Computer Power Supply Question - 12V rail full amps

[Arunabha42]

So I will be converting a generic 600W desktop PSU to a power supply for charging LiPos. I have tested it powers on by pulling the green wire to ground and the yellow wires (12V rail) is providing 12V output.

The PSU I've got is rated at 25A on the 12V rail, which is 300W.

1. I want to use a 300W charger. There are many yellow wires in the wiring harness. Will I have to join all the 12V yellow wires to get the full current out of the 12V rail?

2. Also, if I want two 12V outputs to connect to two different chargers at 150W each, how should I go about joining the yellow wires and ground wires to their respective banana plugs?

Thank you.

 

[ViperTech]

On the one I made I wanted 2, 12 volt feeds so I just divided the wires in half and connected half of the wires to each banana connector and did the same with the ground wires, ground is ground and the 12 volt feed all comes from the same part of the power supply and by using more wires to connect the banana connector you effectively reduce the resistance by having more conductors.
I also made a 5 volt and a 3.3 volt connection on my power supply to be able to mess with other electronic projects.
There are several how to videos on this project so take a few minutes to review them, it helped me a lot.

 

[randyrls]

Be cautious; Some power supplies have more than one supply feeding the different 12V wires. In higher wattage supplies this is common. I have a 600W supply that has three different supplies feeding the different 12V rails. Cross connecting the supplies is not advised. Search for the model number on the supply to see if this is true in your case.