ATX Power Supply Question

[WeissWelsh]

Hi everyone. I'm using a 600 watt ATX power supply to power the 16-channel DC controller. My power supply says "12V1 - 18 Amps, 12V2 - 18 Amps and 12V3 - 15 Amps. Someone suggested I hook up the 12V1 to one bank and the 12V2 to the second bank. I know about using the black wires and yellow wires. But with all of the wires and connectors coming out of the power supply, how do I know which one is the 12V1 or 12V2 or 12V3?

 

Bob

[john fulkerson]

id use a meter to be sure

[starzen]

http://pinouts.ru/Power/atx_v2_pinout.shtml

 

i am guessing the V1 and V2 would be the two yellow wires (pin 10 and 11)

 

not sure about V3 but maybe that is the negative 12V

[starzen]

actually just read on that page

 

The standard specifies that two independent 12 V rails (12 V2 for the 4 pin connector and 12 V1 for everything else) with independent overcurrent protection are needed to meet the power requirements.

 

so it looks like the large connector only carries the V1 and V2 is on the 4 pin connector

 

http://pcsupport.about.com/od/insidethepc/a/atx-pinout-4-pin-12v-psu.htm

[WeissWelsh]

Thank you John and Starzen.

 

Starzen, that page was really helpful. I didn't realize that the standards mentioned which kind of connectors each rail would have. That made it easy to figure out. Thanks.

 

Bob

[westom]

Hi everyone. I'm using a 600 watt ATX power supply to power the 16-channel DC controller. My power supply says "12V1 - 18 Amps, 12V2 - 18 Amps and 12V3 - 15 Amps. 

 

Those supplies are often designed so that loads must exist on other voltages.  Some supplies can provide only 12 volts.  Others cannot.  The recommended meter is necessary to confirm that unique supply can provide current to the 12 outputs when the 5 and 3.3 volts are not loaded.

 

  Some supplies require a minimal load.  So a 10 ohm power resistor (ie from Radio Shack) might connect to those other PSU voltages to create a minimal load.