Siemens Fault 0a7991 !!better!! -

: The alarm typically disappears automatically once the identification routine completes successfully.

The Siemens fault code (often searched as 0a7991 ) specifically indicates that Motor Data Identification is activated . This is not a critical equipment failure but rather a status alarm triggered during the commissioning or configuration phase of Siemens SINAMICS drives , such as the G120, G120C, and G150 series. Understanding Alarm A07991 siemens fault 0a7991

Apply a (start signal) to initiate the routine. : The alarm typically disappears automatically once the

: If testing the drive standalone, set p2030 = 0 (No protocol) and perform a "RAM to ROM" save. Technical Summary Table Default/Action Description p1900 Set to 0 Disables the motor identification routine. p0971 Set to 1 Understanding Alarm A07991 Apply a (start signal) to

If you are performing a without the final motor, attaching a smaller spare motor can sometimes bypass identification faults by providing enough feedback for the drive to initialize. Alarms A 7991 and A8526 - SiePortal - Siemens

Either the network connection (profibus/profinet?) between the PLC controlling the drive is powered off, network connection lost ( Siemens SiePortal How can resolve the alarm Code A7991 - SiePortal - Siemens

The most direct fix is to allow the drive to perform the check.