How An Industrial Machines Servo Motor Works?

By Author: Repair Zone
Total Articles: 17
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Motor, control board and potentiometer are three major parts of servo motors. The motor uses a set of gears to rotate the potentiometer and the output shaft. Control circuitry monitors the current angle of the servo motor through potentiometer. Servo motor stops when the control circuit detects the correct position.

Servo motors are industrial machine components that require an internal gear-based transmission system and electronic control. They work in a closed loop, measuring the exact position of the motor head. Reasons for the common usage of servo motors include ease of control, high torque, low energy requirements and TTL voltage level control. Servo motors are efficient due to their relatively small size.

Servo motors must not be confused with stepper motors. Servo motors work in a closed loop while stepper motors operate in an open loop. Servo motors have an accurate system for measuring the position and the difference between the actual position and the desired position. Their role is to fix the gap by controlling the motor. Stepper motors are error-prone as they lack the system of internal feedback. Moreover, ...
... stepper motors lose torque in high rotational speeds, whereas servo motors do not.

RC Servo motors are limited to 0-180 degrees of movement and have to be physically and electrically modified. Servo motors operate in various voltage levels. Using the optimum allowed voltage specified for the motor yields the highest torque.

Servo motors have three wires. The brown/black wire has negative voltage supply; the red wire has positive voltage supply, while the yellow/orange/white wire carries the control signal.

Three major parts in servo motors are motor, control board and potentiometer connected to the output shaft. The motor rides on a set of gears to rotate the potentiometer and the output shaft. The potentiometer allows the control circuitry to monitor the current angle of the servo motor. The potentiometer is fed into the servo motor control circuit. When the control circuit detects the correct position, it stops the servo motor. If the angle is not correct, the servo motor will be turned in a certain direction.

Control mechanism of servo motor generates a PWM (pulse width modulation) signal. A dedicated servo controller is recommended for interfacing servo control. This is because generating several PWM signals simultaneously causes a high system load. In a worst case scenario, it may cause a wrong PWM signal generation, resulting in erroneous movement of the motor.

You need to acquire a servo motor with several configuration and feedback options. An advanced motor design would offer a compact footprint with high torque and low inertia, which is ideal for dynamic applications.

There are economical, high performance motors manufactured to maximize torque and minimize size. These are manufactured with a segmented core to optimize stator efficiency and further decrease size.

When it comes to servo motors Allen Bradley, Indramat and Fanuc are some leading manufacturers. You can be pretty much sure of the quality of motors when procuring from these top-of-the-line companies. You also have to take care of roping in seasoned repair companies. Industrial components are bound to gather problems at some point in time and you have to be prepared of the situation.

Companies of the likes of Repair Zone can combine quality of repair with quick response. You will be well advised to do some research and find a repair company that you can trust for assistance.

The writer is associated with Repair Zone that deals in repair and remanufacturing of industrial machine components.