[better] - Siemens Drive Fault Code 7902

If the motor features an integrated mechanical brake, the brake may not be releasing properly due to wiring faults or actuator failure. 2. Incorrect Drive Parameterization

Connect to the drive using Siemens software (such as STARTER, Startdrive, or the BOP-2/IOP-2 operator panels) to verify key parameters.

Disconnect the motor shaft from the load if possible, or attempt to rotate the machinery manually.

The (frequently displayed as F07902 ) is a critical safety and operational alarm that indicates a Motor Stalled condition. This fault triggers across multiple families of the Siemens SINAMICS product ecosystem—including the G120, G120XA, G120X, G115D, and S120 drives. When the drive's control unit detects that the motor cannot maintain its designated speed under load for longer than a predefined window of time, it immediately generates this fault to prevent hardware degradation. siemens drive fault code 7902

If the fault persists under sensorless vector control, execute a new motor identification routine: Set parameter (Identification at standstill).

"Elias. Line 4. Main stamper. It’s down. Totally dead. The screen is screaming at me."

The drive has detected a speed or position discrepancy indicating the motor is not rotating as expected based on its current frequency, typically after motor identification or during operation. If the motor features an integrated mechanical brake,

If the drive hasn't performed a proper "Motor ID" or "Stationary Measurement" (parameter p1900 ), it may have incorrect data for the motor’s electrical characteristics, leading to false stall detections.

This draft provides a general overview and might need adjustments based on the specific requirements or details of the Siemens drive model you're working with.

Fault 7902 on a Siemens drive is a "stalled motor" safety trip. By systematically checking the mechanics, verifying motor data, and tuning acceleration parameters, this fault can typically be resolved efficiently. If the fault persists after these steps, the motor may be undersized for the application, or there may be a faulty drive component. Disconnect the motor shaft from the load if

If you are using an encoder, ensure the is correct. If the inverter spins the motor in the opposite direction of the encoder feedback, a 7902 or 7801 fault will occur.

Ensure the encoder feedback direction matches the motor rotation direction; an inverted signal will look like a stall to the drive. If you'd like to troubleshoot further, let me know: The exact drive model (e.g., G120, S120, or V90).

If you are currently looking at a live fault panel, tell me:

Look at parameter p2175 (Motor stalled speed threshold) and p2177 (Motor stalled delay time). If your application requires a long time to break stiction, safely increase the delay time slightly to see if the drive passes the initialization phase.