Electric Motor free essay sample

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Printed in the United States of America 1 2 3 4 5 XX 11 10 09 Contents Preface vi Section 1 Introduction 1 UNIT 1 General Principles of Electric Motor Control 3 UNIT 2 Fractional and Integral Horsepower Manual Motor Starters 17 UNIT 3 Magnetic Line Voltage Starters 23 Section 2 Circuit Layout, Connections, and Symbols UNIT 4 Symbols 51 UNIT 5 49 Interpretation and Application of Simple Wiring and Elementary Diagrams 63 Section 3 Control Pilot Devices UNIT 6 Push Buttons and Control Stations 81 UNIT 7 Relays 87 UNIT 8 Contactors 95 UNIT 9 Timing Relays 103 UNIT 10 Pressure Switches and Regulators 113 UNIT 11 Float Switches 117 UNIT 12 Flow Switches 123 UNIT 13 Limit Switches and Proximity Control 127 UNIT 14 Phase Failure Relays 135 UNIT 15 Solenoid Valves 139 UNIT 16 79 Temperature Switches 143 Section 4 Basic Control Circuits UNIT 17 Two-Wire Controls 149 UNIT 18 Three-Wire and Separate Controls 153 UNIT 19 Hand-Off Automatic Controls 159 UNIT 20 Multiple Push-Button Stations 163 UNIT 21 Interlocking Methods for Reversing Control 165 UNIT 22 Sequence Control 173 UNIT 23 Jogging (Inching) Control Circuits 181 UNIT 24 147 Time-Delay, Low-Voltage Release Relay 187 v Section 5 AC Reduced Voltage Starters UNIT 25 The Motor and Starting Methods 193 UNIT 26 Primary Resistor-Type Starters 199 UNIT 27 Autotransformer Starters 205 UNIT 28 Part Winding Motor Starters 211 UNIT 29 Automatic Starters for Star-Delta Motors 217 UNIT 30 AC Solid-State Reduced Voltage Controller 223 Section 6 Three-Phase, Multispeed Controllers UNIT 31 Two-Speed, One-Winding (Consequent Pole) Motor Controller 239 UNIT 33 31 Controllers for Two-Speed,Two-Winding (Separate Winding) Motors 233 UNIT 32 Four-Speed,Two-Winding (Consequent Pole) Motor Controller 247 Section 7 Wound Rotor (Slip Ring) Motor Controllers UNIT 34 Push-Button Speed Selection 261 UNIT 36 Automatic Acceleration for Wound Rotor Motors 263 UNIT 37 Automatic Speed Control for Wound Rotor Motors 269 UNIT 38 253 Wound Rotor Motors and Ma nual Speed Control 255 UNIT 35 Solid-State Adjustable Speed Controller for AC Wound Rotor Motors 275 Section 8 Synchronous Motor Controls UNIT 39 Push-Button Synchronizing 287 UNIT 41 Timed Semiautomatic Synchronizing 291 The textbook discusses electrical and mechanical components and how they are connected to control different types of motors. Many different types of control circuit and illustrations are discussed. The text contains a wealth of practical information that will apply to almost any industrial application. Â  The text assumes that students have knowledge of basic electrical theory and common series and parallel circuits. Electric Motor Control has been used successfully for both formal classroom training and self study. It is used extensively in preapprentice and indentured apprentice training programs and n organized journeyman electrician classes. The practical approach to motor control makes this a very useful handbook on the job for installing, monitoring, and maintaining control systems. Electric Motor Control provides a very practical approach to a somewhat dif? cult subject. The text is written in easy-to-understand language. Each unit of instruction covers a short, concise topic . Expected student learning is outlined in the objectives at the beginning of each unit. The appendices and glossary provide further explanation of terms and servicing to troubleshooting, which the student is encouraged to use. The ninth edition contains expanded information on overload relays and numerous updated illustrations. The text employs a second color to highlight important concepts. The ninth edition provides an update to a textbook that has long been regarded as an outstanding book on the subject of motor control theory and practical application. Electric Motor Control illustrates control systems, starting with the simplest of equipment, and builds on it in a step-by-step fashion to more complex circuits. Students learn to draw and interpret motor control schematics and wiring diagrams.