In the majority of Siemens inverter documentation, Fault 7902 indicates that the drive has detected an internal hardware issue or a severe output stage anomaly that cannot be resolved by standard parameter adjustments. It often signifies that the Inverter Power Module (PM) has detected a short circuit, an earth fault, or an internal component failure (IGBT failure).
Settings on the control unit do not match the power module.
If the drive is still running but tripping intermittently, check the diagnostic parameters using the BOP (Basic Operator Panel): fault 7902 siemens
Understanding why this fault occurs helps pinpoint the quick fix required to clear it from your Siemens TIA Portal or Starter software workspace.
I can provide the specific parameter numbers and paths tailored to your exact system. In the majority of Siemens inverter documentation, Fault
Keep in mind that the specific troubleshooting steps may vary depending on the device model, software version, and application.
Changing a control unit without running the safety synchronization. Step-by-Step Troubleshooting and Resolution If the drive is still running but tripping
Safety parameters were changed but not actively confirmed.