Testing PSU cables with a multimeter

kenkku · January 1

Hello!

I have a modular PSU that is missing most of its cabling. I have spare cables from other PSU manufacturers, however, reading online it seems like there is no standard when it comes to modular PSU cables, so plugging them straight into the hardware would be a bad idea. I wanted to go through and test all of the cables to check against the connector pinout schemes, and maybe modify them if necessary. My main concern is with my testing method. Where should I ground the multimeter when I test a pin on, say, the PCI cable? Is it okay to ground to the 24 pin connector's ground pins? The 24 pin cable is not modular in this model, so its pinout is standard.

As a disclaimer, I understand the risks when it comes to messing around with power supplies and I don't intend to get inside one. Any advice and tips will be appreciated!

RONOTHAN## · January 2

3 minutes ago, kenkku said:

Is it okay to ground to the 24 pin connector's ground pins?

Yeah, that's perfectly fine. It's also OK to just use the PSU's casing as that should be attached to ground.

You can also just look up the PSU, since a lot of them will have pinouts publicly available either from the community or the manufacturer itself, so you might be able to figure it out by just testing continuity on the particular cables.

kenkku · January 2

Just now, RONOTHAN## said:

Yeah, that's perfectly fine. It's also OK to just use the PSU's casing as that should be attached to ground.

You can also just look up the PSU, since a lot of them will have pinouts publicly available either from the community or the manufacturer itself, so you might be able to figure it out by just testing continuity on the particular cables.

Awesome, ty. And yes, I was going to look up some material too, just wanna be extra thorough for my own peace of mind.

BiotechBen · January 2

21 minutes ago, kenkku said:

Hello!

I have a modular PSU that is missing most of its cabling. I have spare cables from other PSU manufacturers, however, reading online it seems like there is no standard when it comes to modular PSU cables, so plugging them straight into the hardware would be a bad idea. I wanted to go through and test all of the cables to check against the connector pinout schemes, and maybe modify them if necessary. My main concern is with my testing method. Where should I ground the multimeter when I test a pin on, say, the PCI cable? Is it okay to ground to the 24 pin connector's ground pins? The 24 pin cable is not modular in this model, so its pinout is standard.

As a disclaimer, I understand the risks when it comes to messing around with power supplies and I don't intend to get inside one. Any advice and tips will be appreciated!

Cablemod also has a pretty good compatibility list on their site as well.