Cause : Over-speed comes when the motor has exceeded its maximum allowable speed as set in the servo drive parameters. This can lead to various issues, including mechanical damage, overheating, and system instability.

"alarm 26" in panasonic servo drive indicate "Over-speed" condition. This means the motor has exceeded its maximum allowable speed. This could be due to several reasons, such as incorrect parameter settings, mechanical issues, or external disturbances.

Troubleshooting Steps:

1. Check Speed Parameters:

• Maximum Speed Setting: Verify that the maximum speed setting in the servo drive parameters is appropriate for the motor and application. If the setting is too low, the alarm might trigger unnecessarily.
• Acceleration/Deceleration Rates: Ensure that the acceleration and deceleration rates are set appropriately to avoid overshooting the speed limits.

2. Inspect the Feedback Device:

• Encoder Feedback: Ensure the encoder is providing accurate speed feedback to the drive. A malfunctioning encoder can cause incorrect speed readings.
• Connection Integrity: Check the connections between the encoder and the servo drive to ensure they are secure and free from damage or noise.

3. Mechanical System Inspection:

• Load Conditions: Verify that the mechanical load is not causing the motor to accelerate beyond its limits. Sudden changes in load or inertia can cause speed fluctuations.
• Coupling and Alignment: Check that the motor is properly coupled and aligned with the load. Misalignment can lead to unexpected speed variations.

4. Monitor for External Disturbances:

• External Forces: Ensure that no external forces or disturbances are causing the motor to exceed its speed limits. This includes checking for environmental factors such as vibration or shock.

5. Review Control Signals:

• Commanded Speed: Check the commanded speed signals being sent to the servo drive. Ensure that the control system is not sending commands that exceed the motor's rated speed.
• Signal Integrity: Verify that the control signals are free from noise or interference that could cause erroneous speed commands.

6. Inspect the Servo Drive:

• Internal Diagnostics: Run any available diagnostics on the servo drive to check for internal issues that might affect speed regulation.
• Firmware Updates: Ensure the servo drive firmware is up to date, as updates can address known issues and improve performance.