Servo drive common failure analysis
1.when the servo motor is in high-speed rotation,occurs motor deviation counter overflow error, how to deal with?
① Motor deviation counter overflow error during high speed rotation;
Countermeasure:Check motor power cable and encoder cable whether are wired correctly,or cable is damaged.
② When the longer command pulse is inputing,the motor deviation counter overflow error occurs.
A. The gain setting is too large, re-adjust the gain manually or use the auto-adjust gain function;
B. Extend the acceleration / deceleration time;
C. Heavy load, need to re-select the larger capacity motor or reduce the load,add reducer and other transmission agencies to improve load capacity.
③ A motor deviation counter overflow error during operation.
A. Increase the deviation counter overflow level setting value;
B. Slow down the rotation speed;
C. Extend the acceleration / deceleration time;
D. Heavy load, need to re-select the larger capacity motor or reduce the load,add reducer and other transmission agencies to improve the load
2,the servo motor does not run when pulse output,how to deal with?
(1) monitor pulse output current value of the controller and whether the pulse output led is flashing, confirm that the command pulse has been executed and the pulse has been output normally;
② check the controller to the drive control cable, power cable, encoder cable wiring,wrong,broken or poor contact;
③ check the brake motor's brake has been opened;
④ monitor the servo drive panel to confirm whether the pulse input;
⑤ Run command is normal;
⑥ control mode must choose the position control mode;
⑦ Whether the input pulse type set by the servo driver and the command pulse setting are the same;
⑧ Make sure that the forward drive side is disabled, the reverse side drive inhibit signal, and the deviation counter reset signal are not input, the load is disengaged and empty load operation is normal, check the mechanical system.
3,the servo motor is empty loaded but alarm overload, how to deal with?
① in the case of the servo Run (run) signal access and no pulse occurred:
A. Check the servo motor power cable wiring,bad contact or cable breakage;
B. If the servo motor is equipped with a brake,make sure that brake opened;
C. Whether the speed loop gain set too high;
D. Whether the integral time constant of the speed loop set too small.
② if happens in the process of running:
A. Position loop gain set too large;
B. Whether the positioning completion amplitude set too small;
C. Check that there is no stall on the servo motor shaft and re-adjust the machine.
4,the servo motor has abnormal sound or jitter phenomenon in running,how to deal with?
① servo wiring:
A. Use standard power cable,encoder cable,control cable,cable whether damaged;
B. Check whether there is interference source near the control cable and whether it is too close or paralle with each other of large current power cable;
C. Check whether the ground terminal potential has changed, and ensure that the ground is good.
② servo parameters:
A. Servo gain setting is too large, it is recommended to manually or automatically re-adjust the servo parameters;
B. Confirm the speed feedback filter time constant setting, the initial value is 0, try to increase the setting value;
C. Electronic gear ratio setting is too large,recommend return to factory settings;
D. Resonance of the servo system and the mechanical system,try to adjust the notch filter frequency and amplitude.
③ mechanical system:
A. The coupling of the motor shaft and the equipment system is offset and the mounting screws are not tightened;
B. Poor engagement of the pulley or gear can also cause the load torque to change, try empty load operation, if empty load operation is normal check the mechanical system combined part;
C. Check the load inertia, torque and speed is too large, try empty load operation, if empty load operation is normal, then reduce the load or replace the larger capacity of the drive and motor.
5.the servo motor location control positioning are not accurate, how to deal with?
① first confirm the current actual pulse value issued by the controller is consistent with the expected, if inconsistent,check and correct the program;
② monitor receiving pulse instructions counts of the servo drive whether keep the same as controller issued,if inconsistent,check the control cable;