Motor data identification (motor tuning) has not been performed, or the static/rotating measurements were not completed successfully.
Always maintain up-to-date parameter backups via an SD card or Siemens TIA Portal project files so you can quickly restore known working baselines if parameters are corrupted. To help diagnose this further, please tell me:
: Ensure the input voltage is stable, as a significant voltage drop can reduce the motor's available torque. siemens drive fault code 7902
. This typically occurs when the drive loses synchronism with the motor, meaning the motor is unable to rotate at the speed commanded by the inverter. Common Causes Missing Motor Data Identification
If the motor is new or the drive was recently replaced, . Do not increase fault thresholds yet. You must run the motor identification. Motor data identification (motor tuning) has not been
| Cause | Explanation | |-------|-------------| | | KTY84 or PT100 open circuit. Drive interprets infinite resistance as overtemperature. | | Short circuit | Short across sensor leads = zero resistance, also interpreted as fault. | | Wrong sensor type configured | Parameter p0600 (temperature sensor type) set to “no sensor” but sensor wired, or vice versa. | | Sensor connected to wrong terminals | Example: KTY connected to terminals for PTC thermistor. | | Faulty sensor | Internal damage to the thermistor or RTD. | | EMI interference | Noisy signal lines cause erratic resistance readings. |
G120XA solution to warning F7902 motor out of step - Siemens Do not increase fault thresholds yet
During commissioning, if the motor nameplate data (current, power, speed, torque) was entered incorrectly, the drive’s internal mathematical model will miscalculate a stall condition.