What is the difference between a motor starter and a motor controller?

A motor starter and a motor controller serve different purposes in electric motor systems. A motor starter is primarily designed to start and stop a motor. It provides the necessary electrical connections to energize the motor, ensuring safe operations at startup. A typical motor starter may include protections against overcurrent but does not typically offer functionalities that modify the motor's operation once it has started.

On the other hand, a motor controller encompasses broader functionalities than just starting or stopping a motor. It may include features such as speed control, direction control, soft starting, and even more advanced options like torque control and position control. Controllers are incorporated into systems where the operational requirements go beyond simple starting and stopping, allowing for various adjustments in the motor's performance based on the specific application needs.

Thus, the distinction lies in the functionality: while the starter focuses on initiation and protection of the motor, the controller allows for greater management and versatility in how the motor operates throughout its service.