Main content

Objectives

• After studying this unit, you should be able to
• describe the different types of open single-phase motors used to drive fans, compressors, and pumps.
• describe various types of motor applications.
• state which motors have high starting torque.
• list the components that cause a motor to have a higher starting torque.
• describe a multispeed, permanent, split-capacitor motor and indicate how the different speeds are obtained.
• explain the operation of shaded pole motors.
• explain potential and current motor relays and positive temperature coefficient resistors (PTCRs).
• explain the operation of a three-phase motor.
• describe a motor used for a hermetic compressor.
• explain the motor terminal connections in various compressors.
• describe the different types of compressors that use hermetic motors.
• describe the use of variable-speed motors, inverters, variable frequency drives (VFDs) and electronically commutated motors (ECMs).

Next: Advance to the Learning Center Dashboard and compete the lessons.