• Hardware

  • OAK-D-PoE Connection Errors, RuntimeError, X_LINK_ERROR, X_LINK_DEVICE_NOT_FOUND

Hi,

I am working with OAK-D-PoE for quite sometime now. My setup include two cameras connected with 50m cables with a PoE switch. At random I encounter three "RuntimeError" which are following:

  • RuntimeError: Failed to connect to device, error message: X_LINK_DEVICE_NOT_FOUND
  • RuntimeError: Cannot find any device with given deviceInfo
  • RuntimeError: Communication exception - possible device error/misconfiguration. Original message 'Couldn't read data from stream: 'detection' (X_LINK_ERROR)'

I am continuously encountering these errors. For now I have added exception handling and re-connection with some time delay. I followed the troubleshoot guide, but unfortunately the errors are still there.

Can anyone help me in troubleshooting this problem?

I had the same issues with my camera, because my dhcp setting were wrong.

Does your router have dhcp? Can you ping your cameras and are they in the right network?

If this is all correctly set up, keep in mind, that the OAK-D does need some time to restart (my OAK does sometimes need up to 30 seconds and then it also takes some time to get the dynamic ip).

I have assigned static IPs to camera to overcome this. The camera works perfect for hours but suddenly they stop working. When I restart the code immediately, It gives me one of LINK errors. And after waiting for sometime they start working again. Now in exception handling I wait for cool off period and try to reconnect the cameras.

Okay now I understood your Problem correctly.

So did you already try recording the temperature data from the camera?

No I don't have any idea about temperature data. Is there any correlation ?

  • erik replied to this.

    I haven't tested with shorter cables for longer times. I will increase delay as you suggested

      erik What are the maximum lengths of cables have you tested internally?

        erik After increasing the delay as you suggested, I am not encountering the LINK errors. Rather, the stream is stopped randomly

        • erik replied to this.

            Hi InzamamAnwar ,
            Have you tried the shorter cables as well? We did try with 15m (longest in our office) and it worked as expected. Also, are you using cat6 cable?
            Thanks, Erik

              2 months later

              Following are the steps I took to make cameras work with ~30m cables:

              1. Update the depthai: This was rather a simple step but I was hesitant to upgrade. Though I have regularly updated the firmware. Up-gradation from 2.19 to 2.21.
              2. I was getting raw frames from the color camera which may trigger CPU to 100% usage over time. This may result in halting of camera. Changed this pipeline to use encoded frame and it worked like a charm.

              @erik, Though, I don't know whether my deductions are correct or not, However, I would like to know what do you think?

              Thanks!