need a little help figuring out my PS ratings (pics) - RC-Monster Forums

RUSTY XL-5 · 12:38 PM

I have an old comp PS and couldn't figure out the ratings....

It says at 5v output is 18 amps, but at 12v output is only 4.2 amps? Whats up with that? How many amps could it send to my charger?

Thanks. :)

05.03.2009, 12:50 PM

4.2 amps. 12V takes more power than 5V which is why the 5V rating is so much higher.

RUSTY XL-5 · 05.03.2009, 12:52 PM

Quote:

Originally Posted by Frozen72

4.2 amps. 12V takes more power than 5V which is why the 5V rating is so much higher.

Ok, so when plugged into the standard American outlet, how many amps will it put out?

05.03.2009, 01:00 PM

4.2...I would get a better PS...thats only 50 watts...and after you factor in effiency closer to 40 watts

RUSTY XL-5 · 05.03.2009, 01:31 PM

Ok thanks. I thought is wasn't a very good one, just wasn't that sure.

magman · 05.03.2009, 01:40 PM

If you can get a 5-8amp 200 to 250watt would be much better. I have 2 ps that I made and 1 is 5A 250w and the other is 8a 400w

_paralyzed_ · 05.03.2009, 01:49 PM

Quote:

Originally Posted by magman

If you can get a 5-8amp 200 to 250watt would be much better. I have 2 ps that I made and 1 is 5A 250w and the other is 8a 400w

your wattage ratings are for all channnels combined. your 5 amp is only 60 watts (12volts x 5 amps = 60 watts) and your 8 amp is only 96 watts (12volts x 8 amps =96 watts) to get 400watts out of 8 amps would require 50 volts (50volts x 8amps = 400 watts) and all numbers are w/o factoring in efficiency

phildogg · 05.03.2009, 03:45 PM

the power supply says 146.7w on it so I'd say its a 150w power supply..
phil

_paralyzed_ · 05.03.2009, 04:30 PM

Quote:

Originally Posted by phildogg

the power supply says 146.7w on it so I'd say its a 150w power supply..
phil

you're right, it's a 150w power supply, but he wants to use it for a charger, which only uses the 12v+ channel

146.7w is for all channels driven. he's only going to use the 12v+ channel, which is rated at 4.2 amps, so he'd get 50.4w (12v x 4.2amps = 50.4)

Unsullied_Spy · 05.03.2009, 08:59 PM

You can get 500-700 watt PSUs on Newegg.com for a good price. If your charger can take more than 12v, use one of the negative rails (such as -5v) as your ground. +12v for positive and -5v for your ground gives you 17v. I used to re-wire computer fans to run on 15-17 volts all the time.