Stall Prevention (Overvoltage)

What does Stall prevention (overvoltage) mean?

The overvoltage stall prevention function has been activated, often during regeneration avoidance operation. This warning indicates that the DC bus voltage is exceeding safe limits, typically due to rapid deceleration or regenerative loads feeding energy back into the inverter. Sustained overvoltage can damage the inverter's internal components.

• Deceleration time (e.g., Pr. 8 Deceleration time 1) is set too short for the load's inertia, causing the motor to regenerate excessive energy back into the DC bus during stopping.
• Regenerative braking resistor is either missing, incorrectly sized, or faulty, preventing proper energy dissipation.
• Voltage surge on the AC input line causing the DC bus voltage to temporarily spike above the stall prevention threshold.
• Stall prevention (overvoltage) level (e.g., Pr. 16 Voltage stall prevention level) set too low for the application's braking requirements.

Click steps to track your progress.

1. 1

   Increase the deceleration time (e.g., Pr. 8) in 1-second increments, allowing more time for the motor to slow down.

2. 2

   Verify the connection and resistance value of the external regenerative braking resistor (if installed) against the inverter's specifications.

3. 3

   Check the AC input voltage at terminals R/L1, S/L2, T/L3 using a multimeter to confirm it is within the inverter's rated range.

4. 4

   Monitor the DC bus voltage display (e.g., using Pr. 08 "DC Bus Voltage" monitor function) during deceleration to determine its peak value.

5. 5

   Adjust Pr. 16 (Voltage stall prevention level) to a higher value, ensuring it remains below the inverter's maximum DC bus voltage limit.