Shihlin servo fault codes 2

Shihlin Servo Fault Codes 2

This page covers Shihlin servo alarm codes AL.06 to AL.13, including overspeed, pulse-command, position-control, communication, encoder, cooling, IGBT, memory and motor-matching faults.

Shihlin servo fault codes are divided into two pages:
Shihlin Servo Fault Codes 1 – AL.01 to AL.05 | Shihlin Servo Fault Codes 2 – AL.06 to AL.13

AL.06 – Overspeed

AL.06 occurs when the commanded or actual motor speed exceeds the permitted operating range.

Possible cause: Pulse-command frequency is too high
• Check the input frequency of the pulse and direction command.
• Reduce the pulse-command frequency to a value permitted by the servo drive.

Possible cause: Acceleration / deceleration time is too short
• Check the acceleration and deceleration settings.
• Increase the acceleration / deceleration time if the application permits.

Possible cause: Unstable servo tuning
• Check whether the machine continuously oscillates or vibrates.
• Check the servo loop gain settings.
• If gain adjustment does not correct the problem, reduce load inertia or modify the motion profile.

AL.07 – Pulse Control Command Error

AL.07 occurs when the pulse-command input frequency exceeds the permitted value.

Possible cause: Pulse frequency exceeds the rated input frequency
• Measure or verify the pulse signal frequency.
• Compare it with the permissible input frequency of the servo drive.
• PLC applications using high-speed pulse outputs should also be checked for correct output configuration.

Possible cause: Pulse-command device fault
• Check the PLC, motion controller or other pulse-command source.
• Replace or repair the command device if its output signal is abnormal.

AL.08 – Excessive Position Control Error

AL.08 occurs when the position-control error exceeds the permitted value.

Possible cause: Acceleration / deceleration time is too short
• Check the motion profile and acceleration / deceleration settings.
• Increase the time constants if necessary.

Possible cause: Torque limit is too low
• Check torque-limit parameter PA05.
• If suitable for the motor and mechanical system, increase the torque limit.

Possible cause: Position-loop gain is too low
• Check parameter PB07.
• Adjust the position-loop gain according to the machine response.

Possible cause: Mechanical load is too high
• Check the external load and mechanical resistance.
• Reduce the load or reassess the servo motor and drive capacity.

AL.09 – Serial Communication Error

AL.09 indicates abnormal RS232 / RS485 communication.

Possible cause: Communication settings do not match
• Check the communication protocol, baud rate, data format and related parameters.
• Make sure the host controller and servo drive use matching communication settings.

Possible cause: Incorrect communication address
• Check the servo-drive station address.
• Make sure the host controller is communicating with the correct device address.

Possible cause: Invalid communication data
• Check command values, register addresses and transmitted data.
• Correct any invalid or unsupported access values.

AL.0A – Serial Communication Timeout

AL.0A occurs when valid communication is not received within the specified timeout period.

Possible cause: Communication line interrupted
• Check the RS485 / Modbus communication cable for loose terminals, broken conductors or incorrect wiring.
• Repair or replace the communication cable as required.

Possible cause: Timeout setting is incorrect
• Check the communication timeout parameter.
• Adjust the timeout according to the controller and application requirements.

AL.0B – Position Detector / Encoder Error 1

AL.0B occurs when the servo drive detects an abnormal position-feedback pulse signal.

Possible cause: Incorrect encoder connection
• Check the wiring of the position encoder.
• Make sure the encoder cable is connected according to the servo manual.

Possible cause: Loose encoder connector
• Check the encoder connector and cable connection.
• Reconnect and secure the connector correctly.

Possible cause: Encoder failure
• Check the rotary encoder and feedback signal.
• If the encoder is integrated into the servo motor and is defective, motor service or replacement may be required.

AL.0C – Position Detector / Encoder Error 2

AL.0C indicates an abnormal condition associated with the servo motor encoder or its initial magnetic-field detection.

• Check the motor and encoder connections.
• Check that the motor shaft can rotate freely before restarting the system.
• If the alarm remains, the servo motor or encoder system may require service inspection.

AL.0D – Servo Drive Cooling Fan Error

AL.0D occurs when the servo-drive cooling fan stops or operates abnormally.

• Safely switch off the servo-drive power supply.
• Check whether foreign material is preventing the fan from rotating.
• Check the fan cable and connector.
• Replace the cooling fan if defective.
• If the fault remains, service inspection may be required.

AL.0E – IGBT Overtemperature

AL.0E indicates excessive temperature in the servo-drive power stage.

Possible cause: Excessive load or output short circuit
• Check whether the servo system is operating above its rated load.
• Check whether the motor current is abnormally high.
• Check the drive output wiring for a short circuit.
• Reduce the mechanical load or select a higher-capacity servo system if required.

AL.0F – Memory / EEPROM Error

AL.0F indicates abnormal access to the servo drive's EEPROM memory. The alarm may occur during memory read or write operations.

• Power the servo drive down and restart it after the required discharge time.
• If appropriate, consider restoring factory parameters.
• Back up important parameter settings before performing a factory reset.
• If the fault remains, the EEPROM or control circuitry may require service inspection.

AL.10 – Overload 2

AL.10 may occur when mechanical impact or sudden loading causes excessive motor current to continue for too long.

Possible cause: Incorrect motion profile or mechanical impact
• Check the path and motion profile.
• Correct the motion curve where necessary.
• Use an appropriate limit switch where mechanical travel must be restricted.

Possible cause: Motor connection error
• Check the servo motor wiring and connectors.
• Correct any wiring error before restarting the system.

Possible cause: System vibration
• Check the machine for high-frequency vibration or resonance.
• Reduce excessively aggressive servo tuning.
• If necessary, retune the system or use the applicable servo Auto Tune function.

Possible cause: Encoder failure
• Check the encoder signal and cable.
• If the encoder is integrated into the motor and has failed, servo motor service or replacement may be required.

AL.11 – Motor Matching Error

AL.11 indicates that the connected servo motor and servo drive are not recognized as a compatible combination.

• Check the servo motor and drive model numbers.
• Confirm that motor capacity and drive capacity are compatible.
• Use the correct motor / drive combination specified for the servo system.

AL.12 – Emergency Stop

AL.12 is displayed when the emergency-stop input is active.

• Check the emergency-stop button and related safety circuit.
• Identify and remove the condition that required the emergency stop.
• Reset the alarm only after the machine is safe to operate.

AL.13 – Forward / Reverse Travel Limit Warning

AL.13 occurs when the forward or reverse travel-limit input becomes active.

• Check the physical position of the forward and reverse limit switches.
• Check the wiring and input status of both limit switches.
• If the axis has reached a mechanical travel limit, return it safely to the permitted operating range.
• Replace or repair a defective limit switch or connection.

Shihlin Servo Fault Codes
Shihlin Servo Fault Codes 1 – AL.01 to AL.05 | Shihlin Servo Fault Codes 2 – AL.06 to AL.13

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