The drive is waiting to perform a measurement routine. While this alarm is active, the drive typically cannot be started for normal operation until the identification is either completed or intentionally disabled.
How can resolve the alarm Code 7991 and 8526 - SiePortal - Siemens siemens fault 0a7991
The motor may rotate slightly or emit a humming sound for about 10–60 seconds while it measures stator resistance and inductance. The drive is waiting to perform a measurement routine