I have a 300watt PC power supply. It is 17amps at 12V. Would this work for converting to a charger power supply?. I would be using it with a 10amp charger.

The power supply should be more than adiquate if your up to the task

I built my power supply from an old computer too. That'll be plenty

http://epbuddy.com/index.php?main_pa...roducts_id=333


http://www.rctech.net/forum/10692026-post6.html

PC power supplies will work, but if you get one that's got 5v Regulated and 12v Unregulated (Like most budget and PFC PSU's), you'll have to load down the 5v rail in order to pull the entire max wattage out of it.

I recently converted a 700w PC PSU myself, and had to load the 5v rail with a 3ohm resistor (50w Sandbar) in order to pull max power.

However, the old Compaq Proliant server PSU I just did the other day (500w) has fully regulated 12v, so no loading needed.

I'd pick up a cheap server PSU and convert that instead. Higher power, and less fuss. Plus, cheap!

There's a great read on this over at RC Groups: http://www.rcgroups.com/forums/showthread.php?t=1292514

Many of these seem to be over-rated and for other reasons don't quite make the rating when powering chargers (in addition to having low voltage many times)

However if we trust the numbers and go wit that then you could do any job up to 200 watts. OR you can do any 10 amp job up to 20 volts or less. If you go over 20 volts then it won't cut it.

Ok so here is my understanding of converting a PC supply. Add banana plugs to the +12v wires. Add a fan or some kind of resistor to the +5v side. I know there are a bunch of +12v wires, and +5v wires. Should I only run one wire to the banana plugs and use one wire on each side of the resistor, or should I run multiple wires to each of these. I hope this post isnt too confusing.

Use all of the common wires to reduce voltage drop since many chargers cut off at around 10 volts input. This may mean the difference of 20-50 watts of power available on some chargers. If charger you have can go to 4-5 volts then it may not make a hill of beans difference.

Ok sounds good. I will use all of the common wires. What about resistors? I know you need to add resistors to the +5v side. Can anyone give me an idea of what resistors I should get to try out? Can I just use one of the +5v wires for the resistor, or should I use all of them like on the +12v side?

I think you'd be fine to use just 1 5 volt wire , but I can't help with resistors. I've only ever used light bulbs and have had to apply up to about a 6 amp load (in an effort to increase voltage) on the 5 volt circuit. This was a very old ps though.

Coincidentally I don't do any mods to them anymore because I bought one of those digital power supply testers from newegg. It just plugs in and does the work for you. It also have a digital display on it. It cuts out almost all the work.

Ok sounds good. My nephew has a degree in computer science and networking so he can probably help me too. He has all kinds of PC repair tools and meters. One more quick question. When I go to radio shack, what banana plugs and banana plug sockets will work? I have found alot of 4mm banana plugs and sockets for stereos and speakers, will those work or is there something different?

is it possible that I won't need any resistance on the 5v side? If I am getting 12v or more on the +12v side without it, would I still need a resistor?

Bananas are all 4mm and pretty standard as far as I know. Some will get hot even at 10 amps though. I suppose that any insulated jacks will work fine. It is possible that you won't need any load at all (especially if you don't need 12 volts)

For $39 it's new and has ample power
http://www.hobbyking.com/hobbyking/s...ers_350W_.html

If my power supply puts out 17A on the +12v side, would it be possible to add a second set of banana jacks and run my 5A charger and my 10A charger?