Cause : Absolute encoder overspeed error comes when the encoder rotates faster than the specified rate when it is battery-powered.

"alarm 41" in panasonic servo drive indicate "Absolute encoder overspeed". This means the encoder's speed has exceeded its allowable operating range. This can occur when the motor or system moves faster than the encoder can accurately track, potentially leading to missed counts or errors in position feedback.

Troubleshooting Steps:

1. Check the Motion Profile:

• Verify Speed Limits: Ensure that the motion profile, including acceleration, deceleration, and maximum speed, is within the encoder’s specifications. If the system is programmed to move faster than the encoder can handle, this will trigger an overspeed alarm.
• Reduce Speed: If the motion is too fast, consider reducing the speed settings in the servo drive or control system to avoid exceeding the encoder’s capabilities.

2. Inspect the Encoder and System:

• Encoder Condition: Examine the absolute encoder for any signs of wear, damage, or misalignment that could impact its ability to track motion accurately at high speeds.
• Mechanical Inspection: Check the mechanical setup to ensure there are no issues like excessive friction, misalignment, or loose components that could cause erratic motion or overspeed conditions.

3. Review System Configuration:

• Encoder Specifications: Double-check that the servo drive is configured correctly according to the encoder’s specifications, such as pulse counts per revolution and maximum speed ratings.
• Parameter Settings: Review the servo drive parameters related to speed limits, acceleration, and deceleration to ensure they are appropriate for the application and within the encoder's limits.

4. Monitor Environmental Factors:

• Vibration and Noise: Ensure that the system is not subjected to excessive vibrations or electrical noise, which can cause the encoder to register incorrect speed or position data.
• Temperature: Verify that the operating environment is within the temperature range specified for the encoder, as extreme temperatures can affect its performance.

5. Check Power Supply Stability:

• Voltage Levels: Ensure that the power supply to the encoder and servo drive is stable and within the specified range. Fluctuations in power can cause the encoder to misread speed.
• Electrical Interference: Minimize electrical interference from other equipment that could affect the encoder signals.

6. Reset the Alarm:

• Manual Reset: After addressing any potential issues, reset the overspeed alarm on the servo drive. This may involve a specific reset command or simply power cycling the system.
• Test System Performance: After resetting, perform a test run at the intended speed to ensure that the overspeed condition does not recur.