The type of motor controller that can automatically open and close circuits when its coil is energized is called a contactor. A contactor is an electromechanical device that consists of an electrical coil and a set of contacts. When the coil is energized, it creates a magnetic field that attracts the contacts, causing them to close and complete an electrical circuit. Conversely, when the coil is de-energized, the contacts spring back to their original position, opening the circuit. This automatic opening and closing of circuits makes contactors suitable for various applications, such as controlling motors, lighting systems, and other electrical loads.
