Introduction: USB Powered LED Grow Light

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hello world, ( remember to check out new prototype uploads on my profile )

my first instructable over here, so please bare with me. last week i really got into basic electronics/circuit boards and especially LED lights, powering them via usb/battery/solar. this webpage is great for such new knowledge, thank you so much for all..! i believe that LEDs are taking over as the source of our lighting needs, they run on barely any power, very cheap to manufacture and are very easy to work with. they are uncomparably brighter and more efficient.


PLEASE NOTE: this was a quick afternoon, testing my newly learned skills type of project. LEDs used in this project are not the right type for plant life. assume this as my "USB powered LED plant light Version 1.0" because i'm already learning about how to make this baby run on solar and battery, with on/off switch and also adding the right spectrum LEDs (parts are on the way)... correct plant light information can be found on; (you need to get familiar with spectrums - 430nm/blue and 662nm/red) , and all the parts you need are on eBay, from china with love, practically free


let's start with the parts needed as step 1 ;

--- IMPORTANT: Everybody please make sure you have read at least introduction to electronics. Know your resistors and know the Ohm's law (use a calculator to be safe: ) - Look at many other designs, get familiar with what you want to do, SKETCH IT first, always be extra prepared and have fun !

Step 1: Parts

1. any USB cable you can spare (under $1 - local thrift store)

2. perforated metal pipe hanger (usually $2.50 for a roll - enough for 2 projects - local hardware store)

3. plant in pot (use plastic pot, so you can screw into it easily)

4. LEDs (any number, i used 6 - this is a complicated step that requires basic electronics knowledge, it will be discussed in depth later on...)

5. you also need to understand the fact that electronics do not prefer gender/race or religion. we are all equal, loving earthbeings. this instructable is purely for the free wisdom of mankind, for someone else to view it and take it to the next step. please be kind when commenting. :)

6. - you actually also need 2 screws, to secure the metal hanger to the pot, you can use a bolt and nut too if there is no plant in pot yet.

!!! stock images are taken from Google Images search results !!!

Step 2: Secure the Hanger

1. hold your metal hanger against the plant pot with one hand and start unrolling with other hand until desired height is reached.

2. once you reach the desired, question mark style shape simply bend the metal hanger over the top and follow down your original first layer down the path until you reach to the bottom of the plant pot where you first started. doing this will give you equal length of same sized metal hanger, without cutting.

3. to cut you can use heavy duty scissors, or if you simply bend the metal hanger front and back several time at the same spot, it will eventually just snap off very clean and straight - usually doing it about 30 times is plenty.

4. if you are careful, your wholes in your metal hanger will line up perfectly, so you can go through both layers leaving your self with a much more stable hanger.

next step is securing LEDs...

!!! stock images are taken from Google Images search results !!!

Step 3: Secure the LEDs

now that your hanger is secured safely you can start doing the same with your LEDs.

again, the right types of LEDs and how to connect them in series/parallel are a whole another story and you need to learn on your own, please visit;

1. LEDs for Beginners;

2. Basic Electronics;

assuming you read both and watched some cool youtube videos, you should be upto speed. otherwise i can't be held responsible for any damage, overloading USBs can be dangerous. always make sure to apply the right amount and strength resistors to any circuit. you have to read both of those articles before attempting the rest of the experiment.


for my wiring diagram i used 6 standard 3mm LEDs - bluish/white color. i wired 2 sets of -- 3 series connected LEDs -- in parallel. so in theory the USB power source thinks I have 2 LEDs connected only, each of them equaling to the same power of 3 LEDs put together. 3rd picture should give you some idea of the wiring done, in the picture there are 2 sets of 4 LEDs, mine is 2 sets of 3 LEDs... again this is a very basic explanation. (this picture is taken from the video; - you should watch this video as another source as well ).


i used hot glue gun to secure the LEDs to the frame, one thing that you should be very careful about here is to make sure that NONE OF THE ELECTRICAL WIRING SHOULD TOUCH THE METAL FRAME. this may result in serious injury, fire, sparks, your computer burning... you get the idea. use plenty of glue so the legs of the LEDs are no where near the metal frame, we will be covering everything with electrical tape later on anyways to add more security.

Step 4: USB Connection and Soldering

ok now, after we placed all the parts on the wire, we still have to solder them to the usb.

1. start by soldering the LEDs together first in the order you've decided on (series + parallel) . after this is done, you should have left with a black ( - negative ) and a red ( + positive ) wire hanging out.

2. now cut your usb cable, revealing the inner cables. get rid of any other color except the red and black, these are your power source cables, matching with your LED cables. solder the matching color cables together.

3. now it's time to test, please make sure you have double, if not triple check your work, calculations regarding resistors and LED input/output. if everything comes on when you plug in the USB, you are done go ahead to step 4, if not check everything once again, read more on electronics, ask me or other users questions.

4. securely tape everything together, make sure to use electrical tape, preferably white, i used black so the rawness of the electrical components are very visible. white tape should hide everything with a similar color background, looking like nothing is there.

have fun, possibilities are endless. like i've said, i'm already putting together a new version with real lights, solar energy, switches and batteries.... see you soon..!

GROW PLANTS ANYWHERE, ANYTIME - turn those dark windowless office spaces, or apartment buildings into a place of life and light.

!!! stock images are taken from Google Images search results !!!

Green Electronics Challenge

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Gardening & Homesteading Contest

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Gardening & Homesteading Contest

Gadget Hacking and Accessories Contest

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Gadget Hacking and Accessories Contest