Servo drive is used to control a servo motor controller, its role is similar to the role of AC drive inverter, is part of the servo system, mainly used in high-precision positioning system. Generally through the position, speed and torque control of the servo motor in three ways to achieve high-precision positioning of the transmission system, is currently the transmission technology of high-end products. How to test the servo drive maintenance? The following seven major methods of servo drive repair.
1, the oscilloscope checks the driver’s current monitoring output and found that it is all noise, can not read
Fault reason: The current monitoring output is not isolated from the AC source (transformer).
Approach: You can use DC voltmeter detection observation.
2, the motor runs faster in one direction than the other
(1) Cause of failure: brushless motor phase error.
Approach: Detect or detect the correct phase.
(2) Fault reason: When not used in the test, test / deviation switch hit the test position.
Approach: The test / deviation switch hit the deviation position.
(3) Cause of the malfunction: The position of the deviation potentiometer is not correct.
3, the motor stalls
(1) Fault reason: the polarity of speed feedback is wrong.
Approach: You can try the following methods.
A. If possible, switch the position feedback polarity switch to another position. (Some drives can be)
B. If using a tachometer, swap the TACH + and TACH-switches on the drive.
C. If encoder is used, connect ENC A and ENC B on the drive.
D. If the HALL speed mode, the drive on the HALL-1 and HALL-3 on the tune, and then Motor-A and Motor-B swap tune.
(2) Fault reason: Encoder speed feedback, the encoder power loss.
Approach: check the connection 5V encoder power supply. Make sure that the power supply provides enough current. If using an external power supply, make sure that the voltage is at the driver’s signal ground.
4, LED lights are green, but the motor does not move
(1) Fault reason: one or more directions of the motor prohibited action.
Approach: Check + INHIBIT and -INHIBIT port.
(2) Fault reason: The command signal is not on the drive signal ground.
Approach: The command signal and drive signal connected.
5, the power LED, the driver’s LED light does not shine
Fault reason: supply voltage is too low, less than the minimum voltage requirements.
Approach: check and increase the supply voltage.
6, when the motor rotates, the LED light flashes
(1) Fault reason: HALL phase error.
Remedy: Check whether the motor phase setting switch (60 / 120 ) is correct. Most brushless motors are 120 difference.
(2) Fault reason: HALL sensor fault
Remedy: Detect the voltage of Hall A, Hall B and Hall C when the motor rotates. The voltage should be between 5VDC and 0.
7, LED lights always remain red
Fault reason: There is fault.
Remedy: Cause: Overvoltage, undervoltage, short circuit, overheating, drive disabled, HALL is invalid.