Siemens Drive Fault Code 7902 [top] May 2026

In Siemens SINAMICS drives, fault code F07902 indicates a motor stall caused by mechanical overload, incorrect motor data, or improper configuration. Troubleshooting involves verifying motor nameplate data (p304-p311), running identification (p1900=2), and adjusting stall parameters like p2178 to prevent nuisance trips. For detailed troubleshooting steps, visit Siemens Support. sinamics drive motor fault 7902 - SiePortal - Siemens

Understanding and Resolving Siemens Drive Fault Code 7902 The Siemens Drive Fault Code 7902 (often displayed as F07902) is a critical error indicating a "Motor Stalled" condition. This fault occurs when the drive’s control logic determines that the motor is not rotating as expected despite receiving power, or when the deviation between the calculated motor speed and the actual measured speed exceeds defined limits.

While this fault is common across various series including SINAMICS S120, G120, G120XA, and G115D, its root causes can range from simple mechanical blockages to complex parameterization errors. Primary Causes of Fault 7902 siemens drive fault code 7902

Understanding why the drive triggers a stall fault is the first step in troubleshooting. Common triggers include: SINAMICS G120XA fault F07902 - ID: 109773411 - Support

In industrial automation, encountering a Siemens Drive Fault Code 7902—specifically F07902: Motor Stalled—can bring production to a grinding halt. This fault is common across various Siemens Sinamics series, including the G120, S120, and G120XA models. Understanding what this code means and how to systematically troubleshoot it is essential for minimizing downtime. What is Siemens Fault 7902? In Siemens SINAMICS drives, fault code F07902 indicates

Fault F07902 indicates that the drive has detected a motor stall. This occurs when the actual speed of the motor deviates from the speed setpoint by more than a specified threshold for a set period.

While related to F07900 (Motor Blocked), F07902 typically triggers at higher speeds or under specific torque conditions where the drive is attempting to move the motor, but the feedback or calculated model indicates it is not following the command. Common Causes of Fault 7902 sinamics drive motor fault 7902 - SiePortal - Siemens Prevention and Best Practices To avoid future occurrences

Prevention and Best Practices

To avoid future occurrences of fault code 7902:

  1. Use shielded cables for temperature sensors, grounded at drive end only.
  2. Document p0600 settings in your machine’s maintenance log.
  3. Implement predictive maintenance: Log r0035 weekly. Sudden deviation from ambient indicates future failure.
  4. Firmware updates: Some early versions of Sinamics firmware misreported some sensor faults as 7902 incorrectly. Check Siemens support for relevant updates.
  5. Thermal imaging during quarterly PM (predictive maintenance) can catch cooling degradation early.

5. Quick fix (if safe)

5. Diagnostics Steps

  1. Check LED status on drive:
    • G120 Control Unit: BF (Bus Fault) LED red → indicates bus error.
  2. Verify PLC status:
    • Is PLC in RUN? Are other nodes communicating?
  3. Check hardware:
    • PROFIBUS: Terminating resistor ON at both ends; check connector & shield.
    • PROFINET: Link LED active; no port errors.
  4. Review drive parameters:
    • P0700 = 6 (fieldbus as command source)
    • P0922 → set to correct telegram (e.g., 1, 352, etc.)
    • P2040 → increase from default (e.g., 100 ms to 500 ms temporarily for test)
    • P8840 = 1 (enable fieldbus interface)
  5. Check master configuration:
    • Device address matches drive station address (P0918 for PROFIBUS).
    • Telegram type in hardware config matches P0922.
    • Cyclic data exchange enabled in master.

Step 1: Verify Fieldbus Master Operation

Guide: Troubleshooting Siemens Drive Fault Code 7902