Common fault causes and solutions for servo drives

1. The LED light is green, but the motor does not move

(1) Cause of failure: The motor in one or more directions is prohibited from operating.

Solution: Check the +INHIBIT and –INHIBIT ports.

(2) Cause of failure: The command signal is not to the driver signal.

Solution: Connect the command signal ground to the drive signal ground.

2. After powering on, the LED light of the driver does not light up

Cause of failure: The power supply voltage is too low, less than the minimum voltage value requirement.

Solution: Check and increase the supply voltage.

3. When the motor rotates, the LED light flashes

(1) Fault cause: HALL phase error.

Solution: Check whether the phase setting switch of the motor is correct.

(2) Cause of failure: HALL sensor failure.

Solution: Detect the voltage of HallA, HallB, and HallC when the motor is rotating. The voltage value should be between 5VDC and 0.

4. The LED light is always kept red

Fault Cause: A fault exists.

Solution: Cause: Overvoltage, Undervoltage, Short Circuit, Overheating, Driver Prohibition, HALL Invalid.

5. The motor stalls

(1) Cause of failure: The polarity of the speed feedback is wrong.

Solution:

a. If possible, hit the position feedback polarity switch to another position. (Yes on some drives)

b. If using a speed tester, switch the TACH+ and TACH- on the drive.

c. If an encoder is used, switch the ENCA-ENCB and ENCB on the drive.

d. If in HALL speed mode, switch HALL-1 and HALL-3 on the drive, and then switch Motor-A and Motor-B.

(2) Cause of failure: When the encoder speed feedback, the encoder power supply loses power.

Solution: Check that the 5V encoder power supply is connected. Make sure that the power supply can provide enough current. If using an external power supply, make sure that the voltage is signaled to ground for the driver.

6. The motor runs faster in one direction than the other

(1) Cause of failure: The phase of the brushless motor is wrong.

Solution: Detect or detect the correct phase.

(2) Cause of failure: When not used for testing, the test/deviation switch hits the test position.

Solution: Put the test/deviation switch at the deviation position.

(3) Cause of failure: The position of the deviation potentiometer is incorrect.

Solution: Reset.

7. When the oscilloscope checks the current monitoring output of the driver, it is found that it is all noise and cannot be read

Cause of failure: The current monitoring output is not isolated from the AC power supply (transformer).

Solution: It can be detected and observed with a DC voltmeter.

8. How to deal with the motor deviation counter overflow error when the servo motor rotates at high speed?

(1) Cause of failure: motor deviation counter overflow error occurs when rotating at high speed;

Solution: Check whether the wiring of the motor power cable and encoder cable is correct, and whether the cable is damaged.

(2) Cause of failure: motor deviation counter overflow error occurs when long instruction pulse is input;

Solution: a. If the gain setting is too large, adjust the gain manually again or use the automatic gain adjustment function;

b. Extend the acceleration and deceleration time;

c. If the load is too heavy, it is necessary to re-select a motor with a larger capacity or reduce the load, and install a reducer and other transmission mechanisms to improve the load capacity.

(3) Cause of failure: motor deviation counter overflow error occurs during operation.

Solution: a. Increase the set value of the overflow level of the deviation counter;

b. Slow down the rotation;

c. Extend the acceleration and deceleration time;

d. If the load is too heavy, it is necessary to re-select a motor with a larger capacity or reduce the load, and install a reducer and other transmission mechanisms to improve the load capacity.

9. How to deal with the servo motor not running when there is pulse output?

(1) Monitor the current value of the pulse output of the controller and whether the pulse output light is flashing, and confirm that the command pulse has been executed and the pulse has been output normally;

(2) Check whether the control cable, power cable and encoder cable from the controller to the driver are wired incorrectly, damaged or in poor contact;

(3) Check whether the brake of the servo motor with brake has been opened;

(4) Monitor the panel of the servo driver to confirm whether the pulse command is input;

(5) The Run command is normal;

(6) The control mode must be selected as the position control mode;

(7) Whether the input pulse type set by the servo drive is consistent with the setting of the instruction pulse;

(8) Make sure that the forward side drive is inhibited, the reverse side drive inhibition signal and the deviation counter reset signal are not entered, the load is disconnected and the no-load operation is normal, and the mechanical system is checked.

Common fault causes and solutions for servo drives

Common fault causes and solutions for servo drives

Sections viewed

Contact

working hours