Question about power supplies

[netzero 10+ year member]

I have two computer power supplies that iv been using just fine to power my little 2 channel in the house. I'm going to get another amp to run two little subs, but i had some questions about the supplies.

Is it better to run a car amp and a higher voltage and lower current, or the other way around. Example: 12v at 10 amps, versus 15v with more like 7-8 amps?

Also, i read that you can run multiple PSU's to one amp, how? Do voltages add up, do currents add up, series, parallel, how does it work? Thanks all

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[netzero 10+ year member]

Anyone have some insight?

 

[93dakota 10+ year member]

I have two computer power supplies that iv been using just fine to power my little 2 channel in the house. I'm going to get another amp to run two little subs, but i had some questions about the supplies.
Is it better to run a car amp and a higher voltage and lower current, or the other way around. Example: 12v at 10 amps, versus 15v with more like 7-8 amps?

Also, i read that you can run multiple PSU's to one amp, how? Do voltages add up, do currents add up, series, parallel, how does it work? Thanks all

I would think that an amp would be fine running at 15v. most amps are running on 14.4v in a car while it is running. you may be able to run the amps even up to 18v depending on if the amp was meant to be able to run on a 16v system.

As for running multiple power supplies that is completely possible. if you run both the pos and both the neg together the voltage will be that same as just one and the amps would be split between the two. basically run them in parallel.

 

[netzero 10+ year member]

Ok, so if i have one psu that does 10 amps @ 12v and one that does 13 amps at 12v, in parallel would my car amps see 23 amps @ 12v? Also, would they be fine together, or would i need a diode on the positives? Thanks

 

[93dakota 10+ year member]

Ok, so if i have one psu that does 10 amps @ 12v and one that does 13 amps at 12v, in parallel would my car amps see 23 amps @ 12v? Also, would they be fine together, or would i need a diode on the positives? Thanks

The amp would not see 23 amps. the amp is what decides how any amps are going to be drawn. They should be fine together and do not need a diode but you will not be able to draw over 20 amps. you have to go off the lower amps because the amps are split evenly so if you go over 10 amps for one and it trips its breaker then the other power supply will see over 20 amps and it will blow its breaker.

 

[Scoobydoo 5,000+ posts]

for some reason talking heads - burning down the house comes to mind in this thread

 

[netzero 10+ year member]

for some reason talking heads - burning down the house comes to mind in this thread

Lol. Unparalleled they've been running fine for months.

I'm just going to forget wiring them together, and just get two higher amperage PSUs online or something lol... Thanks man

 

[Gebrochen 10+ year member]

Get something like this, but maybe look for one that's not so beaten up:

http://cgi.ebay.com/Mean-Well-SE-600-15-15V-40A-Switching-Power-Supply_W0QQitemZ150332947072QQihZ005QQcategoryZ58288QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

Or go for something like an Astron or Pyramid:

http://cgi.ebay.com/Astron-RS-50A-50-Amp-Power-Supply-AC-to-DC-NR_W0QQitemZ230333293789QQihZ013QQcategoryZ58288QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

I bought a 95A 15V forklift charger for about $100. Coupled with a battery, it's enough to meet all my needs.

 

[mud 10+ year member]

Thanks Gebrochen, those are some great suggestions. I've been looking for a cheap power supply capable of some real amperage.

Also, I wouldn't recommend trying to wire ATX power supplies in parallel. Depending on the supplies, you might be ok . . . or you might blow them up. Big diodes highly recommended for anyone who wants to try.

 

[netzero 10+ year member]

Very nice Gebrochen, that sounds like a pretty good setup. I'll look into those.

 

[IDSkoT 5,000+ posts]

I have two computer power supplies that iv been using just fine to power my little 2 channel in the house. I'm going to get another amp to run two little subs, but i had some questions about the supplies.
Is it better to run a car amp and a higher voltage and lower current, or the other way around. Example: 12v at 10 amps, versus 15v with more like 7-8 amps?

Also, i read that you can run multiple PSU's to one amp, how? Do voltages add up, do currents add up, series, parallel, how does it work? Thanks all

In terms of voltages, I'm honestly not sure.

But, multiple PSUs: the source of the power is getting split, but will draw as much as it can from both equally. It's the same as having two batteries hooked up to one amp. I'm not sure how you would hook it up. You could try it with some quick blowing fuses, just in case it shorts, your PSUs won't bust. First I'd just try hooking up the positive+positive to the positive, and same for negative and try that.

BTW: You can make a 13.8v @ 10 amp PSU for ~$100 bucks, or if you're more tech savvy, a lot cheaper. $30 or less depending on the parts you have around your house.

PM me for the schematic.

 

[netzero 10+ year member]

Ok cool. I found some 40 amp diodes online for like 3 bucks, and i think i would get those if i was going too. One of those supplies that Gebrochen suggested would be the best i think in this case... i might try to get one of them someday. Or sunbeam makes a computer psu that puts out 12v @ 25 amps, for like $19 on newegg... not bad for the price. This is all without a battery of course.

 

[Gebrochen 10+ year member]

Diodes have a 0.7 - 1.7 voltage drop. If you have power supplies to spare laying around, I think I'd try it without them. I have 3 that do 12V @ 22A and that's how I'm planning to hook them up for a bench-test setup in my garage. If I get around to it anytime soon I'll post back to this thread.

If you hook a regular power supply to a battery, don't leave it on all the time because you'll overcharge and ruin your battery.

 

[netzero 10+ year member]

Diodes have a 0.7 - 1.7 voltage drop. If you have power supplies to spare laying around, I think I'd try it without them. I have 3 that do 12V @ 22A and that's how I'm planning to hook them up for a bench-test setup in my garage. If I get around to it anytime soon I'll post back to this thread.
If you hook a regular power supply to a battery, don't leave it on all the time because you'll overcharge and ruin your battery.

Ok sounds good, please do. I have some im gonna try, but they sit at a little different voltage, and one a 10A and the other is 13A so im not sure how well they would work together... but let us know