Pressure switches – Troubleshooting and repair
A pressure switch is a type of switch that actuates an electrical contact when a certain preset fluid pressure has been reached at its inlet. The switch can be designed to make contact on both pressure rise and pressure drop. Pressure switches are widely used in industry to automatically supervise and control systems that use pressurized fluids.
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.
For more information about pressure switches
Pressure switches on Wikipedia
See all pressure switches in the Unitec catalogue
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Electric Motors and Drives: Fundamentals, Types and Applications
Best-selling reference on Electric Motors and Drives for non-experts, 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, economically viable, energy-efficient, quiet, precisely controlled and durable electric motors.
Suitable for motor designers, engineers and manufacturers, as well as maintenance personnel, undergraduate and postgraduate students and academic researchers, Mechanical Design of Electric Motors provides in-depth knowledge of state-of-the-art design methods and electric motor developments. From motor classification, motor component design, model configuration, and material and bearing selections to energy losses, motor cooling, design integration, vibration, and acoustic noise, this comprehensive text covers the fundamentals, practical design, and issues related to the design, modeling and simulation, engineering analysis, manufacturing processes, test procedures, and performance characteristics of electric motors today.
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 structures
Examines various cooling techniques, including forced air, liquid, and phase change
Discusses the analysis and calculation of engine energy losses
Addresses engine vibration and acoustic noise issues
Presents engineering analysis methods and case study results
Emphasizes construction, optimization and applications
Featuring research findings from the author's own personal experience and the significant contributions of others, Mechanical Design of Electric Motors highlights innovative and advanced electric motors developed over the past few decades.
Mechanical Design of Electric Motors
The importance of electric motors is well known in the various fields of engineering. The book provides comprehensive coverage of the various types of electric motors, including d.c. motors, three-phase and single-phase induction motors, synchronous motors, universal motor, a.c. servo motor, linear induction motor, and stepper motors. The book covers all details of d.c. motors including torque equation, e.m.f. reverse, characteristics, types of starts, speed control methods and applications.
The book also covers the various testing methods of d.c. motors such as Swinburne test, brake test, deceleration test, field test and Hopkinson test. The book also explains three-phase induction motors in detail. Includes rotating magnetic field production, construction, functioning, slip effect, torque equation, torque ratios, torque-slip characteristics, losses, energy flow, equivalent circuit, effect of harmonics on performance, circle diagram and applications. This chapter also includes discussion of the induction generator. The book teaches the various starting methods and speed control methods of three-phase induction motors. The book incorporates the explanation of various single-phase induction motors. The chapter on synchronous motor provides detailed discussion of construction, working principle, load behavior, phasor diagram analysis, Vee and inverted Vee curves, oscillation, synchronous capacitor and applications. The book also teaches the various special machines like single phase commutator motors, universal motor, ac servo motor, linear induction motor and stepper motors. The book uses clear, lucid language to explain each topic. The book provides the logical method of explaining the various complicated topics and step by step methods for easy understanding. Each chapter is well supported with necessary illustrations, self-explanatory diagrams and variety of solved problems. The book explains the philosophy of the subject, which makes understanding 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 needing a refresher on motor starting, a time-strapped student new to the subject, or an interested person with an hour to spare, this book is the place to start. Steven McFadyen shares his expert engine starting knowledge in a clear, easily accessible way, without unnecessary verbiage or self-promoting discussions. Complete with circuit diagrams and thorough explanations of the most common motor starting methods – and challenges – this book is an invaluable reference. It has something to offer anyone interested in learning new things, while also helping working electrical engineers design and implement reliable and functional motor starters.
