Maximum system speed exceeded
Lenze · 9300 Series
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The maximum system speed, set by C0596, has been exceeded. This can be caused by an active load that is too high, the drive not being speed-controlled, or an excessively limited torque, leading to overspeed conditions.
Häufige Ursachen
- Incorrectly set maximum speed limit (C0596) that is lower than the actual required or commanded speed.
- Uncontrolled acceleration due to insufficient braking torque, especially with regenerative loads (e.g., lowering a heavy hoist).
- Drive operating in torque control mode without a speed governor, allowing the motor to overspeed with a light load.
- Mechanical decoupling of the load from the motor, causing the motor to spin freely at high speeds.
- Faulty speed feedback (encoder/resolver) providing incorrect, low speed values, leading the controller to command excessive output frequency.
Reparaturschritte & Checkliste
Klicken Sie auf Schritte, um Ihren Fortschritt zu verfolgen.
- 1
Review and adjust parameter C0596 (Maximum system speed) to a value appropriate for the application and motor's maximum safe speed.
- 2
Verify the braking resistor connection and value (P1-52, P1-53) and braking chopper functionality for applications with regenerative loads.
- 3
Confirm the drive operating mode (e.g., C0015 = 1 for speed control) to ensure it is actively regulating motor speed.
- 4
Physically inspect the coupling between the motor and the load for any damage or disengagement.
- 5
Verify the speed feedback sensor (encoder/resolver) signal integrity using an oscilloscope while the motor is running.
- 6
Check acceleration/deceleration ramps (P1-00, P1-01) to ensure they are not set too short, which can lead to overshooting speed limits.