Motor Over Speed

¿Qué significa Over speed ?

This fault occurs when the motor's actual speed exceeds its programmed maximum or a safe operating limit. This can be caused by encoder feedback issues, a runaway load (e.g., overhauling), or incorrect speed control parameters. Operating above rated speed can lead to mechanical stress, vibration, and potential damage to the motor, driven equipment, and the VSD's control stability. It's a critical safety concern in many applications.

• Faulty or disconnected encoder feedback (e.g., damaged sensor, loose cable connection, incorrect PPR setting P2-02).
• Runaway load condition where external forces drive the motor beyond its commanded speed (e.g., crane lowering an empty hook).
• Incorrect maximum frequency (P1-08) or speed limit (P1-09) parameters set below the actual or desired operating speed.
• VSD control board malfunction leading to incorrect speed command generation or misinterpretation of feedback signals.
• Overspeed protection parameter (e.g., P3-15 overspeed trip level) set too low or inadequately tuned.

Haga clic en los pasos para seguir su progreso.

1. 1

   Inspect encoder cable connections at the VSD and motor for integrity. Verify encoder pulses per revolution (PPR) parameter (P2-02) matches encoder datasheet.

2. 2

   Measure actual motor shaft speed using a handheld tachometer and compare it to the VSD's displayed speed (e.g., FOUT).

3. 3

   Verify parameter P1-08 (Max Frequency) and P1-09 (Max Speed Limit) are set correctly for the application's required speed range.

4. 4

   Check for mechanical freewheeling or an overhauling load condition. Implement mechanical braking or a flying start function (P2-03) if appropriate.

5. 5

   Cycle power to the VSD. If the fault persists and all external feedback appears correct, consider a VSD control board diagnostic or replacement.