: Ensure all motor parameters (rated voltage, current, power, speed, etc.) have been correctly entered in the commissioning software. Perform Motor Identification :

: The first step is always to refer to the user manual or technical documentation specific to your Siemens product. Siemens provides detailed manuals for its products, which include sections on troubleshooting and fault codes.

The Siemens code is not a permanent hardware fault, but rather a warning alarm indicating that the Motor Data Identification (motor tuning) is active. While this is a standard part of the commissioning process for SINAMICS drives like the G120 or G120C, it can be frustrating if it prevents the drive from starting in normal operation. Review of Fault A07991

The rating of 3/5 reflects the moderate severity of the fault code and the availability of potential solutions. While the issue can be resolved with proper troubleshooting and support, it still causes inconvenience and disruption to users.

“Configure the drive with the basic settings, the drive will do the 'auto tune' at the first 'run' command, wait for that to finish, the motor whistling for a bit and then go quiet. Re make the run command, the fault should go away.” Siemens SiePortal