Selected SERCOS phase could not be implemented error in phase 0 transition.

What does 844 mean?

An error occurred during the transition to SERCOS phase 0, preventing the selected SERCOS phase from being successfully implemented. This is a servo loop or drive fault, indicating a critical issue in the SERCOS state machine, with no error recovery possible.

• Error during SERCOS phase 0 transition.

Click steps to track your progress.

1. 1

   Measure input supply voltage and DC bus voltage at the affected drive and verify against nominal specifications.

2. 2

   Inspect all SERCOS fiber optic cables for physical damage, proper routing, and secure connections at both controller and drive interfaces.

3. 3

   Verify SERCOS communication parameters (e.g., ring configuration, cycle time, drive address) in both the controller and the drive against the machine's configuration backup.

4. 4

   Check diagnostic LEDs on the SERCOS interface of the drive and controller for communication activity or error indications.