Using computer Power Supply
#1
Thread Starter
Joined: Mar 2002
Posts: 2,692
From: RIP Frosty, Best Dog Ever
Let me start off saying I have built quite a few computer power supply conversions. I always add a 10ohm, 10watt resistors to hold the voltage up. I also always spilt the yellow and black wires to make 2 outputs. My latest was a 14A that I can run two chargers on, both at 5A and no issues. I just upgraded to two 10A chargers and grabbed a 610watt,44A on the 12V rail computer power supply, split the outputs, added the 10ohm 10watt resistor to the 5v rail and fired up both chargers at 10A and within a few minutes one of the chargers dropped an "input volt error" meaning the voltage dropped too low. Unloaded I am getting 12.8v but loaded it dips to around 10.5. This is a decent name in computer supplies, so I was a little surprised. Is there something I have missed?
Last edited by 2canSAM; 12-09-2012 at 04:33 PM.
#2
are you putting the resistors on the 12V ? you need to put them on the 3.3
V line . you want to offset the load that your putting on the 12V .
Good luck I am using mine at 24 Amps out works good.
V line . you want to offset the load that your putting on the 12V .
Good luck I am using mine at 24 Amps out works good.
#3
Thread Starter
Joined: Mar 2002
Posts: 2,692
From: RIP Frosty, Best Dog Ever
I always heard to put the resistor on the 5V. Are you sure about the 3.3V rail?
#5
Thread Starter
Joined: Mar 2002
Posts: 2,692
From: RIP Frosty, Best Dog Ever
Oh well I tried 
http://www.ultimaterc.com/forums/sho...d.php?t=122733
http://www.rctech.net/forum/radio-el...n-charger.html
http://www.tjinguytech.com/my-projects/convert-pc-ps
Last edited by 2canSAM; 11-16-2012 at 10:04 PM.
#6
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interesting. I'm getting back into this hobby after about 8 years. and you just cured my delema of what kind of charger I need. the dc units have awesome features for less $ than the comparable ac/dc units but I'd be forced to buy a power supply. but not anymore.
I have several old computer power supplies laying around.
I have several old computer power supplies laying around.
#7
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Joined: Mar 2002
Posts: 2,692
From: RIP Frosty, Best Dog Ever
interesting. I'm getting back into this hobby after about 8 years. and you just cured my delema of what kind of charger I need. the dc units have awesome features for less $ than the comparable ac/dc units but I'd be forced to buy a power supply. but not anymore.
I have several old computer power supplies laying around.
I have several old computer power supplies laying around.
#8
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well now that I had a look, I forgot I put my old one from my current rig into my moms since it went dead.
I just have some cheap old stuff laying around that says it's rated at 18 amps on the 12v rail. the one I have in my rig is an antec rated at 18A but it has dual 12v rails.
is there a write up for a dual 12v rail system?
I just have some cheap old stuff laying around that says it's rated at 18 amps on the 12v rail. the one I have in my rig is an antec rated at 18A but it has dual 12v rails.
is there a write up for a dual 12v rail system?
#9
Thread Starter
Joined: Mar 2002
Posts: 2,692
From: RIP Frosty, Best Dog Ever
well now that I had a look, I forgot I put my old one from my current rig into my moms since it went dead.
I just have some cheap old stuff laying around that says it's rated at 18 amps on the 12v rail. the one I have in my rig is an antec rated at 18A but it has dual 12v rails.
is there a write up for a dual 12v rail system?
I just have some cheap old stuff laying around that says it's rated at 18 amps on the 12v rail. the one I have in my rig is an antec rated at 18A but it has dual 12v rails.
is there a write up for a dual 12v rail system?
#11
Thread Starter
Joined: Mar 2002
Posts: 2,692
From: RIP Frosty, Best Dog Ever
I wouldn't look at anything less than 300watt for that charger. If you figure 50wx4 channels for 200w and build in 30% for lack of efficiency you're at 260w. I would really look at min 350w just to be comfortable.
#13
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Joined: Mar 2002
Posts: 2,692
From: RIP Frosty, Best Dog Ever
Hmm, are you getting any voltage on the 12 line? Any other indicators it is working? My fans have always worked so I would make sure it is still plugged in. Some of them have the fan wired directly but I have done a few where the fan was just plugged in, so it may have come loose.
#14
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and i went to the hobby store today and bought a thunder power TP610C-ACDC charger. but I got it home and it doesn't work.
they took it apart and the fuse is good. so I exchanged it for the X4. the one I actually wanted in the first place. I took the worker's advise about the other one being 80w instead of 50w. but to be honest the x4 is going to be more than enough for me for a while.
what do you think of the numbers of it?
Last edited by mtpocketsracing; 11-17-2012 at 06:59 PM.
#15
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Hmm, are you getting any voltage on the 12 line? Any other indicators it is working? My fans have always worked so I would make sure it is still plugged in. Some of them have the fan wired directly but I have done a few where the fan was just plugged in, so it may have come loose.



