I was taking pictures on how to wire a case fan (DC) to an AC wall plug for another member and figured I would just make a post for everyone to see. This is good for getting air circulation inside of a humid terrarium which is great for plants, or for placing at the end of a light fixture to cool it down. If using inside a terrarium with animals be sure to glue screen on the front and back of the fan so the animals can't get the the fan blades and injure themselves.
Case fan from CPU store, ebay etc.
110V AC/DC converter, I prefer the variable output ones so you can select how fast the fan spins. Make sure this puts out more amps than the fan requires, with 10-20% or more excess output. (Most cell phone charger will work too but will be a constant output of 5V usually)
Make sure your converter is unplugged from the wall. Cut off the plug on the end of the wire exposing the two wires. Do the same with the fan. Some fans have 2 wires and some have 3. Either are fine but if yours has 3 you wont need the yellow one so you can cut it short and get it out of the way. Split the two wires apart 2-3" down so you can split them nicely and have room to work on individual wires.
I do not have pictures of this because this fan was already wired and I took it apart for this How to post.
Strip the 2 wires on both the converter and fan. I usually do about 1/2" to 3/4". Please excuse the glue on the wires, I had it glued into place prior to taking the pictures.
Twist the wires from the converter to the fan. Pure black wire on the converter goes to the negative wire on the fan (black wire). Black wire with white stripe on converter goes with the positive wire on the fan (red wire).
Plug converter into your wall outlet making sure to keep the two wires away from each other so it doesn't short. I do this to make sure the fan is working, and is spinning the correct way. If its spinning backwards, or isn't working flip the wires. If it is spinning the correct direction unplug.
Step 5 Soldering Method
If you dont have a soldering iron skip this step and go to the next step (taping method)
Solder your first wire together making sure to have a good connection. Now solder the other wire. Take electrical tape and tape each wire separately to insure it wont short out. Now tape the two wires together to clean it up.
Step 5 Taping Method
Take your first wire and take a small piece of electrical tape, approximately 1" and wrap it tightly around the twisted wire making sure to completely cover where the wire has been stripped. Now do your second wire separately the same as the first wire. Now take a larger piece of electrical tape, approximately 2" and tape the two wires together creating one wire to clean it up.
Plug it in to make sure it is still working and you haven't made a mistake along the way. You are now ready to install it in your terrarium, vivarium, beside your lights to cool them off or whatever you are intending to do with the fan. Im lazy so I just take a little electrical tape and tape the fan in the corner of the aquarium making sure there is enough room behind the fan so air can be sucked in through the fan and out blowing over my plants.
Wiring more than 1 fan
Now if you want to hook up more than one fan you can do so on the same converter as long as the total input of amps of the fans is less than the output of the converter. Its always a good idea to leave 10-20% of room so you dont end up drawing too much amps from the converter on start up.
Ex: my converters output is 700ma or 0.7 amps.
0.7 x 0.20 = 0.14 amps
0.7 - 0.14 = 0.56 amps. This is how much amps I consider is safe to draw from the converter.
My fans are 0.06 amps.
0.56 / 0.06 =9.33333. So I can safely run 9 fans off this converter assuming all 9 fans draw the same amps.
If anyone has any questions feel free to post or send me a PM.