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
When this code appears, the drive is notifying you that a motor identification routine has been scheduled or is currently running. This routine is essential for the inverter to learn the electrical characteristics of the connected motor (such as resistance and inductance) to ensure precise control.
Apply a (start signal) to initiate the routine. siemens fault 0a7991
: While this alarm is active—especially if a rotating measurement is selected—you may be unable to save parameter assignments to the ROM until the process finishes. Common Troubleshooting Steps
: The alarm typically disappears automatically once the identification routine completes successfully. If you are performing a without the final
Set (Motor data identification and rotation test: Disabled).
: Ensure the Profinet/Profibus cable is securely plugged in and the PLC is powered on. Apply a (start signal) to initiate the routine
Removes the requirement for motor details for initial testing.
