Pressure switches – Troubleshooting and repair
A pressure switch is a type of switch that operates an electrical contact when a certain defined fluid pressure has been reached at its input. The switch can be designed to make contact either on increasing pressure or decreasing pressure. Pressure switches are widely used in industry to automatically monitor and control systems that use fluids under pressure.
Another type of pressure switch detects mechanical force; for example, a pressure-sensitive mat is used to automatically open doors in commercial buildings. Such sensors are also used in security alarm applications such as pressure sensitive floors.
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Electric Motors and Drives: Fundamentals, Types and Applications
Best-selling reference book on electric motors and drives for non-specialists, bridging the gap between mathematics and theory.
Mechanical Design of Electric Motors
Rapid increases in energy consumption and emphasis on environmental protection have posed challenges to the motor industry, as has the design and manufacture of highly efficient, reliable, economical, energy-saving, quiet, precisely controlled and durable electric motors.
Suitable for motor designers, engineers, manufacturers, as well as maintenance personnel, undergraduate and graduate students, and researchers in academia, Mechanical Design of Electric Motors provides in-depth knowledge of modern design methods and developments in electric motors. From motor classification, motor component design, model configuration and selection of materials and bearings, to power losses, motor cooling, design integration, vibration and acoustic noise, this comprehensive text covers the fundamentals, practical design and design issues, modeling and simulation, engineering analysis, manufacturing processes, test procedures and performance characteristics of today's electric motors.
Focusing on the mechanical design of modern electric motors, the book:
Details the design and manufacturing of major components and subsystems, such as rotors, shafts, stators and frames
Examines various cooling techniques, including forced air, liquid, and phase change
Discusses the analysis and calculation of engine power losses
Addresses engine vibration and acoustic noise issues
Presents technical analysis methods and case study results
Highlights construction, optimization and applications
Featuring research findings from the author's personal experience and important contributions from others, Mechanical Design of Electric Motors highlights innovative and advanced electric motors developed over the past decades.
Mechanical Design of Electric Motors
The importance of electric motors is well known in various fields of engineering. The book provides comprehensive coverage of different types of electric motors, including DC motors, three-phase and single-phase induction motors, synchronous motors, universal motor, AC servo motor, linear induction motor, and stepper motors. The book covers all details of DC motors, including torque equation, back EMF, characteristics, types of starters, speed control methods and applications.
The book also covers the different methods of testing DC motors such as Swinburne test, brake test, idle test, field test and Hopkinson test. The book further explains three-phase induction motors in detail. It includes production of rotating magnetic field, construction, operation, effect of slip, torque equation, torque ratios, torque-slip characteristics, losses, power flow, equivalent circuit, effect of harmonics on performance, pie chart and applications. This chapter also includes the discussion of induction generator. The book teaches the various methods of starting and speed controlling three-phase induction motors. The book incorporates the explanation of different single-phase induction motors. The chapter on synchronous motor provides a detailed discussion on construction, principle of operation, on-load behavior, phasor diagram analysis, V-shaped and inverted-V curves, hunting, synchronous capacitor and applications. The book also teaches the different special machines such as single phase commutator motors, universal motor, AC servo motor, linear induction motor and stepper motors. The book uses clear and lucid language to explain each topic. The book provides the logical method of explaining different complicated topics and step by step methods to make understanding easy. Each chapter is well supported by necessary illustrations, self-explanatory diagrams, and a variety of solved problems. The book explains the philosophy of the subject which makes the understanding of the concepts very clear and makes the subject more interesting.
Motor Starting and Control Primer: An introduction to the starting techniques and control of electric motors
Whether you're a busy electrical engineer who needs to refresh your memory on starting motors, a time-poor student new to the subject, or an interested person who has an hour to spare, this book is the perfect place to start. Steven McFadyen shares his expertise in starting engines in a clear and easily accessible manner, without time-consuming verbiage or self-sufficient discussions. Complete with circuit diagrams and in-depth explanations of the most common motor starting methods and related challenges, this book is a valuable reference. It offers something for anyone who wants to learn new things, while helping practicing electrical engineers design and implement reliable and functional motor starters.
