Karl H. Posted March 29, 2013 Report Share Posted March 29, 2013 Hello, today i´ve finished my LED spot light heads. They consist of 20 cree LEDs and one 30W (20W white and 10W UV) LED each. Im currently working on the main driver panel wich is able to power up four single LED spot light heads. The driver panel has an integrated programmable time swich, and three different driver modes. The first mode ist the manuell mode with wich you can deactivate the time switch and switch on or off the LED lights. The second mode dims all LEDs except the 30W withe LED down to 10% of their actuall power, so that you can view the plants with an agreeable colored light. The third mode switchs on the second mode automatically if you open the door of the terrarium for example. so what do you think? I will updeate this Thread when i have finished the driver panel. best regards Karl H. Quote Link to comment Share on other sites More sharing options...
TheInactiveMoth Posted March 29, 2013 Report Share Posted March 29, 2013 Very clever! (I see you have put one of your interests as optoelectronics; it's obvious that you know what you're doing! ) Quote Link to comment Share on other sites More sharing options...
Prompt Posted April 1, 2013 Report Share Posted April 1, 2013 Hello Karl, also I use white LEDs for my ceiling and I must say that the results are very satisfactory. Your work is very well done, I wanted to know the code of the LEDs and if the central LED panel is a warm white or cool white. thanks for sharing your work;) Prompt Quote Link to comment Share on other sites More sharing options...
Karl H. Posted April 1, 2013 Author Report Share Posted April 1, 2013 Hello, thank you for your kind comments.. It´s great to hear that your LED ceiling works good. I use the white LED primarily to cover up some wavelengths which i cant generate with monochromatic LEDs. The 30W white LED has a color temperature of 12000K. I´ve chosen such a high color temperature because LEDs with such a high Kelvin value have a high peak at 450nm blue. (at least GaN and InGaN LEDs) The red LEDs are all Cree XM-L types, ant the orange and blue ones are Cree Q5 XR-E. i hope these Informations were helpful for you. greetings Karl Quote Link to comment Share on other sites More sharing options...
Prompt Posted April 1, 2013 Report Share Posted April 1, 2013 OK Karl, I use the technique of reverse, use LED warm white and cool white 1:1. In my experience in the optoelectronics led warm white are those that best serve the red spectrum, including the far red. While cool white LEDs are used to give an extra boost to the blue hue. I find it interesting the addition of UV LEDs that if I'm not mistaken should help strengthen the extreme range of the blue. In this regard wanted to ask the wavelength of the UV LED in nm ? As soon as I have time I will experience the addition of LEDs to red (730nm), which according to my research should stimulate the phytochrome and boost the the growth and flowering of the plant. My aim is to provide a ceiling that is white light and providing for addition of wavelengths not visible to the human eye. regards Prompt Quote Link to comment Share on other sites More sharing options...
Karl H. Posted April 1, 2013 Author Report Share Posted April 1, 2013 I have the same aim as you, to get a good grow light without an ugly mix of colors. For now this works just fine with the 30 white LED because the big amount of white outshines the rest of the monocromatic light. I also did some experiments with far red, and it seems to work fine. I´m working on a spot light at the moment wich i´m going to combine with my other spot lights. With this combination i can dim every color individually. The wavelengths i cover up are the following: 730nm 660nm 630nm 600nm 520nm 460nm 430nm 380nm regards Karl Quote Link to comment Share on other sites More sharing options...
Prompt Posted April 1, 2013 Report Share Posted April 1, 2013 a few questions: which receptor is sensitive to wavelengths UV and that benefice draws the plant? is the first time you experience the white LEDs? regards Gianni Quote Link to comment Share on other sites More sharing options...
Karl H. Posted April 2, 2013 Author Report Share Posted April 2, 2013 Hello, i don't now which reseptor is sensitive to the uv light. But the planst generate the red color as a uv light protection, so it you give them much uv light they should also get a great red coloration. No i made some experiments with white LEDs before. Regards Karl Quote Link to comment Share on other sites More sharing options...
mobile Posted April 4, 2013 Report Share Posted April 4, 2013 I believe that in the UV spectrum, it is UVB that is most interesting for plant colouration. Other UV wavelengths do not appear to have such an influence: 'The effect also seems to be particularly sensitive to the wavelength used ? peaking at 282 and 296 nanometers, and absent for longer wavelength UV' Read more at http://scienceblog.c...qlHWVZHOxRCm.99 Unfortunately, UVB LEDs do not seem to be readily available. Quote Link to comment Share on other sites More sharing options...
Prompt Posted April 4, 2013 Report Share Posted April 4, 2013 LEDs uvb can be purchased directly from china: http://www.alibaba.com/trade/search?fsb=y&IndexArea=product_en&CatId=&SearchText=led+280nm I buy many components, LED lamps, etc. .. directly from Chinese companies Prompt Quote Link to comment Share on other sites More sharing options...
Prompt Posted April 4, 2013 Report Share Posted April 4, 2013 Another interesting test on 380nm UV light, it seems that this wavelength has had positive effects compared to other tests: http://www.lzi.lt/tomai/97%282%29tomas/97_2_tomas_str10.pdf Prompt Quote Link to comment Share on other sites More sharing options...
mobile Posted April 4, 2013 Report Share Posted April 4, 2013 I have a 400nm UV LED cluster and I can't say that I've noticed anything particularly markable about plants growing under it (in combination with other LEDs). I would be interested in trying a 280nm, but the MOQ or single unit price makes them prohibitively expensive. Quote Link to comment Share on other sites More sharing options...
The body snatcher pod Posted April 4, 2013 Report Share Posted April 4, 2013 I have heard deep blue stimulates red pigmentation as good as UV light does. Quote Link to comment Share on other sites More sharing options...
mobile Posted April 4, 2013 Report Share Posted April 4, 2013 I have heard deep blue stimulates red pigmentation as good as UV light does. Blue light doesn't seem to have much affect on Cephalotus colouration, neither does UVA. Quote Link to comment Share on other sites More sharing options...
Petr Posted April 13, 2013 Report Share Posted April 13, 2013 Very interesting setup. Couldn't be easily used a common light-bulb instead of LED 730 nm? Quote Link to comment Share on other sites More sharing options...
Karl H. Posted April 14, 2013 Author Report Share Posted April 14, 2013 Hello, every object above 0K such as the glow wire in a light bulb emitts thermal radiation. A light bulb however emitts very much thermal radiation, which could heat up the terrarium. (depending on the wattage of the light bulb) A light bulb also doesn´t emit much radiation at 730nm, so the use of a LED is more efficient in this case. I also made some progress with my controll panel, but unfortunately it´s a bit a "quick ´n´ dirty" construction. I´m making the PCB´s right now for the controll panel with the µC, but it could take a while until the "final" controller is completet. regards Karl H. Quote Link to comment Share on other sites More sharing options...
Petr Posted April 19, 2013 Report Share Posted April 19, 2013 Hello, yes probably LED will be more efficienct, but if you use some very small incandescent light bulb it should works... The question is, if are the other wavelengths in infrared spectrum of it usefull for plants... http://www1.union.edu/newmanj/Physics100/Light%20Production/LampSpectra.gif I will try it, thanks for inspiration. :) Quote Link to comment Share on other sites More sharing options...
Karl H. Posted April 21, 2013 Author Report Share Posted April 21, 2013 Hello, i finished my LED Spot light with the quick ´n´ dirty driver panel today. I still have to make some changes on the driver settings, to get a more pleasant light. I also started the 48h burn-in tets today, to see if any component gets too hot. What du you think? regards Karl Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.