Computer PSU wire question?

Hi all,
I want to turn an old computer PSU into a lab bench PSU.  After cutting all the connectors at the end of the cables, I've noticed that some of the common (black) wires were made of copper, while some of them were made of nickel \ aluminum (Silverish).
The same is true for the +5V (red) cables.
It's not the first PSU I noticed that had the different materials, and I was wondering:

1) Why are there two different kinds of wire?

2) Is it OK to ignore the wire material and just splice all the blacks together, and all the reds together?

Thanks!

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That is a little odd. I mean the fact the output wires from your power supply are made from two slightly different kinds of wire.

I am guessing the silverish wire is also stranded copper, but copper strands that have been "tinned" with some thin layer of solder, or something like it.

If you want to confirm that all black insulation covered wires belong together, you can just follow them back to the power supply board, and confirm that they're all soldered together there. Or you could use an ohmmeter (which will likely be a multimeter set to its lowest resistance measuring setting) for to confirm all the black wires are already connected together.

And you can do the same with all the red wires, or all the yellow ones, etc. Follow them back to the board, and/or use an ohmmeter to confirm they're already connected.

By the way, the reason I am guessing the silverish colored wire is tinned copper, is because it has to be made of some metal that is easy to solder to, because all those wires are connected to each other by being soldered to the same node on the power supply board. Or at least that was true of the last half dozen computer power supplies I took apart.

Morgantao (author)  Jack A Lopez3 years ago

I took apart 3 PSUs from different computers this week, they all had two wire materials.

One was a 5 month old PSU from a computer that caught on fire (That one was dead, all the capacitors leaked).
Another was about 4 years old, and worked fine until I connected all blacks together, reds together, etc. Then it died no me, for some unknown reason. That's when I started wondering if the plain copper and the coated copper wires shouldn't have been connected together.
The third one, is a 12 year old power supply, which surprisingly still works, so I decided to ask before I repeat any mistakes.

Good idea to check for continuity, didn't even cross my mind, LOL.

verence3 years ago

1) Maybe the PSU was assembled with pre-made connector-wire assemblies. Like 3.5" molex connector for HDD from company and main board connector from company B

2) Should be okay. If you want to be sure, check that they are connected in the PSU as the others said.

Morgantao (author)  verence3 years ago

That's what I thought, as some of the different wires were harnessed together, some going to molex connectors, some to the main board connector etc...

Wire materials won't matter.