Random error C306A0 and C283A3 without reason

Hello,

There are 5 UR cobots running on our machine, and controlled through Ethernet/IP.
The software version is 5.11.8.

We have the following issues frequently and randomly:

  1. C306A0, critical error. After PLC sends the power off/EP signal to cobot, this error occurs without reason.
  2. C283A3, power not removed from the motors while in Emergency Stop. It randomly happens to random cobot.

Does someone have an idea of them?

I don’t know if they’re related, but I’ve been having some weird things happen like that on 5.11.5 and now 5.11.8

To correct, it happens after PLC sends the power on signal.