I know there are a lot of LED light Tutorials, but some of them use pretty interesting power sources, are unreliable, can't be dimmed, etc. I'd like to try to re-pay the group by submitting my LED light scheme for you to try and use. I include a list of everything you need an where to get it.
First of all, What does it look like?
You can obviously use as many Blue/White/Red LED's as you want to get whatever effect you're going for. For instance, this is 4x10k 2x455nm 2x660nm (50% white, 25% blue, 25% red) Blue and red make the purple look... If you don't like the color, or if you have a coral tank, don't use the RED lights. You can simply buy only white and blue.
For your FAQ's -
Q: How much is it?
A: I purchased 295-300$ worth to build 5 x 24W lights. That's quite a but of light if you ask me.. 24W of this LED light lights up my 25gal tank pretty well (Picture above). I imagine that the 5 of them will run light the 210Gal.
Each one after the first costs only ~50$
10$ power supply for each 3 you want to use.
Q: How hard is it?
A: If you can solder and have basic wiring tools then this is not a difficult project at all. The wiring schematic is very simple and the number of wires is low. I built my first one in just about an hour but I'm an electronics geek, so... Leave some time for messing about...
I bought everything off of two websites, www.Ebay.com
Tools you will need to have (or buy):
Soldering Iron (and Solder) - If you can't solder this will get hard because the wires will be really hard to keep in place...
You could need a multimeter (or something) to determine polarity of the power supply so you don't blow everything up by hooking it up backwards.
Shrink tube or electrical tape (for covering the power wires)
Basic tools (Small phillips Screwdriver, wire stripper, wire cutters)
You will need to buy:
1) LED's (3W LED's, decide if you want any RED or not, Freshwater probably wants some Red, Marine/Coral probably not.)
2) Heatsink (I got 5 that are 12" by 3", 8x 3W LED's can fit on each)
3) Thermal Glue
4) Generic 2 part epoxy (plastic+Metal) from Home Depot or Lowes or something
5a) Transistors for Power source (PNP transistors 2A+ @ 20+ volts)
5b) Transistors for Power source (NPN transistors 2A+ @ 20+ volts)
6) 1K0 and 1R0 --> 1/2W or preferably 1W resistors
7) AC/DC converter (15V laptop power supply - make sure its high enough wattage - I use 60W power supplies (4Amps) )
8) Misc adapters to plug the Converter into your light setup - can use anything you want, but I have my suggestion below.
9) Wire (Can get it lots of places, be sure its stranded, I use 20ga)
10) Optional fan
11) Optional dimming control (Simple 100 ohm potentiometer in the current source)
LINKS to what I SUGGEST (and) WHAT I BOUGHT are at the BOTTOM...
Lets get started. The easy bit is to grab all the stuff you have and situate the LED's on the heatsink. I put them in two pretty equally spaced groups of 4, because 15V is only enough to run 4 LED's in series. Thus each group of 4 will need their own power circuit.
Note: You can find larger power supplies that give more voltage but there aren't too many high wattage 30V+ DC power supplies, and since they are special, they get expensive and become a larger part of the total cost which I'd rather spend on LED's. If you find one, let me know and I can show you how to wire it up differently.
Thus your setup will end up looking something like this picture below:
Steps to completion:
1) Arrange LED's and Transistors as shown below: I have already bent some of the leads like I suggest below in step 3 and 7 because I didn't get a good picture. You can attempt to mimic what I have done, or you can leave the leads long and cut/bend them when I say to in the steps.
2) Glue LED's to heatsink using Thermal Epoxy -
2a) Put a little dallop of thermal paste in the middle of the back of the LED as shown in picture below:
2b) Push the LED onto the heatsink and turn it back and forth in place like your screwing it in to distribute the paste. Just a little bit should squeeze out if you put the right amount on.
2c) Be sure to align the LED's so that the (-) of one is pointed at the (+) of the next one in line and the wiring will make a sideways U shape, otherwise it will be less attractive to wire up later. The two towards the center of the heatsink should then be pointing in opposite directions.
3) Take the required 4 transistors, find their fronts (which have faint writing on them), and glue their backs to the heatsink similarly as in step 2.
3a) Place the two transistors on the heatsink similarly approximately as shown in the picture.
3b) If you're not too familiar with soldering, or you are afraid about how small these things are, you can bend the two outer leads of the transistor away from each other to give you space, or bend them towards each other to remove the need to place a wire in-between as shown below. Just be sure to keep them away from the heat-sink so they don't touch.
4) Glue on the female power connector to the heatsink as shown using any type of glue you want (but don't waste the thermal grease on it) cheap 2part epoxy from home depot will work (Picture 3) or attach in any other fashion you wish...
5) Wait for the glue in parts 4 part 2 to dry (it takes like 12 hours or so), just come back another day...
I say to actually wait for it to dry for three reasons.
5.1) While its wet it will come off easily you will have to redo it to get it to attach properly after its half dried.
5.2) Its easier to solder when everything doesn't move.
5.3) It'll save your parts from being overheated as easily by the soldering iron because they will be properly heatsink'd. Its not hard to ruin a transistor by overheating it if your not paying attention and it sucks to unsolder everything and put a new one in.
If you think your really bad at soldering then make a test LED off of the heatsink first and see if it works. The current source (Transistors) will power anywhere from 1 to 4 LED's without an issue so don't bother setting up all 4. They will technically power more, but the Laptop power supply doesn't have enough voltage.
6) Get ready to solder!
6a) Cut the wire into pieces that are the approximate lengths you will need, hold them up to your setup and cut these lengths. Use the picture circuit diagram picture below for reference.
Really short ones from transistor to transistor.
Medium ones between all the individual LED's
Medium ones from the Transistors to the First LED in each group.
Really Long ones to the power plug.
6b) When you strip the wires, you don't need to strip very much at all except for the ones that will go into the power connector (they are screwdown style, so you need room.) See Picture for reference how much to strip, its not crutial. Just a reference.
7) Now that you have a bunch of wires all hanging out you'd like to attach them right? Well a picture is worth a thousand words, so i attached one below. You can click the link for a bigger version, but I posted the largest version I could. Transistors are labeled "E C B" because the pins are called Emitter, Collector, and Base. I will refer to the pins when I say what to connect together. Instructions below the picture.
For larger picture click here...
7.1) Solder up the 3 wires that go from LED to another LED as shown, (+) of one to (-) of the next. Leaving one (+) and one (-) in each group unhooked and pointed towards the center.
7.2) Solder a wire between the remaining (+) of the Right side LED group to the "C" pin on the right PNP Transistor
7.3) Bend the Left PNP transistor "B" pin and the Right PNP Transistor "E" pin together and solder them together.
7.4) Bend the "B" pins of the two NPN transistor together.
7.5) Bend the "C" pin of the left NPN transistor to touch the two "B" pins.
7.6) Solder a wire from remaining (-) of the right side LED group to the 3 pins "B B C" on the NPN Transistors, be sure the solder gets all the pins, the wire doesn't have to touch them all, just the solder.
7.7)Solder a long power wire to the unwired (+) on left side group of LED's (Leave the end with the long stripped end free)
7.8)Solder a long power wire to the "E" pin on the Left PNP transistor (Leave the end with the long stripped end free)
7.9)Twist the power wires together at the long stripped end and put them in the + power plug and screw them down. (You probably have to unscrew it first though...)
7.10)Take the 1-Ohm resistor and cut the ends so that they will connect to the "E" pins on both the PNP transistors.
7.11)Solder the resistor to the two PNP transistors, soldering the side that just has the two transistor pins first, it will make it easier to hold the wire in place on the left PNP "E" pin if the resistor is already soldered on one side.
7.12)Solder a long Ground wire to the Right NPN transistor "E" pin. (Leave the end with the long stripped end free)
7.13)Solder a long Ground wire to the Left NPN transistor "E" pin. (Leave the end with the long stripped end free)
7.14)Twist the power wires together at the long stripped end and put them in the (-) power plug and screw them down. (You probably have to unscrew it first...)
7.15)Cut the 1k ohm resistor so that it can reach the "C" pin of the Left PNP transistor and the "E" pin of the right NPN transistor.
7.16)Solder the resistor in place, try to route the resistor so that the bare wire doesnt touch anything other than the 1ohm resistor body (Its not conductive). If you are worried about the leads touching the heat sink, you can place a piece of tape under it.
Now comes the hardest part so far, there are two wires left and they will be the most awkward to solder. You can probably see them in the picture, and are wondering, why am I not putting them in yet... Well anyway.
Step 8.1) Take either a small length wire or I used a piece of the resistor lead that you cut off. Solder it between the Empty right hand PNP transistor "B" pin and the Left hand PNP transistor "C" pin. Using a piece of leftover resistor lead does not make it easier, it just saves wire. It also only works if you have a piece of the lead laying around long enough... You must make sure that the wire wont touch anything else metal though, so be careful if you don't use covered wire.
Step 8.2) This step is actually optional, but it makes the system work marginally better (equal brightness) and provides a safeguard. So I suggest it.
Solder another small piece of wire between the two "E" pins of the NPN transistors. This will connect the two grounds should one get screwed up somehow. It prevents unknown behavior from the current source should one ground fail.
Step 9: Wiring up the power source. This is the easy part.
Cut the end off the laptop power supply and strip back the black coating. You will see two wires, one red and one white. The red one is (+) and the white one is (-). If you don't see red and white, then you will have to test them with a multimeter or some other tester to tell which is which. All you do is solder some extra wire onto the power source and hook it up to the male power plugs you bought.
Step 10: Plug it in!
Step 11: If there is not adequate airflow above your tank from a ceiling fan or other cooling fans you will need to add a fan to your heatsink. I did, because my light is in a closed box almost...
I have the 80mm fan simply glued on top of my heat sink right in the middle using some of the regular epoxy. Just cut the power wires, strip them and plug them into the power plug where the lights are. The 15V will make the fan run quick, so it'll get loud and it'll kill the fan early. Cut the power wires to the fan again and put a 1W 30ohm resistor in both of the power wires so it doesn't blow up and so its not so loud... This works great to quiet the fan and make it last longer.
Step 1: Take a completed LED light array from above and unsolder the 1 ohm resistor from the PNP transistors.
Step 2: Solder a wire to either side of where the 1 ohm resistor used to be. I.E. one wire to the left PNP's "E" pin and another wire to the Right PNP's "E" pin. Note: the two PNP transistors should still be connected in the middle from "B" to "E"
Step 3: Looking at the potentiometer, it has 3 pins. If you number them in order from left to right, they would be 1,2,3.
Solder one wire to position #1 (on the left pin)
Step 4: Solder the other wire to the 1 Ohm resistor
Step 5: Solder the other side of the 1 Ohm resistor to pin #3 (To the right pin)
Step 6: Solder a wire from Pin #3 to Pin #2 (Use the picture below to verify)
You will notice that there are 2 resistors instead of the single 1Ohm resistor in my picture. This is because I have leveled the light output to equal exactly 600ma. The dimming circuit adds some resistance so I needed to lower the resistor value to 0R8 (0.8 Ohms). I did that by tacking on a piggyback 5ohm resistor. You can do this if you wish, or you can deal with the slightly reduced output.
Step 7: Hang the potentiometer somewhere easy to access. If you want you can glue it to the heat sink, but put something in between its metal case and the heat sink to prevent shorting. I.E. you can glue a napkin or piece of plastic or paper in between them.
Turn it all back on and play!
If the dial "turns the wrong way" you can move the wire that goes from #2 to pin #3. So then it would go from #2 to #1.
- Please comment on things that are incomprehensible... I'm sure there's something in there.
One the first line I tell you what it is, then what I searched for to find it, so if the link ever goes out you can still have a chance to find the object.
Example, For the BLUE LED I searched for "3W 455nm LED" and came up with the 10pack of royal blue plant grow lights
1) BLUE- 3W 455nm LED
If you don't like the cheap items that I purchased, for instance, these LED's. You're free to buy Cree-XPE's from mouser, they'll work just as well in the exact same arrangement.
WHITE- 3W 10000K LED
RED - 3W 660nm LED
2)Aluminium Heatsink for LED
3)Thermally Conductive Adhesive
9$ medium tube (it's a lot)
4) Home Depot or Lowes 2 part epoxy for attaching the power plug to the heat sink.
5a) mje17 epitaxial Note:
Epitaxial packaging (plastic all around to prevent accidental shorts)
27cents each, you will need 2 of these for each 8 LED's. so that's 6 of them for 24 LED's and so on... I'd buy some extra in case you screw up too, their so cheap there's no reason not to... The difference between 170,171,172 is voltage capability, but they are all much higher than were using, so don't bother, just get the cheap one.
5b) mje18 epitaxial Note:
Epitaxial packaging (plastic all around to prevent accidental shorts)
Same as above...
6) 1w 1ohm resistor (and) 1/2w 1k resistor (Search on ebay and you will find some at the very top... Don't bother buying expensive ones, they don't matter.)
1$ for a pack of 10 or 20...
7) 15V laptop power supply
8) 5.5 x 2.1mm
1$ each - need one per heatsink
(Above item AND 1 of EITHER below)
Haven't used this below, so I cant vouch, but it should work and it would be easier to work with. Be sure you have a multimeter, because the wires don't look labeled.
1$ each - need one per heatsink
9) 20ga wire - Note: I'd buy this at an electronics store like fry's or radio shack because its really hard to determine quality on the internet, its really easy to tell how easy its going to be to work with when you touch it... But if you have to buy it online, try this stuff...
5feet for 3.50$, probably should get 2 orders...
10) 80mm fan
Also, in case its too loud for you, you can get these resistors to quiet it down, you could use 1 or 2 resistors per fan.
11) 100 ohm potentiometer
Found this 4 pack on ebay and bought it and they work fine.