O B J E C T I V E S After studying this chapter, you will be able to: • • Identify five types of single-phase induction motors. • • Describe the operation and application of induction motors. • • Demonstrate how to make proper motor connections. • • Use an ohmmeter to identify hermetic compressor terminals. • •• Troubleshoot induction motor problems. •• Select and connect start components. • Identify examples of multi-speed and dual- voltage motors. • •• Describe the operation and application of ECMs. • Select and install proper fan replacements. I M P O R T A N T T E R M S multi-speed motor open capacitor open winding permanent split- capacitor (PSC) motor plates poles revolutions per minute (rpm) rotation run capacitor run winding shaded-pole motor shading coil shaft end short cycle shorted capacitor shorted to ground shorted winding single-phasing slip split-phase motor squirrel cage rotor start capacitor start winding synchronous speed taps torque unload VAC zerk fitting 25.1 Induction-Type Motors Electric motors of the induction type are common in refrigeration, heating, and air condi- tioning applications where they are used to drive compressors, fans, pumps, and other devices. Since a motor malfunction causes severe system problems, the technician must possess a good working knowledge of motors and their operation to properly troubleshoot a system and perform necessary repairs. Sometimes, the motor malfunc- tion is a warning of other system problems that must be identified and solved. There are six basic types of induction motors: five single-phase and one three-phase. Although methods of operation are similar, each type of induction motor serves a unique purpose. It is sometimes necessary to convert from one type of motor to another to achieve better operating characteristics. Motors CHAPTER 25 arcing axial bearing bimetallic bleed resistor bushing capacitor capacitor-start, capacitor-run (CSCR) motor capacitor-start, induction-run (CSIR) motor centrifugal centrifugal switch common cycling on the overload dielectric dual-voltage motor electronically commu- tated motor (ECM) electrodes fractional horsepower full load amperage (FLA) hard start kit induced magnetism integral horsepower laminated lead end locked rotor amperage (LRA) microfarads motor overload protector 485 Copyright Goodheart-Willcox Co., Inc.