F-device Safety Watchdog Time Zero (V3 CPU)

What does 28683 mean?

The F-device instance <n> for AC500 V3 non-safety CPU PM56xx is configured with a safety watchdog time value (F_WD_Time) of 0 ms. This indicates an invalid or unconfigured watchdog timer, critical for maintaining safe PROFIsafe communication and preventing the module from going to a safe state.

• Watchdog timer within the V3 CPU has expired, indicating a system hang or process failure.
• Software or hardware issue causing the F-device to stop responding.
• Persistent interrupt or communication deadlock.

Click steps to track your progress.

1. 1

   Check the Safety PLC configuration for the F-device instance <n>.

2. 2

   Verify the F_WD_Time parameter is set to a valid non-zero value.