ground and external power in inserted PCI card

Hello. I have PCI device with external power. It is 6 Pin PCIe to 2 x 4 Pin Molex LP4 Power Cable. For normal work I need in ground connected to Jetson AGX Xavier. Where I can connect ground cord?

Can you provide a picture to understand that you want to do? how do your PCIE device + external power connect AGX Xavier ?

https://drive.google.com/open?id=1-8O32Hnh0VJlaTOfKLBpa1u_S3hixx9v and https://drive.google.com/open?id=1-5_V0hORtqry0RZ_Ll_d0wEikZkMwGXv

This socket has some video card. GIGABYTE GeForce GTX 1080 or Palit GeForce GTX 1060 Dual 3GB for example

So you want to let your external power for PCIE and Xavier board have same Ground, correct?

if yes, you can connect to Xavier GND for power cord.

Where is Xavier board where I can connect Ground? Navigate pls. I see cable from wall socket to Xavier power source. It has Graund. I see cable from Xavier power source to Xavier board. It has’t Ground.

Aaaa sorry. You are to mean I can connect to GRN in power cable. From wall socket to Xavier power source Ok Thanks for answer

I don’t think that will do what you want. Either, the connection already exists (because it’s protective earth to protective earth,) or it won’t make a difference (between the power supplies are isolated.)

What you want to do is to connect the Ground OUTPUT of your separate power supply, to the SIGNAL GROUND of the Xavier.
You can find the signal ground on, for example, pin 6 of the 40-pin GPIO header.
You can find the ground of your power supply output according to the pinout of that power supply.

It’s also quite possible that your adapter card connects input-power ground to signal ground through its own PCB. If that’s the case, no additional ground connection is needed. But, if it doesn’t, or if you don’t know whether it does, then a ground wire from GPIO signal ground to power supply ground will ensure that the two stay at the same potential, and avoid “phantom voltage” to develop and cause problems.

@pavel.shtemenko my meaning is connect to Xaiver carrier board GND that is on Xavier DC_IN connector, but not power cable from Wall socket.

@rita_wangning I understand that you are to mean. Next problem is common problem for diff power source

@snarky Your pin don’t support power :) I mean 2 ampers and high. For example. Camera (1) from Cisco “eat” 1.5 ampers from power source. This power is going via external power socket in PCIe adapter. Adapter support 4 camers (up to 8)

Not sure if my understanding about your questions is correct, there should be some ground pins on PCIe slot, why do you still want to connect other ground for it?

Each pin on the GPIO header support 3 Amps of power.

However, assuming that your power supply connects to a “modular” type power supply on the PIC-Express board, you don’t actually need to route power through the GPIO; you just need to ground the second power supply to establish a shared reference ground.

All of this is very theoretical, though – can you post a picture of how you power the Jetson, how you power the PCI-Express board, and a schematic of your current connections? We may be missing something in the setup, or it may be the case that you don’t need to do anything extra – it all depends.

@Trumany It is common rule for 2 dedicate power source. I mean common ground. PCIe has’t ground. It has 0 or minus of power source.

@snarky https://onedrive.live.com/?cid=8702D6BB4727434F&id=8702D6BB4727434F!2076&parId=root&o=OneUp left tee where inserted power cable for PS + PCIe and PS for xavier. So both has common ground. Next, left, FP-650W which has PCIe socket, right xavier + PCI device. Cable from PCI device run to camera. This is view back https://onedrive.live.com/?cid=8702D6BB4727434F&id=8702D6BB4727434F!2077&parId=root&o=OneUp.

0 or minus DC is linked over PCI device. PCIe -> PCI device -> xavier -> 0 from xaviers power supply

The live.com file is not viewable by me.

However, it sounds like you already have all the ground connections you need, through the PCI express bus.

The ground network of DC power supply and signals are connected together on Xavier board。