L.e.d.

[imsoborednow]

Zdaravo people,
Im gonna attempt some growing via a DIY Led system.
Ive been reading some threads and its got me going, Just in ma head (makes a change)
My Goal...
Being able to light an area of 1 sq metre growing 4/6 full size plants (I say full size plants, obviously this will be done indoors and covertly, so I reckon on about a 4ft finishing height.
Replicating as close to a 400 w HPS lamp as poss.
I know that I am not trying to replicate the 50 000 lux I get from my Hps,All I gotta do is replicate the specific bands of light usable by the plant,which I fink are as follows

80% red @ 660 nm


10% blue @ 435nm

5% far red @ 740nm

5% uv-b @ 300nm

Ok so far, this gives me percentage.

We can calculate that a 1000 w hps light only delivers 124 watts of energy to the plant (108w direct and 16w indirectly) right. So to estimate the wattage I need:

124 / 10 = 12.4 per 100w, 4 x 12.4 = 49.6 w
So I reckon I need 50 watts of effective lighting from my leds, spread over 1m 2.

right so far?

Power supply to be 12 Vdc.

Just trying to decide what sort of array to make (any ideas?) needs to be on a frame to raise and lower easily,
Obviously all light needs to combine and be spread evenly over the plant surface...mmmmmm.

LEDs Im shopping for now .

Just need to know how many Leds for 1 w of power

[Elephant Man]

I have a link to send to you:cool: , check your mailbox.

[Elephant Man]

Material : Aluminium
Size : W69.5 x H59 x D9.5cm
Emitted Color : Red
LED Q'ty : 900pcs
Voltage : 110v
Power : 110W
Protection Rating : IP20
Luminous Intensity : 7,200,000MCD

[Smoked Out One]

can you pm me the link?

[imsoborednow]

Been Thinkin...it hurts sometimes!...All these led arrays I have seen so far have been flat and directly posioned above the plants, OK, The beam angle of the leds are pretty thin right, we want the colour spectrum to converge , or overlap to give the plant the full spectrum of light being emitted. Has anyone had any experiance with lenses/diffusers to spread the light out a bit?
3M have a reflective film which is 98% efficent.....how effective is mylar? or matt white paint. I found an American company which offers promise see link.....http://www.poc.com/lsd/default.asp?page=custom_oem_products&sub=main
I think that because leds are expensive.when you want a 'good angle' maybe a small efficent lens to spread the light over a larger area would be benifical, if say I manufactured an LED array with a (eg) 15 watts or approx 600/750 led
The array could be made very compact, this would only have a small 'footprint ' of light this I believe needs to be made larger and without getting to far away from the subject.
Maybe?

[imsoborednow]

LSD's (light shaping diffusers not of the acid variety) if made from poly carbonate it should only absorb between 8 & 15% of light compared with 40 to 50% if glass is used.

[imsoborednow]

This one looks good,
http://www.bfioptilas.es/upd/product_upd/file/suppliers/physical_optics_corporation__poc/lsd_uv_transmitting_acrylic_embossed/uv_transmitting.pdf?sid=61fbf0186de4a02497390bf1e4 71ba85
Will try for samples

[imsoborednow]

Ok heres the proto, one bread board using 60, 10mm leds,(55 red/5 blue).which are rated at 60,000 mcd and 30 degrees visable
this draws nearly 3 W

[imsoborednow]

This is the view of the ceiling, I guess about 6ft from the table.

[imsoborednow]

Leds are pulling 2.75 watts.....so......1090 leds = 50 W
thats enough for one night....spliff time......

[imsoborednow]

872 red, 109 blue, 55 far red & 55 uv...

[imsoborednow]

I found a subject thatll do for now.
One 3 week old runt from our last seed start dunno what it is!
into my stealth starter/clone box, nice cooler eh! (normally run with 2 100w home flos.) I have mounted the proto board on wood and suspended the lights 1 ft above. Measured light at plant top with my lux meter and reading 7,000 to 10,000 lux if I move the recepter around in about a 2" circle. we'll see.
Next step.
Have put a bean into the floatation chamber and will start a seperate thread on the total led grow when it cracks.

[Mutt]

Now I am excited. Can't wait to see how this baby works. :D
I have a huge bread board from college all I need is the LEDs. So I am waiting to see how this works. if it works great...There go my flos for veg.
Mega Props man.
You wouldn't mind if I PM'd ya with questions every now and then? I know the electronic part. just not the light configuration requirment.

I moved this over to the DIY section. It fits here to well. :)

[imsoborednow]

No Problemo Mutt, Thx for the interest......

[Elephant Man]

Like Mutt, I am also watching this thread, my biggest battle will be heat in the summer....

[naturalhi]

Why not hang 'em from the plants limbs like a Xmas tree=-D

[imsoborednow]

Purchased 5 no matrix boards 500 x 100,Strip boards costing $10 each, Leds are will be on thier way in a couple of weeks (just haggling final price).! have decided to go for red/blue /green arrays using 1250 leds, 880 red / 220 blue and 100 green, Im arranging these on my boards in 25no blocks as this makes soldering and reference easier , also cos im running this in 12v I can only go 5 parallel @ 2.3v.
I decided to include some green as I understand that although the plants will grow happily under just the red and blue leds but the plants will turn black cos there is no green light to affect the clorophyll , so 100 green will give me 2 on each 25 block, SO each block is made up of 20 red, 3 blue, and 2 green.
Now the soldering.......50 x 25 led blocks, 10 on each matrix board.
Will keep on posting when I receive leds...
Meanwhile . Im starting a complete grow from seed as I have enough led to start , which I will start a seperate post for . :)

[Mutt]

Hey man, quick question. Wouldn't yellow be in there too as well with the red and blue?
Then green would not be needed. Just a thought figured it would get two spectrums from the use of the mix. (yellow/blue=green):confused:
Sorry if this sounds dumb.

[naturalhi]

Hey Mutt, I used to repair 'puters at the lab, that monitor you're looking at uses only red, blue, and green "guns" to produce the 'billions of colors' you see on the screen. intensity of each gun is the key to color.

Imso, Just a thought, if you got equal #'s red, blue, and green install the clusters on the board like they do on those big signs, or led screens. wire all the seperate colors together, and connect to three seperate variable resistors or pots or what have ya. then you could adjust spectrum any where you like, from black to purest white.

[Elephant Man]

7 - 10k lumens from 50 watts, not bad. My battle is heat, so this would be great for me.

[imsoborednow]

I like your thinkin Natural eye, its something to look at......
Been away for a few days , The grow journal starts today so dont forget to check out the thread later........

[naturalhi]

I just read an article in this months Popular Science it said in the future we'll be able to change the color of our walls at home with a switch!

Think about it LEDS in your walls! why not the grow room too!

[imsoborednow]

Sorry Guys Ive been waiting ages for these leds......meanwhile I started to bring on a couple of seeds

[imsoborednow]

They stretch for light I think.......then they seem to stop and grow normal .:confused: The lights are 250mm above the soil the seedling needed to get to 100mm tall before it started sprout real leaves....mmmmmm....ive only got 50 leds in this array maybe its not enough to start growing, we'll see there is no diffuser on these leds though...

[imsoborednow]

Just got a quote back from the British end of POC (for the diffuser see earlier link) . Just a little over the top.....guess they dont like dealing with little people.....below is the quote


Thank you for your enquiry.

The best format would be to offer a 20" square. You'd need to select which substrate and which thickness and indeed which distribution you require.

For example L60P1-20" would be 60 degree performance on polycarbonate 0.010" thick. This product will give 85% or more transmission.

Price for this would be £212.50 +VAT. (£250 or $475)

This price would apply to any of the formats you mention in thin film.

Lead time would be about 3 weeks from our receipt of your order and payment



Thats a hell of alot of money..more than what this project will stetch to.....so
back to the drawing board.....you guys have any ideas???

[naturalhi]

Here's a build 'em yourself link for the LEDs;http://business.search.ebay.com/LEDs_Business-Industrial_W0QQcatrefZC2QQfromZR41QQsacatZ12576

Enjoy!

[EldestChron]

While you're right about the monitors. I'm not so sure that applies the same to using LEDS for light. For the LEDS are manufactured to produce a specific wavelength of light. And aren't meant to be over powered, and wouldn't get the same effect if under powered? and If your underpowering red or blue to get a different colour, then that's kind of a waste. It would probably be wise to include LEDS of all the wavelengths necessary. BTW Yellow around 525 nm triggers photosynthesis in plants...

[Flashback 360]

okay right-off you probably don't need green LEDs.because the plant's chlorophyll cannot absorb the greenlight
the Red Lake helps with the growth of plants and chlorophyll the blue light copes with the direction of the plant. .

[Flashback 360]

the blue light helps with the direction and mixes with the red to make purple that helps flowering . and the light intensity probably shocked the plant since they would be getting 8 times the lluminescent's they would be from wight light .

but the light dissipates over the distance so it is good to keep the led's around one foot from the plant's closer you might experience erratic behavior such as spontaneous flowering

try using reflective insulation in your enclosure