GreenPassion.org - Dedicated to Medicinal Cannabis Cultivation and Education - Growing With LED

LED Light Build Log - In Pre-Production

Shpongled — Mon, 16 Nov 2009 04:04:22 GMT

I am NOT an electronics expert. If you see errors in my posts please correct me so they can be fixed.

As some of you know I am working on designing a small LED grow light. This is purely a hobby interest for me and I am not looking to sell a product. Because of this any info I find or learn will end up right here for anyone that's interested. Currently I am in the research phase and I will document the progress in the first post of this thread. I will be using the second post for my appenidx. Any interesting websites, component sources and otherwise useful info will be there.

Enjoy!

11/15/09
My research is starting to pay off. I have finally found some high power LED's in the 660nm range (Dark Red). There seems to be a growing number of producers of LED's for the horticultural industry.

One such product is the LEDEngin 660nm Deep Red LED.

Press Release: LEDEngin 660nm LED

Mouser - LEDEngin 660nm RED LED:
5W ($11.70):LZ1-10R205 LedEngin LED High Power (> 0.5 W)
10W ($32.50):LZ4-40R210 LedEngin LED High Power (> 0.5 W)

Along with the Red 660nm spectrum range the Blue 453nm range is also important. LEDEngin also has 5W and 10W emitters that are close.

Mouser - LEDEngin 465nm BLUE LED:
5W ($9.90): LZ1-10B205 LedEngin LED High Power (> 0.5 W)
10W ($32.00):LZ4-20B210 LedEngin LED High Power (> 0.5 W)

Here is a link to all of the high power LED's from LEDEngin: LedEngin LED High Power (> 0.5 W)

To fill out the spectrum I will probably add few more colored LEDs but I will also be adding some Warm and possibly Cool White LED's.

This following site has some great prices on Luxeon 1W and 3W Warm White LED's. Currently they are selling the 1W for $3.50 and the 3W is $4.90. This is roughly half the price of elsewhere.

Luxeon 3300K Warm White LED:
Specs: PDF
Purchase: Luxeon LED

There are multiple ways to drive these LED's. You can use a simple resistor for each string of multiple LED's or use a LED Driver which will operate at a higher efficiency (90%+).
You can find drivers that operate off of either AC or DC inputs so you can find one that's right for your application.

This site sells many different LED drivers: LED Drivers - Constant Current Drivers - LuxDrive - LED Supply.com

You want to match the output current (mA)of the driver to match that of the LED's. For example the Luxeon 1W LED's have run at 350mA so you will need a driver that outputs the same value. Along with that the total output voltage limits the total number of LED's.

I am will be running my LED's in series which meas they are all connected to each other and the first and last LED is connected to the power supply.

Here is an illustration:

The image about is an example of LED's in series using a resistor to regulate the input current. The resistor is not necessary when using a LED Driver.

When LED's are in series the forward voltage(Vf) is cumulative for each LED. If the Vf of these LED's is 3.5V the total Vf for this series would be 10.5V. The current draw in a series is the same across the whole series. So if each LED draws 350mA the draw for the whole series would still only be 350mA.

NOTE: In my examples all of the LED's in the series are of the same type. I don't know what should be done if you are mixing and matching different LEDs with different forward voltage or current.

Time for another example:

Lets say I am using BuckPuck 350mA DC LED driver powered by a regulated 24V DC power supply. The BuckPuck has to have an input voltage that is at least 2V higher then the total Vf used by the LED's. That would mean the total voltage available to my LED's would be 22V.

You now need to look at your spec sheet for the Forward Voltage of the LED's you are using. The forward voltage(Vf) listed on the spec sheet is the average value so this could be a little different on each LED. You can test the LED's with a multimeter to see the actual voltage drop or just go by the spec sheet. If you are running multiple LED's on each driver this is not as big of an issue. The differences of each LED should even out.

Now lets say the forward voltage(Vf) of each LED is 3.5V. Remember my driver can provide a max of 21V.

This would mean I could power 6 LED's from each driver:
3.5V+3.5V+3.5V+3.5V+3.5V+3.5V=21V

In theory this is perfect but because of the differences in the forward voltage of LED's its a little tight. A small difference in the actual numbers could cause me to overstress my driver. Remember to keep that in mind, a little headroom is always a good thing.

To continue this lesson, if you are using a DC LED driver you will also need a AC - DC REGULATED power supply.

Power supply: 24VDC @ 4.2A POWER SUPPLY

So now we know that each 350mA BuckPuck driver can power up to 6 of my chosen LED's but how many BuckPucks can the power supply support?

Remember that when running LED's in series the same current flows through all of them. In this example the LED's will draw 350mA.

Each string will use 350mA (.35A) and the power supply can provide up to 4.2A.

4.2/.35 = 12.

I can run 12 series of 6 LEDs for a total of 72 LED's off of the power supply.

Each series will require its own driver but all 12 drivers can be powered by the one 24V 4.2A power supply.
11/16/09

I have been in contact with two LED suppliers today and am making progress.

First up is AOPLed.com
They are a US based manufacturer of high power LEDs. The have a few that they specifically marked for the horticulture industry.

The two 660nm LED's they produce are:
PU-1WRE 1W 660nm LED: AOPLed.com 1 Watt High Power 660nm True Red LED Lamp, 350mA, High Temperature, High Driving
L-995PUSRC: http://www.greenpassion.org/attachme...1&d=1258417577

I was told they both emit 6-8lm which is a bit disappointing compared to LEDEngin. The only place I can find them is directly from aopled. You will need to email them to order.

The pricing I received was:
L-995PUSRC - $1.65 (no min)
PU-1WRE - $2.80(min 100)

I am getting 5 of the L-995PUSRC next week for testing. I will snap some pics when I have them connected.

I also have been in contact with Roithner-Laser. They are based in Austria and have a decent selection of LED's. You can see their full list of high power LED's here: high power LED, led array, white power LED, power chip led, 350 nm LED, 370 nm LED, 380 nm LED, infrared power LED, power LED illuminator, TO-66 LED, LED current driver, LED heat sink, LED cooling fan

I am waiting on prices.

I hope some of you find this post useful. I will be updating it regularly as I source more parts, design the circuit and build my prototypes.

Please feel free to add any info or parts that you find! I am finding it tough to source good LED's so any help is appreciated.

All calculations are for the specific values in my examples. Make sure to use the correct values for the components you are using.

Attached Files

L995PUSRC (V1.1).pdf (211.9 KB)

LEDS...really?

NoBsplz — Sun, 15 Nov 2009 18:08:03 GMT

I know I'm new here, but I just cant help but try to drum up a little debate.I've been checking in here from time to time, as well as a few other sites, researching this current led "boom".I run a cool tubed 400 watt hps in a 4x4 grow tent, and I was considering delving into the led thing.Who wouldnt want to achieve hid results at a fraction of the wattage?Enter the 90 watt ufo...400-600 watt hps equivalent, runs cool, blah-blah-blah.Well, no one has substantiated that claim.Now we have double ufo's- theres a 180 watt ufo now right? Supposedly equal to 400-600 watts of hps...then what is 90 watts equal to?Now we're seeing hps vs hid comparison grow journals...with the wattage being equal on both sides....huh? Now, I've seen some so-so results with these things...but nothing that compares to ANY led salesmans claims.And at these ridiculously infllated prices?What if someone sold you a car that supposedly topped out at 140 mph, and when you drove it, it couldnt crack 40 mph?I'd be furious, and thats exactly the reason that I wont purchase any led unit at this point and time.Now these are my personal observations...I'm not saying I'm right.And I would love to be proved wrong, with believable data from an unbiased source...of course.But I just harvested a plant that gave me 150 grams, and 4 more behind her about 5 weeks away.I would even be interested if led, and hps we're equal watt for watt... but nobody has proven that yet, as far as I know.Can anyone shed some light on this.Once again, I'm not here to start a flame war.I'm obviously interested...I just cant find proof that this is a viable-equal producing-alternative to our hid love-hate relationship.Heres my box o buds, to show that I do grow

Attached Images

	box o buds 005.JPG (119.8 KB)
	box o buds 004.JPG (146.9 KB)
	box o buds 007.JPG (210.1 KB)
	box o buds 006.JPG (286.4 KB)

GrowPanel 45?????

rushchaser — Fri, 13 Nov 2009 04:08:39 GMT

I wanted to know if anyone has had any luck with the growpanel 45 in a small cab. Or if there are any recommendations for a led panel for a small cab. 2'x2'x4'.shakehands.gif

LED grow panel 600 watt

alldayeducation — Wed, 11 Nov 2009 03:07:11 GMT

This guy tells me that he can yeild 800 + gs with this 600 watt led thats compared to 12-1400 hps ..does any1 esle belive this, cuz im thinkin about buying one of these led panels but there 1900$ for one 600 led unit, so im tring to get as much info as i can...this guy sells them at this site he says he makes the best ones that you can buy any where in the world, he said hes been trina to figure out the right formula for like 5 yrs and said that hes happy with his studdies and now selling them to public... heres his site.. Welcome to Grow LED Hydro - LED Grow Lights - Hydroponics - Plant Lighting and video

LEDs and Wien's Displacement Law

JBeezy87 — Thu, 05 Nov 2009 22:29:15 GMT

Question about these lights I found. They are 1.5W LED bulbs with a 6500K temperature rating. About 8 dollars and carried in the hardware shop down the street, I would love it if these lights actually did something useful for my plants. So I did a little reading on the relation of Color Temperature and the wavelength of emitted light. Found Wien's Displacement Law (wikipedia):

λ = ≈3,000,000 nmK/T

where λ is the wavelength of peak intensity, and T is the color temperature the black body in Kelvin.

A little more reading on other sites (sources below for verification) indicated that this law holds true for solid state lighting, and, therefore, LEDs.

Working this equation through (using the more accurate 2,897,769 instead of 3 million) with 6500K, leads to a wavelength of 445nm. Since LEDs emit only select wavelengths, I assume that this bulb would only emit 445nm light (or right around there).

And since 445nm light is great for plants in vegging, I think these lights would provide great supplement lighting.

Any comments on my reasoning? Or has anyone tried these out before?

Thanks.

Souces:
SOLID STATE LIGHTING DEVICES AND METHODS OF MANUFACTURING THE SAME - Patent application
"This occurs because the wavelength associated with the peak radiation of the blackbody radiator becomes progressively shorter with increased temperature, consistent with the Wien Displacement Law. Illuminants which produce light which is on or near the blackbody locus can thus be described in terms of their color temperature."

LED Light Knowledge - Suzhou Neopower Electronic Co., Ltd.
Under a section titled "Technical Parameters for LED Light":
"Color temperature is a characteristic of visible light that has important applications in lighting, photography, videography, publishing, and other fields. The color temperature of a light sources is determined by comparing its chromaticity with that of an ideal black-body radiator. The temperature, usually measured in kelvins(K) at which the heated black-body radiator matches the color of the light source is that source's color temperature, for a black body source, it is directly related to Planck's law and Wien's displacement law."

LED*Waves LED Blog: Doctor, my color has a temperature!
"The future of video and still photography undoubtedly belongs to digital equipment with solid-state lighting (LEDs and OLEDs). This allows for precise control of color temperature and uses a fraction of the power of regular instruments."

Attached Images

	Ledfull.jpg (28.3 KB)
	Ledzoom.JPG (105.6 KB)

First Grow, want to use LED's. Need some help

closetedgrower — Tue, 03 Nov 2009 03:50:04 GMT

I am attempting my first grow and would like some info on LED's

I will be growing in my closet and i wanted to ask about what i will need.

I wanted to devide it into 2 and have one area for veg growth and one area for flowering. What LED's are good for which? i thought that it all depended on the cycles i give the plants (18/6 for veg and 12/12 for flower). If this remains true, could i use the same LED for both of these? I wanted to buy this light :

BRAND NEW Tri-Band 90 Watt LED Grow Light UFO

AKA 4th Generation - Best Spectrums!

Optimum Wavelength (70 Red 660nm : 10 Blue 460nm : 10 White 6,000 Kelvin)

Equivalent to 300 - 400 HPS / MH Grow lights

We use only the highest quality BridgeLux LED's and SemiLEDs chipsets - Each LED outputs 1 Watt! Most importantly, our LED Grow light have the most efficient spectrums in the market - 660nm Red and 460nm Blue are the exact spectrums necessary for the best result of photosynthesis. Additionally, our Warm White LED's provide powerful wavelength (6,000 Kelvin) to cover any missing spectrums! Your plants will fully absorb the wavelengths for photosynthesis. Our LED Grow lights are the finest units available today, utilizing every bit of energy and providing optimal results!
Days of large bulky ballasts, cooling and expensive electricity bills are over! Each unit is equipped with three intercooling fans to keep the units from overheating. Our units will never overheat, therefore never scorch or damage your precious plants. Larger MH / HPS lights require cooling systems, ducting and heat exhaust fans. Now you get everything in one simple package!
If you've done your research, you know that the combination of Red and Blue LED's are the most effective settings - The Powerful 6,000 Kelvin Warm White LED's will cover any missing spectrums! Other models offer poor wavelength settings that are not the exact 660nm Red and 460nm Blue peaks absorbable by plants. Photosynthesis is achieved at these exact color spectrums, and our model offers the optimum wavelengths for the best results. You can find NASA study results regarding these spectrums online, which reference these exact specifications!

Is this an alright investment, they seem to use some high quality LED's. Or is this just good for a certain period of growing? I am open to suggestions, but i thought that LED's would be great for a closet that would pretty much be closed off and the fact that they do not release much heat would keep my plants safe. The closet is 3.5ft x 1 5/6 ft., so i was expecting to grow like 3 plants in the flowering section of this.

So, the main question i have is, can i use this tri band LED for both flowering and veg growing?

Very much appreciate your input on this !

Color selection for LED grow setup

The HSIC — Thu, 29 Oct 2009 01:30:42 GMT

Im setting someone up a closet and i was going to try adding LED floods to the flower "room" in addition to CFLage. Wich colors are good to go with? ive done some looking and it looks like red and blue maybe......

but im not sure.....

ive grown indoors before so im just looking for some input from someone else who has thanks alot