Step 3: Presenting the Power
OK from all the other tutorials I've read there are a lot of different methods of connectors for connecting your devices to the power, Ill start with the best one and work my way down to the worst.
Some tutorials will tell you to stuff it all inside the one case but that is dangerous and will make it very warm and crushed. I recommend using a external enclosure.
1.Adding a Variable Resistor:
I personally think this is the best method as this can provide any voltage between 1.5 to 24 volts. The reason that its 22v and not 12 is because it uses the Blue wire which is -12 volts not the common earth (black wire). You will need:
LM317 or LM338K Voltage regulator
100nF Capacitors (ceramic or tantalum)
1uF Capacitors Electrolytic
1N4001 or 1N4002 Power Diode
120 Ohm resistor
1x 5k Ohm variable resistor
First build the circuit from the main picture and connect your +12 and -12 volt lines. Now drill holes in either the power supply or an external case to fit the variable resistor, All the other circuitry should be kept inside. I suggest now adding Two terminal blocks so you can wire devices directly in. You could also connect some alligator clips in to the terminal blocks aswell. When you turn the variable resistor the voltage should range between 1.5 and 24 volts. NOTE:There is a typo in the main picture it should read +24v variable instead of 22v. If you had an old volt meter you could wire it in to the output so it can tell you what voltage you are at.
2. Binding Posts
2nd is using binding posts to connect equipment. First drill hole for the binding posts (make sure to wrap the circuit board up in plastic as metal shards can short circuit it) then check they are the right size by inserting the posts and tightening the bolt behind them. You chose what voltage to hook up to what post and how many posts to put in. The colour Codes for all the wires are:
There is a image below using the binding post method.
3.Basic Crocodile Clips
If you don't have that much experience or don't have the above parts and for some reason can't buy them you can just hook up whatever voltages you want to Crocodile clips. If you do chose this option I would suggest a sleeve over the Crocodile clips to prevent short circuits.
Tips and Troubleshooting:
- Dont be a bit afraid to spice the box up a bit, you could add leds, stickers or anything!
-Make sure you are using a ATX Power Supply. If it is a AT or older power supply it will most likely have a different colour scheme for the wires. Unless you have some data on the wiring dont attempt this as you could get caught on the wrong end of a wire and get your head blown off.
- PSU means Power Supply Unit
-If the LED on the front doesn't come on chances are you have the leg wired up the wrong way around just switch the wires on the legs and it should light.
-Some modern Power supply's will have a "sense wire" this has to be connected to power for the Power supply to function. If the wire is grey connect it to an orange wire, if it is pink connect it to a red wire.
-The High wattage power resistor can become quite hot; you could use a heatsink to cool it down but make sure it doesn't short anything out.
-If you insist on putting everything inside, you can put the fan on the outside rather then the inside.
-The PSU fan can be noisy , it is powered by 12v. Since it isn't power computers anymore and doesn't heat up as much you can snip the red wire of the fan and connect the orange 3.3v wire. Keep an eye on your circuit after you do this, if it produces too much heat connect the fan back up to the red wire.
CONGRADS You have successfully finished your Power supply!
Thanks to other tutorials on Wikihow and Instructables because I used some of there pictures.
This instructable was published quite a while ago and unfortunately I am no longer in a position to provide support for it. But there's lots of good stuff in the comments below. Thanks for all the likes, shares and follows!