Convert an ATX Power Supply Into a Regular DC Power Supply!

Step 4 Grouping Wires

Group the 4 wire colors together and cut them to length to where you marked where the posts would go. Use the wire strippers to take off the insulation and stick about 3-4 wires into one tongue terminal. Then crimp them. The exact number of wires per voltage rail depends on the wattage of the PSU. Mine was a 400W and there are about 9 wires per rail. You need all these wires so that you can get all of the current rated for that rail.

Comments

[AntonMadness]

I would like to share a rule of thumb we use at my company concerning maximum current vs. wire thickness:
1mm^2 10A
1.5mm^2 16A
2,5mm^2 25A
4mm^2 32A
6mm^2 40A
My PSU is rated:
-12V 0,8A
-5V 0,5A
+3.3V 26A
+5V 35A
+12V 15A

I'm not thinking of using the negative voltages. The wires are AWG16 = 1.310mm^2. Because I don't think I will go to the max, 2 wires will give me enough room to pull 25A per channel(NOT simultaneously!).

So using two wires will give you 200% current without melting your wires and it will save you some room and time grouping ALL the wires.

[kvon99]

I tried this and when i tried to use it to power a car stereo head unit it just shut off the power adapter that is.. anyone know why?

[sschoemann]

Quite possibly drawing too much current... therefore the PSU reacted as if it had a dead short

[mkasp]

To make things neater you could solder that bunch of wires to some 12 or 14 gauge wire depending on the output current.

[spanky534f53]

That's a nice trick bundling the wires together to maximise current draw potential. Most other PSU conversions I've looked at on here don't have that. It makes perfect sense, but I wouldn't have thought to do it if I hadn't seen it first.

[tubbsey88]

wont grouping the wires together increase the voltage?

[Xunil]

No, the voltage stays the same. The current-handling capability is increased, because the current flows over all of the available paths (all of the wires). This means you can draw more current and not risk melting the wires.