be same if it radiated all directions.

LEDs by design give off a huge percentage (i.e. 90%) of their energy as light, whereas a HPS gives most of its energy as heat, and say...10% as light.

If you cut the distance from the light source to the plant by half, you quadruple the light power hitting the plant.  From what I understand, HPS needs at least a few safety feet whereas our leds are anywhere from 1"-12" away.  So, quick calculation says at 3.5" away a HPS light would give 256 TIMES more light to the plant than at 60" (dang heat).  So if we had our current leds at a 60" distance they would have to be 256x more powerful to obtain our current results.

im sure somebody will figure it out someday




			
				Stoney Bud said:
			
		

> Like how are lumens rated with LED's? Using other lights, it uses the distance of 12 inches as an absolute in the formulas. What is the best "plant" distance the bulbs need to stay at with LED's?
> 
> Getting an even amount of red-blue mix would be difficult unless at least 4-6 inches from the plant was maintained, I would think.


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## THE BROTHER'S GRUNT

*Looking good bobert. I have been waiting for you to give us an update on this grow. It freaks me out to see those small lights growing that plant. Anyway be sure to keep us update with pics of course. Great job man.  *


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## mcdillioh

great job and thanks for the update.


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## THEMEDIC

Hey bobert whats up with the girls??updates man!! updates!!


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## Stoney Bud

Hey bobert, I found a calculator on the web that will give an approximate conversion of millicandellas to lumens.

LED LUMEN CALCULATOR

If each of your LED's is identical and produces 3000 millicandellas, and the lights are 180 degrees from the plant, then the plant is receiving about 18.85 lumens per/light using this formula.

At 18.85 lumens per light and 50,000 lumens being the target for optimum growth, then 50K/18.85=2652.5198938992042440318302387268

Or rounded up = 2,653 lights.

With a ratio of 92% red to 8% blue, you would want to have 212 blue lights spaced at one blue after each 12 reds, and you would use 2,441 red lights.

Using the power ratio that you've shown in your first post in the thread, I get 32 cents per/year per/light.

That would be a cost of 850 Dollars a year US.

850/12=71 dollars per/month US per/sq. foot.

This makes me wonder if the lumen calculations are accurate in this formula. That seems like a lot of money per/month for 50K lumens.

Because of what you've said about the distance to the plant being less, I'm wondering if perhaps only say, 10K lumens are needed using LED's. Perhaps even less. If so, then the costs would also drop proportionally.

The common formula for lumens uses a 12 inch distance from the measuring point. With LED's, I'm guessing that 2 to 3 inches may be usable. One sixth of the distance would require only 12,500 lumens per/sq foot. Using the above figures, that would require only a total of 663 lights per/sq foot.

663 lights would only have a cost of 212 US dollars per/year per/sq foot.

I have 20 sq. feet of grow space in my grow room, so it would cost me about 4,240 per/year for these lights? That's 353 dollars a month!

I think that perhaps only one sq ft of lights will provide the needed lumens to as much as 9 sq ft. if so, then only two sq ft of lights would be necessary to light my 20 sq ft.

This would reduce the yearly cost to 424 dollars US or 35 US dollars per/month. I like that number way better.

I'm going to talk to a lighting engineer about this and see if I can find a true conversion. I'll let you know man.

Good luck to you! Lets see some more pics of the girls!!!



			
				bobert said:
			
		

> Here are some stumbling blocks i have hit with comparing LEDS to say...HPS
> 
> LEDs are rated in millicandellas which cannot be directly converted to lumens (there are approximation equations out there).
> 
> LEDs are directional, some ambient light can be seen through the back of the board and you can't even look at the front with your eyes open. The light intensity would not be same if it radiated all directions.
> 
> LEDs by design give off a huge percentage (i.e. 90%) of their energy as light, whereas a HPS gives most of its energy as heat, and say...10% as light.
> 
> If you cut the distance from the light source to the plant by half, you quadruple the light power hitting the plant. From what I understand, HPS needs at least a few safety feet whereas our leds are anywhere from 1"-12" away. So, quick calculation says at 3.5" away a HPS light would give 256 TIMES more light to the plant than at 60" (dang heat). So if we had our current leds at a 60" distance they would have to be 256x more powerful to obtain our current results.
> 
> im sure somebody will figure it out someday


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## wreckchords

do you have any updates? any new pics would be great...


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## makomike

Which one would produce most yield? (HPS/LED) If Led which color bulbs would i want to order (best for the plants)if i wanted to build my own light and where would i order these bulbs and where could i find a place that would sell me long circuit boards (6ft and up) Thansk GUys


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## Smoked Out One

so would the ones from http://www.surplusled.com/Merchant2...t_Code=LED-PLANTBAR-001&Category_Code=_CON_CN work? or how many would I need?


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## 1HIGHGODDESS

very intersting light set up..im considdering ..anyone else already have this ...whats your results?
and any pic's, ,it looks like not much space is needed eaither for set up...

just wondering what does the surrounding area of your set up looks like.


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## Elephant Man

I found an interesting pre manufactured unit, refer to this thread:

http://www.marijuanapassion.com/forum/showthread.php?t=6441

pm me for the link or a mod can post it.


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## StOnEd-On-NL

Very interesting thread. Im no electrician, but the thought of growing with LED's sounds fun. If you could get a board 4ft x 4ft and filled it with those LED's, would that work? that would be great, it could fill my entire growroom with light.


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