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.

Comments

[coleyy]

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

[BC-45]

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

[lemonshark10]

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

[rocketman221]

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

[sora]

and cant enough electricity make a magnet out of it?

[rocketman221]

You need a coil of wire to make an electromagnet.

[sora]

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

[panmil1992]

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.

[rcguymike]

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?

[rcguymike]

Ohh, i got my answer here: http://www.instructables.com/id/Convert-an-ATX-Power-Supply-Into-a-Regular-DC-Powe/?ALLSTEPS

[marshnt]

whats with the leds r they doing any thing important

[bylerfamily]

No.

[marshnt]

So this is just an worthless light. "yawn" Go kill ur self

[bylerfamily]

No,the LEDs don't need to be there but the power supply can be used for various projects.

[junits15]

wait im confuzzled so im taking the psu apart and removing all wires except red black and yellowi got that much, then i put the corrisponding colored wires together as one? and this gives it more power? plz help me!

[bylerfamily]

Yes.

[junits15]

ok

[Lectric Wizard]

Are you sure you have a 10ohm 10W resistor ?? Ohm's law says I=E/R =5v/10ohms = .5A & P=E X I =5v X .5A = 2.5W . That resistor should get warm but not that hot. I have done this a dozen times & all I did was ty-rap the resistor to the inside of the PS case ... NICE INSTRUCTABLE THOUGH !!!!

[Junkyard John]

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!!!

[legless]

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

[GoodAtIt]

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.

[GoodAtIt]

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

[Mudbud]

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

[goeon]

loud?

[westfw]

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)

[izidor7]

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

[carebare47]

i took two capacitors from a power supply. they are quite small, but rated at 220uf and 200V. i am charging them with 4 9v batterys and the most i can get out of them is a small spark. What have i done wrong? i plan to use these for a railgun i made two years ago, the capacitor bank for that was given to me but fell apart. please help

[chip123]

i read this somewhere, but i'm not sure if it's true. A capacitor can only give an output of the equivilant to it's input, so if it holds 200v, then that is what it needs to be charged with.

[spasysheep]

If a capacitor is rated at 200v, that's the maximum voltage you can *safely* charge it with. If you charge it with 50v, it will output less power than it would if you charged it with 200v, as you put less power into it. If you charge it with 500v, it will burn out / malfunction / explode.

[GoodAtIt]

if you want to see big spark, you have to charge your capacitors to at least 30V. From my experience, shorting a high voltage capacitor is incredibly loud, so I just stick my my 40V 80000uF caps.

[carebare47]

so what would I charge them with?

[carebare47]

And also, would I damage them by shorting them out a lot?

[carebare47]

acctually, i am charging them with four 9V batterys, thats 36V isnt it? so why isnt it working well?

[GoodAtIt]

Check if you connected the 4 9V batteries right. They needed to be connected in series in order to have 36 volts. If it still doesn't spark big, then you need to go a bit higher, and it won't damage them by shorting them many times.

[klee27x]

Yes, it might. Some capacitors are specifically made for high discharge, such as used in flash cameras. Many other kinds will be damaged from being shorted, repeatedly.

[legless]

Just remember that the capacitor in a camera flash is not being "shorted" as such. When you hit the button current flows through a load made up of the Xenon flash tube and a couple of components. A dead short just using a wire is a completely different thing. The short circuit is a theoretical load of zero ohms (not in reality) allowing an almost infinite amount of current to flow (again not in reality). There is some resistance in any wire and some internal resistance in a battery or capacitor. Still the amount of current flowing in a short circuit can be very high even if just for a brief moment.

[carebare47]

i had wired them up positive to negitive to positive to negetive, and they do charge and spark, but its really small. oh well, nothing 2 liters of petrol cant fix. Thanks for the help =]

[spasysheep]

If you connect several capacitors together, they act as one capacitor. In series (what you're doing) they work at a higher voltage, but lower capacitance (http://www.play-hookey.com/dc_theory/series_capacitors.html). In parallel, they have a higher capacitance but lower voltage (http://www.play-hookey.com/dc_theory/parallel_capacitors.html)

[Muscelz]

dude, wow so messy :S duct tape, a kids workshop

[uberdum05]

I once read that a capacitor can regain it's charge after a couple of minutes so it's probably best to grab some croc - clips and clip on the resistor.