Servo motor six debugging tips

Editor:浙江汇迅骏机电技术有限公司 │ Release Time:2021-10-13 

6 tips for servo motor debugging are as follows:


1.Initialization parameter

Before wiring, initialize the parameters. 

On the control card: choose the control mode; Clear PID parameters to zero; When the control card is powered on, the default enable signal is turned off.  Save this state to ensure that it is the state when the control card is powered on again. 

On the servo motor: set the control mode; Set enable by external control; Gear ratio of encoder signal output; Set the proportional relationship between control signal and motor speed. In general, it is recommended that the maximum design speed of servo operation correspond to 9V control voltage. 



Power off the control card and connect the signal line between the control card and the servo.  The following lines must be connected: analog output line of control card, enable signal line, encoder signal line of servo output. Power on the servo motor and control card (as well as PC) after the cables are correctly connected.  At this time the motor should not move, and can be easily turned by external forces, if not, check the enable signal Settings and wiring.  Rotate the motor with external force, check whether the control card can correctly detect the change of the motor position, otherwise check the wiring and setting of the encoder signal.


3.Try the direction

For a closed loop control system, if the feedback signal is not in the right direction, the result is certainly disastrous.  Turn on the servo enable signal through the control card.  This is where the servo should rotate at a lower speed, which is known as "zero drift". 


There are generally instructions or parameters on the control card to suppress zero drift.  Use this command or parameter to see if the speed and direction of the motor can be controlled by this command (parameter). 


If it cannot be controlled, check the analog cable connection and the parameter setting of control mode.  Confirm to give a positive number, motor positive, encoder count increases; Negative numbers are given, the motor rotates backwards, and the encoder count decreases. 


Do not use this method if the motor is loaded and has limited travel. Do not test for excessive voltage, recommended below 1V.  If the directions are inconsistent, modify the parameters on the control card or motor to make them consistent. 


4.Inhibition of zero drift

In the closed-loop control process, the existence of zero drift will have a certain influence on the control effect, and it is better to restrain it. Use control card or servo to suppress the parameters of zero drift, carefully adjust the speed of the motor to zero. Because zero drift itself also has a certain randomness, so, do not require the motor speed is absolutely zero. 


5.Establish closed loop control

The servo enable signal is released again through the control card, and a small proportional gain is input on the control card. As for how small it is, it is a matter of feeling. If you are really worried, enter the minimum value that the control card can allow. Turn on the enable signal of the control card and servo. At this point, the motor should have been able to move roughly according to the motion command. 


6.Adjusting closed-loop parameters

Fine-tune the control parameters to ensure that the motor moves according to the command of the control card, which is a must to do the work, and this part of the work, more experience, here can only be omitted.