Is a Robot Servo Drive Alarm Always Indicative of a Faulty Drive? Judging Motor, Cable, and Load

When a robot experiences overcurrent, position deviation, encoder, overvoltage, or enable failure alarms, the fact that the alarm is detected by the drive does not necessarily mean the drive unit itself is damaged. Before repair, one should distinguish between the drive module, servo motor, feedback loop, and mechanical load to avoid replacing parts only for the fault to persist.

1. Analyze the Alarm and Occurrence Conditions

Record the complete code, associated axis, occurrence speed, direction, posture, and load. Alarms occurring immediately upon power-up, after movement, during commutation, or after temperature rise correspond to different inspection sequences.

1. Check the Motor and Cables

Check the power cables, feedback cables, connectors, shielding, and grounding. When measuring the three-phase status and insulation of the motor, isolate the drive and use methods compliant with the motor and encoder requirements to prevent test voltage from damaging feedback devices.

1. Check the Brake and Mechanical Load

Incomplete brake release, gearbox binding, bearing damage, or external collisions can all cause increased axis current. During low-speed single-axis testing, observe for abnormal noise, vibration, temperature rise, and load variations in different directions.

1. Check the Drive and Common Circuits

When multiple axes alarm simultaneously, prioritize checking the common power supply, DC bus, and internal communication. After confirming a drive module fault, verify the model and version, and after replacement, complete parameter, low-speed, loaded, and continuous operation verification.

The correct way to handle a servo alarm is to follow a complete diagnostic chain from the drive, cables, motor, brake, to the mechanical load, rather than replacing the drive based solely on the alarm name.

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Contact Repair Engineer: +86 18122009539