Hello Everyone,

Our facility experience a problem that has a really inconsistent behavior that a hard to catch live. We have a system based on D445-2 DP/PN + 2 of S120 CU320-PN. System controls 16 axes inside machine (cartoner). Also want to mention only one of 6 identical machines gives us such problems.

D445 goes into STOP mode during production. Period between occurrences varies. Sometimes it takes more than month, sometimes it can happen twice per day. Only thing is consistent that is order of alarms in diagnostical buffer. It starts with bunch of Technological alarms -> 40-50ms -> PROFINET IO: station Failure -> 0-1ms -> Error occurred while reading a system or I/O variable -> Operating mode transition from RUN to SHUTDOWN: Start. It always refers to the same CU1 in station failure message. Technological alarms are not really explained in diagnostical buffer, but we have a screen on HMI that shows them. I am not sure that they reason for stoppage or the result of it. Indication on D445 - STOP Yellow / SF Red / SY/MT Green. CU has COM blinking and RDY differs case by case depends on drive fault being in fault or not.

We did check profinet/drive-cliq connection inside cabinet and on motors side, everything looks good. Changed CU1. Once tried small test and unplugged cable from CU1 to its drives and D445 didn't go to STOP, only showed SF and CU had RDY blinking orange.

Our next idea when machine will be available for testing is to try to unplug each profinet/drive-cliq cable and see if similar behavior will occur.

We really appreciate any advice this forum may give us.

Thank you.

Thank you for your reply.

Unfortunately, it provides no details besides the name of error itself. See attached screenshot.