7902 ^new^: Siemens Drive Fault Code

If you are staring at a panel displaying “F07902” or “Fault 7902,” you know production has stopped. This article provides a deep dive into what this fault means, why it occurs, and—most importantly—a step-by-step guide to getting your machinery back online.

Understanding and Resolving Siemens Drive Fault Code 7902 The (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.

Unlike fault 7900 (Motor Blocked), which usually occurs at very low speeds, typically triggers when the motor enters a current limit above a specific speed threshold. The drive monitors the deviation between the speed setpoint and the actual speed feedback (or estimated speed in encoderless mode). Primary Causes & Parameters siemens drive fault code 7902

Before changing any electronic parameters, isolate the power and verify the mechanical health of the system.

: Incorrectly set motor data (voltage, current, or frequency) or missing motor identification (ID) runs. If you are staring at a panel displaying

According to Siemens Support , you should follow these steps to resolve the fault:

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. This fault occurs when the drive’s control logic

Detected at very low speeds/standstill when the speed controller is at its limit. Motor Overspeed

The key to resolving 7902 lies in systematic isolation. Always check the mechanical load first, verify the encoder signal integrity second, and fine-tune the stall detection parameters (, p1744 , p1745 ) third. By understanding the relationship between the drive's internal "motor model" and the physical reality of the rotating shaft, engineers can quickly differentiate between a genuine mechanical jam and a software sensitivity issue, ensuring maximum uptime for industrial equipment.

the fault occurs (e.g., instantly at startup, during acceleration, or randomly during runtime)