PSU teaming

[trinislacker]

Would it be possible to connect several power supplies together to power a high current car amplifier

i am able to get a psu with 16A on the 12v rail at a decent price

but the amplifier requires about 120A

would jumpering all pin 14 and 15 and adding diodes to each 12v rail and connecting them together work?

if using a diode would work what would be the required diode current rating..individual rail current or total load current

a higher current psu with nut be possible in my case

 

[Fullmetal Chocobo]

Why not just get a car battery & charger?

 

[trinislacker]

the battery needed for that amperage costs almost double what the psus would cost and batteries have a limited recharge cycle which i don't even know what the average number is and then a battery would only last for and hour or 2 at max power draw

 

[trOver]

So the amp is going to be outside of the car?

 

[trinislacker]

you trying to get posts or something..cause that can't be a serious reply

 

[Modelworks]

On the battery side of things you can get a deep cycle marine battery with about a 600AH capacity for 100.00 . Marine batteries are designed to be totally discharged and recharged, unlike car batteries.

Still, if you want to do it with PC power supplies, I don't suggest combining supplies.
Switch mode supplies do not like to have their outputs combined with other switchmode supplies without some sort of circuitry in between to keep the supplies from feeding off one another. Also at 120A your lookin at a draw of 1440 watts, thats quite a lot for even several pc supplies, as most have fairly low 12V rails (20A) , putting most on the 5v.

So to do what you want you would need atleast 6 single rail supplies or 3 dual rails.

My choice would be the marine battery and a deep cycle charger if you want to do it cheaply. For more than that you need to look at a custom supply designed for 120A at 12V.

The Ham radio crowd has lots of these supply designs available, I would start my search there.

Edit:
I did a quick search on ebay.
Search for Cosel 12V 125 AMP Power Supply - PBA1500F-12

There were a number of them on there for under 100.00 and I think thats more of what you need. The voltage output the seller posted is a pretty wild swing, but that may be because there wasn't a load on the supply at the time.

 

[scott0482]

i have looked into this over and over.. it doesn't make sense to run a car amp in a house.. car stereo places use the battery + charger usually and you can only really play those for a short time a full volume..

also remember that car alternators put out 14.4v.. when you start at 12v and the amp has power spikes, it is going to drop below 12v which can cause damage to amps and cause clipping in the speakers..

i suggest getting and old school NAD 2200 PE amp.. they are beasts.. there are tons of other home audio amps with serious wattage.. i just don't know what anymore.. i haven't looked into this in years..

also.. i just remembered something..
http://www.scottsnyder.net/pictures/eclipse1.jpg

i did this before.. i ran a 65w amp and cd player off of a computer power supply with no problems..

thirdly.. what kind of car amp is this? is is actually pulling 120A ? are you going to run it full out? 1400 real watts in a building is loud...

i am going to go back to my original recommendation... marine battery + beefy charger.. the battery can handle / even out / quit supplying power durring the peaks.. no telling what happens to peaks that go through a 120v to 12v power inverter..

 

[DerekWilson]

Originally posted by: ModelworksStill, if you want to do it with PC power supplies, I don't suggest combining supplies.
Switch mode supplies do not like to have their outputs combined with other switchmode supplies without some sort of circuitry in between to keep the supplies from feeding off one another...

wow, we have this problem all the time.

when new graphics cards come out, or technologies like SLI and crossfire launch, we've got no choice but to use multiple PSUs. And we get all kinds of crazy problems from this

just another fun thing to deal with in the AT labs. but I second the fact that this isn't a good idea for anything production quality.

 

[Howard]

Originally posted by: DerekWilson

Originally posted by: ModelworksStill, if you want to do it with PC power supplies, I don't suggest combining supplies.
Switch mode supplies do not like to have their outputs combined with other switchmode supplies without some sort of circuitry in between to keep the supplies from feeding off one another...

wow, we have this problem all the time.

when new graphics cards come out, or technologies like SLI and crossfire launch, we've got no choice but to use multiple PSUs. And we get all kinds of crazy problems from this

How did you use multiple PSUs?