pcmanbob wrote: ↑
Thu Sep 20, 2018 3:26 pm
First off it would depend on how stable the 5v supply is on your ATX psu and then else is using it , as if you are driving motors from it you could find its subject to sudden voltage dips which your pi wont like.
Second how you actually connect this to the pi will depend on how the ATX psu has been modified to work with the 3d printer, as we don't know this we can say how you would make the connection.
Unless you can provide a lot more detail on what cables or output options are available on the ATX psu its going to be impossible for anyone to give you precise instructions on how to do this.
The basic idea is to take a 5V and ground cable from your ATX psu from some thing like a Molex 4 pin power supply connector and wire them to a micro usb plug so that you can connect it to your pi.
Red being 5v.
Black being ground.
You need to understand how your ATX psu is connected and being used by your 3d printer before attempting to connect the pi to it or you risk damaging your pi, you also need to do your own testing to prove the 5v output from the ATX psu is suitable.
Thanks for the answer, pcmanbob!
My PSU is a Corsair CX500, feeding the 3d printer heated bed via the PCI-E power connector. No modifications whatsoever were needed to supply the printer via the PSU, I only connected the cable and it works.
I've read a few times also about the 5VSB line from a 20-24 pin motherboard connector? Also that there is a way to shortcut some wires so that the PSU is always able to deliver the 5V from this line and not only when it's on standby?
The PSU has the following DC output cables:
- 1 motherboard 20+4 pin
- 1 CPU 4 x 4 pin
- 2 PCI-E 6+2 pin
- 4 peripheral (molex) 4 pin
- 5 Sata 5 pin connector
- 1 floppy power