Motor Step Out

What does E.SOT mean?

The inverter output is shut off when the motor loses synchronization during operation, a condition specifically monitored under PM sensorless vector control. This fault indicates a loss of control over the motor's rotor position, leading to erratic operation.

• Overload condition exceeding the permanent magnet (PM) motor's synchronous torque capability.
• Incorrect PM motor parameters entered into the inverter (e.g., Pr.1130 to Pr.1134 for PM motor constants).
• Rapid acceleration or deceleration rates exceeding the motor's dynamic response limits.
• Instability in the sensorless vector control algorithm due to motor characteristics not matching the model.
• External mechanical shock or vibration causing momentary loss of rotor position synchronization.

Click steps to track your progress.

1. 1

   Perform an autotuning procedure specific to PM motors (e.g., using Pr.1130 and Pr.1131 with Pr.1100 set to 1) to accurately identify motor parameters.

2. 2

   Reduce acceleration/deceleration times (e.g., Pr.7 Accel time, Pr.8 Decel time) to prevent exceeding the motor's dynamic limits.

3. 3

   Monitor actual motor speed (e.g., Pr.206 Output frequency) and current (e.g., Pr.205 Output current) to observe behavior during the step-out event.

4. 4

   Verify the actual load on the motor against its rated torque to ensure it's not consistently overloaded.

5. 5

   Ensure the PM motor's specifications (e.g., poles, flux linkage) are correctly entered into Pr.1130 to Pr.1134.