My Suped Up PowerSupply!

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Introduction: My Suped Up PowerSupply!

Inpired by other powersupply projects, I decided to build one myself, and ended up adding a lot of junk. See the steps on how to build one.

Step 1: Get a Powersupply

This is an old powersupply I got free from my school, and it pumps out 2-22 Amps on 5-V and 0-9 Amps on 12-V. Plus it has a automatic shut down circuit that shuts down the powersupply when short circuit is detected (it barely makes any spark when you join the positive with the negative).
You can get a powersupply easy from any computer repair shop, once you have your powersupply, it's time to put it to work.

Step 2: Safety

There are many ways that you can electricute yourselfs when doing this project, so please take the following precautions building this project, and don't get shocked and get a big blister like I did.

**NEVER EVER WORK ON YOUR POWERSUPPLY WHILE IT IS PLUGED IN**
*The capacitor inside holds enough electricity to cause an extremely painful shock, so discharge these capacitor with a power resistor with resistance over 10k ohm, just bend the resistor leads to the capacitor leads on back of the circuit board and make sure you hold the resistor with a pair of pliers because they tend to get very hot.

Step 3: Planing

Most old powersupplies have a heavily insulated line that have two wires in it, when these wires are connected, it turns on the powersupply, and is usually connected to the powerswitch of the computer. If you want to use the switch it came with, then be my guest, that is what I did, but it looks a little bad. If you want to use another switch, then cut off the existing switch and add your switch to the two wires.
For the output terminals, leave nothing but 4 strands of +5V (RED), 4 strands of +12V(YELLOW), and 6 strands of common negative wire(BLACK), if your powersupply has a 3.3V output, then you can leave out 3 strands of that too(ORANGE). Feel free to use more or less strands of wires for your output, the more you have, the better it will handle when pumping high currents.

Step 4: Putting It Together

Most powersupply has a minimal out-put current, for my PSU it is 2 Amps across the +5V. If you turn on the powersupply without any load, it might just burn out or have a wild voltage. So, I chose to buy a 10Watt 10Ohm resistor to consume that 2 Amps. I also found that it heats up so much that it started to smoke! So I decided to fancy it up, and added a big heat sink from a TV, and a cooling fan from another powersupply, even with all that cooling it still heats up to about 40 degrees C* on normal operation. I also added 4 super-bright LEDs connect parallel to the resistors and a 0-5k ohm pot to adjust the brightness. All that takes up 1 wire of 4 +5V wires that you left out, and 1 of 6 negative wires.

For the indicator LED mounted on my case, I used a 512ohm 1/4watt resistor and a green LED connected across 12 volts. that takes out 1 of 4 +12V wires you left out and 1 of 6 negative wires.

And now your left with 3 RED, 3 YELLOW, and 4 BLACK. I twisted them and used electrical type to finish it off. The terminal is solder connected to 20Amp Heavy Duty Alligator clips.

Step 5: Put It Through the Case

Plan how many hole you need to drill in the case, like the switch hole or the indicator LED hole.

Fit all your out put wires through the original hole and hot glue it shut so you won't be able to pull it out of the circuit board.

And Walla, your done! Make sure it is properly grounded, plug it in and turn it on.

Please post and questions or suggestions. I will be around for the next 2 weeks.

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    user

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    57 Comments

    you could also find the big 20 pin connector, find the green wire, and jumper it to any black wire on the same connector

    if discharge the capacitor from power suppply is it safe to remove

    5 replies

    just put a screwdriver between the leads if it is small. say the size of a camers flash cap.

    its not a very good idea to do that. the output from the capacitor can melt metal as well as damage the capacitor.

    user

    and cant enough electricity make a magnet out of it?

    You need a coil of wire to make an electromagnet.

    user

    you can make a permanent magnet out of lots of voltage running through a piece of metal or wire that's how some magnets are made

    You can always use a 100 watt bulb or two in series if capacitor voltage over 400 volt. It's the best way to discharge them.

    A word of advice! DO NOT USE SCISSORS OR SCREWDRIVERS TO DISCHARGE CAPACITORS!!!! I HAVE TRIED THIS AND THE SCISSORS HANDLE MELTED!!!! a little extreme I know, but it it did happen. I got a two degree burn for my stupidness. I have also heard reports of people who have had bits of handle of a screwdriver fused to thier hand from doing this. INSTEAD, BEND THE LEADS OF A LARGE RESISTOR, HOLD THE CERAMIC PART OF THE RESISTOR WITH PLIERS, AND TOUCH THE LEADS TO THE CAPACITOR LEADS. DO NOT USE A REGULAR PIECE OF WIRE AS IT WILL RESULT IN A VERY LARGE SPARK AND DAMAGE THE CAPACITOR!!!

    7 replies

    I think a capacitor you discharged might be a huge ones, but not the size of the capacitor used in a power supply. A typical power supply cap is only about 450uf at 200V, it is impossible to melt scissors or screwdriver metals. Like the cap bank shown in the picture, its 3 cap connect in parallell each rated at 40V 80000uf cap, I charged to 25V and discharged it with a screwdriver just for fun and it did melt the screw driver to the capactor terminals and made a huge spark plus deafening noise. It is correct to take precautions around capacitor specially discharging them, for I have injured myself many times.

    P1040838.JPG

    Here is a picture of me discharging one of them charged to 9 volts. -Woot-

    Capacitor.JPG

    were does everyone get these awesome caps?!?!?!?!!?
    i want dibs man.

    loud?

    450uF at 200V is a substantial amount of energy. 9J by my calcs. That's (slightly) more than the average disposable camera flash, and they produce impressive sparks like at http://www.quaketronics.com/
    The caps will PROBABLY be mostly uncharged when you short them, but a resistor is still a good idea. (don't forget that the energy equation has V**2,
    so a cap charged to 100V has 16 times the energy of the same cap charged to 25V)

    i can just imagine what for a bang would make a 2,5V 3kF cup 10 000j maybe the bang wouldn't be big????

    Also even low voltage capacitors can be discharged quite successfully using a household mains rated lightbulb.

    on the psu I'm using it has a blue, purple, brown, grey, and green instead of 2 "heavily insulated" wires. is there a way to find out which ones turn it on or has anyone used one of these. it's an ACBEL API-9635. thanks. On further examination of the PCB where they connect to it the blue says -12 Volts, purple says +5VS, Green says ON/Off, brown isn't even connected(wth), and grey says PG. would that mean connect grey and green with a switch?

    1 reply

    whats with the leds r they doing any thing important