hi there i am working on a project where i am connecting a car system to my pc to power the amp i will use a pc power supply. to combat the inconsistent power draws from the sound system i will be using a capacitor. what i want to know is, just say i had a psu, with 3 18 A 12v rails, is there a way i can connect these 3 rails together to get 54 A of current to put into the amplifier? thanks heaps...

You'd have to know more about the design of the psu. To say it is like a battery is not always true. A battery would work that way. PSU's for industrial equipment almost always have modules for each voltage unless noted. Not sure how crowbar circuits would react on that use. Consider a proper unit. Not sure burning down your car would be worth the time and trouble to find this out. I read it wrong and answer it wrong too. So get off my case you peanut.

its not for a car. the reason for using a psu is cause im putting this in my bedroom and dont want a car battery in here, also a std 12 v power supply to give that many amps is very expensive

Again burning down a house is expensive. Get a 120V to 12V converter. I read it wrong and answer it wrong too. So get off my case you peanut.

jefro The OP also needs DC power. Seems like it may work but why do you feel you need more than one 12V lead. Volts times Amps = Watts. 18A X 12V = 216 watts of power. How much power do you need to run the car deck?

I suggested a converter. A converter makes 12VDC from 120VAC doesn't it? An inverter makes 120VAC from 12VDC, he has the house voltage Guess not if you read this. http://support.radioshack.com/suppo... I still think that using devices like that is possibly dangerous. They make correct products that are safety listed. I think he is saying that he has a psu that has three leads. Each lead is listed to have a few amp's @ 12VDC. He wanted to parallel the lines to keep the voltage equal but increase the current. I read it wrong and answer it wrong too. So get off my case you peanut.

jefro My appologies, you are correct about the converter. I don't know that using a PSU in the manner the OP wants to is necessarily dangerous but I don't pretend to be a expert in this area. I think if the OP combined the leads that could be problematic. The OP's specs state 18A on each rail. I think that one rail should be enough, if they choose to try this at all. No doubt a device that is design for that express purpose would be better.