hanknmorgan

Quick question here. I just ordered an ICE charger, but I dont have a power supply. I was wondering if anyone has ever run their charger off their computer. I have a custom built PC that I built about 2 years and my power suppy is overkill for the system. It puts our 400w and 17 amps at 12v and I dont have anything special running on it to use much power. I also have several unused supply leads from the power supply and was wondering if I could just hook up to one to supply DC power to my charger. It seems logical to me if the power supply has the extra capacity. 12v DC is 12v DC correct?

I may be way off base here, but it seems like it should work to me. Thanks.

hanknmorgan

I have seen several threads about people using old PC power supplies with success. the only real modification they seem to need is to place a load on the 5v rail to make the full 12v since the unit needs a load. And to ground out the two connections that the motherboard uses to turn on power supply on newer atx units. Those two modifications would not be needed as the PC would already be taking care of those two problems. Any advice is appreciated. Thanks.

ford_racing

iTrader: (6)

It can and has been done, except you have to install some resistors to get it working, which basically will render the PSU useless for your PC.
Probably the best thing for you to do is buy a cheap PC power supply that puts out enough amps at 12v.

The main problem is that the charger will pull enough current as to melt the wires, you may get away with running 3 or 4 wires tohether to get the current, but in doing that you may kil your PC.

hanknmorgan

Alrighty then. I definately dont want to risk damaging the PC of course. I was just wondering if that would work. I guess I'll have to call around and try to find a good deal on a PC power supply somewhere. I cant spend much money as the charger was over my budget already. I guess I could always buy a cheap car or motorcycle battery or something and and just recharge it periodically. That way I could use it at the track as well. Any other ideas. I need to keep on the cheap, but I dont want to do anything sketchy either you know. Thanks.

AngryAsian

iTrader: (4)

If you don't want to shell out for a nice switch-mode PSU..

You can always pick up a high wattage comp psu and mod it, as you yourself have suggested. However - I personally wouldn't even contemplate running it whilst still powering a comp.

BY itself.. no worries..

Here's a couple of links to help you along:

http://www.rcgroups.com/forums/showt...368639&page=14

http://web2.murraystate.edu/andy.bat...owersupply.htm

Personally though - if I had just shelled out for a nice high-end charge. I certainly wouldn't skimp on the PSU. Why risk it?
A nice PSU will have readouts for AMPs pulled, and adjustable voltage.
For all you know - something in your comp PSU may be cooking, or that extra set of tire wamers has pushed you over the edge. WHoops...

It just doesn't make sense. It's not like you buy them everyday. It's one of those important one-offs..

rockdog200

A rivergate power supply is the only way to go. My distribution box got shorted and the power supply shut down until I removed the box then it started right up.

http://www.rivergatedist.com/Power_supply.htm

byron.s

try this. I have used these and they work just fine
http://www.mpja.com/productview.asp?product=16020+PS

hanknmorgan

Thanks again guys. I have another question then. My track has no AC power so everyone at race day either has uses a generator to power their dc power supplies or uses a car battery. I wont be able to race too often, but it would be nice to not have to pit sitting right next to street to hook the charger to my car battery. It may be more economical to just get a motorcycle battery or small cheapo car battery from wal mart or something and use that as my DC supply. I could just get a cheap trickle charger for it to keep it juiced up at the house. That way I could use it at the track as well and avoid the whole power supply deal all together. I dont have lathe or tire truer or any of that stuff so really all I need to run is the charger. How long can you run a charger off a car battery before it's drained. I know that depends on amp draw, etc, etc, but ballpark. Can you charge 5 or 6 packs at say 5-6 amps before the car batt dies? Thanks.

Smoking motor..

much more and lrp make some nice ones.

ford_racing

iTrader: (6)

If you want a battery, then definately get a deep cycle one, they last longer and are able to go months without being charged

andsetinn

The computer power supply should definitely work for the charger too. If you have the computer running you don't need to put in the resistors. (I've modified some computer power supplies without using resistors and they've all run fine). The original power wires from computer power supply should easily handle 8-10 amps without melting.

I still recommend that you buy quality dedicated power supply.
Don't use battery, the voltage gets lower as you use it, it's very heavy and if it short circuits it can blow up (you could put it in a closed box with fuse and fan to ventilate the box so gases can escape but that would just make it heavier).

Jack Smash

iTrader: (35)

I did the Powersupply mod to one that I wasnt using in any of my PCs. I think it came out nice. I currently have 2 sets of banana jacks hooked up to the 12v rail and will add another set later on down the road, and 1 set of banana jacks on the 3.3v rail to run my lathe and break in motors.

AngryAsian

iTrader: (4)

wow.... nice job!

You could sell those!!

I know a bunch of local runners who'd buy something like that!

hanknmorgan

Thanks guys again for the help. I priced out all my options on everything and decided to make my own. I called around and found a really cool computer surplus store nearby where I picked up a 300w 15A @ 12v ATX power supply for $15. It's used, but had a 30 day warranty so I brought it home and checked it all out. Looked good. So I went ahead with the modification process. I painted the case black and used the turn signal bulb trick for resistance on the 5v and added a switch. I had an extra fan from when I built our computer, so I through that one there for added cooling under heavy amp draw. It looks kind of nice. Not as flashy as the one in the pic above there (VERY NICE), but not too shabby. It puts out a steady 12.17 volts. I was unable to get an accurate amp reading because my cheapo multi meter wont register above 10a, but it's at least 10a since the meter goes into protection mode. It should be close to 15A, which is more than enough to do what I need it to do. All in all, abut $25 for 15A of DC power. And it has short protection built in apparantly. OOPS. Just switch it off and back on it powers back up. I'll post a pic or two on here shortly. Thanks for the help everyone.

-Hank