Comments on: Finnish Windowfarms Team Adds LED light component

By: he1ios

he1ios — Wed, 08 Sep 2010 06:25:09 +0000

Sorry for he delay Mr. Whippy.
here:
http://www.hebeiltd.com.cn/?p=zz.led.resistor.calculator#series
this is a company that sells LEDS and even more useful is their LED resistor calculator.

You should get a bunch of LEDS and add the milliamps of each one. tack on another 20% for buffer and that is the amp rating of the power supply you should use. But if you find a power supply that gives more than what you really need then just go for it. Just make sure the supply gives at least your requirements. Its very likely you’ll find one of those wall wart type supplys at a thrift store or rummage sale. I’d look for one that puts out 12V DC at whichever current ( milliamps ) you need.
Use the calculator on that website to calculate the resistor needed and solder it in line with the positive supply side. Thje negative from the power supply goes, of course, to the negative side of the LED series which are wired together. Negative to positive and so on. Heck there are tons of iinstructional videos on Youtube that show how to do it. Here’s one I really liked because he has a cheap and easy way of holding the leds.
http://www.youtube.com/watch?v=mpzNg8FF0RE&NR=1
Also in the comments this the guy suggests to only gang three leds in series at a time although I’ve done as many as eight while using one resistor .
I’ll post a step by step if I get some free time.

By: kroner78

kroner78 — Tue, 10 Aug 2010 07:58:56 +0000

I’m just about to move into a flat which faces North so I’m looking into LED growlights for my windowdfarms but I’m an idiot with eloctrickery. I have a soldering iron (never used- and have no solder) and I’m quite good with my hands but I need some advice on linking the LEDs together… I’m also considering hacking a solar shed light so that I can dangle the wires out of the window and sboost the sun’s power using more of the sun’s power… is this too ambitious? It’s got to be easier than wiring it into the mains or a battery pack hasn’t it?

By: he1ios

he1ios — Mon, 09 Aug 2010 06:09:28 +0000

I used pure white 3watt LED strips and it works awsome as a sole light source. Optimum wavelengths like 660nm and 425nm are great but you dont have to be so exact. Just try to find Leds in the neighborhood. My LED strip is made for cove lighting and is super expensive but I had it laying around the house. The cheap way is to find a cheap led supplier , ( just do a search), and solder LEDs together. Its not really that hard; Wire each led in series and solder the proper resistor for each LED. there’s a formula to calculate the proper resistor needed and when I get a few minutes I’ll put together some step-by-step instructions , a formula for calculating resistor values, ( simple math ), and soldering.

By: erku

erku — Tue, 25 May 2010 20:22:25 +0000

mouser has several SMD (surface mount) LEDs in the 660nm and 428nm ranges, which should be good for grow lights. These are very small and would probably need to be purchased and applied in large quantities to be effective. I’m thinking of setting them into a long tube, maybe a slit piece of pvc pipe, and running them vertically next to my plants. Still designing though, long way from building.

By: owen

owen — Fri, 16 Apr 2010 19:02:08 +0000

mouser.com is a good place. They are a very large electronics supplier. The spectrum you want is 660nm (red) and as close to 425nm (blue) as you can find. The per-fab lights for hordo that I’ve seen, didn’t actually have the ideal spectrum. I don’t think a 425nm LED is made, and some hordo lights have something like a 620nm red (probably because they look brighter to humans)

By: jennaspevack

jennaspevack — Fri, 16 Apr 2010 13:49:24 +0000

Anyone know of any places to get grow spectrum LEDs in bulk? So far I’ve only found Sunshine Systems, which sells pre-made panels for much $$$.
Thanks.

By: owen

owen — Wed, 07 Apr 2010 21:46:43 +0000

Sweet, anyone know any info on the LED’s used?
It seems like a 425nm spectrum LED is not made, but that may have changed.
Any updates as to how the LED’s are working would be of great interest.

By: Reading Lights

Reading Lights — Tue, 02 Mar 2010 10:48:59 +0000

LED is the new ink used by contemporary artists, and window designers definitely fall into this category, their dedication to producing something beautiful and functional is impressive.