2nd Edition

Electrical Contacts Principles and Applications, Second Edition

Edited By Paul G. Slade Copyright 2014
    1312 Pages 881 B/W Illustrations
    by CRC Press

    1311 Pages 881 B/W Illustrations
    by CRC Press

    Covering the theory, application, and testing of contact materials, Electrical Contacts: Principles and Applications, Second Edition introduces a thorough discussion on making electric contact and contact interface conduction; presents a general outline of, and measurement techniques for, important corrosion mechanisms; considers the results of contact wear when plug-in connections are made and broken; investigates the effect of thin noble metal plating on electronic connections; and relates crucial considerations for making high- and low-power contact joints. It examines contact use in switching devices, including the interruption of AC and DC circuits with currents in the range 10mA to 100kA and circuits up to 1000V, and describes arc formation between open contacts and between opening contacts. Arcing effects on contacts such as erosion, welding, and contamination are also addressed.

    Containing nearly 3,000 references, tables, equations, figures, drawings, and photographs, the book provides practical examples encompassing everything from electronic circuits to high power circuits, or microamperes to mega amperes. The new edition:

    • Reflects the latest advances in electrical contact science and technology
    • Examines current research on contact corrosion, materials, and switching
    • Includes updates and revisions in each chapter, as well as up-to-date references and new figures and examples throughout
    • Delivers three new chapters on the effects of dust contamination, electronic sensing for switching systems, and contact phenomena for micro-electronic systems (MEMS) applications

    With contributions from recognized experts in the field, Electrical Contacts: Principles and Applications, Second Edition assists practicing scientists and engineers in the prevention of costly system failures, as well as offers a comprehensive introduction to the subject for technology graduate students, by expanding their knowledge of electrical contact phenomena.

    Preface to the Second Edition
    Preface to the First Edition
    Introduction
    Editor
    Contributors
    Contact Interface Conduction
    Electrical Contact Resistance: Fundamental Principles
    Roland S. Timsit
    Introduction
    Electrical Constriction Resistance
    Effect of Surface Films on Constriction and Contact Resistance
    Temperature of an Electrically Heated a-Spot
    Mechanics of a-Spot Formation
    Breakdown of Classical Electrical Contact Theory in Small Contact Spots
    Constriction Resistance at High Frequencies
    Summary
    Acknowledgements
    References
    Introduction to Contact Tarnishing and Corrosion
    Paul G. Slade
    Introduction
    Corrosion Rates
    Corrosion Gases
    Types of Corrosion
    Gas Concentrations in the Atmosphere
    Measurements
    Mixed Flow Gas Laboratory Testing
    Electronic Connectors
    Power Connectors
    Other Considerations
    Acknowledgements
    References
    Gas Corrosion
    William H. Abbott and Paul G. Slade
    Introduction
    The Field Environments for Electrical Contacts
    Laboratory Accelerated Testing
    Lubrication and Inhibition of Corrosion
    Acknowledgement
    References
    Effect of Dust Contamination on Electrical Contacts
    Ji Gao Zhang
    Introduction
    Dusty Environment and Dust Composition
    The Characteristics of Dust Particles
    Application Conditions in Dusty Environment
    Theoretical Analysis of Connector Contact Failure due to the Dust
    Future Work
    References
    Nonarcing Contacts
    Power Connectors
    Milenko Braunovic
    Introduction
    Types of Power Connectors
    Properties of Conductor and Connector Materials
    Parameters Affecting Performance of Power Connections
    Palliative Measures
    Connector Degradation
    Prognostic Models
    Shape-Memory Alloys (SMA)
    Metal Foam Materials
    Installation of Power Connections
    Accelerated Current-Cycling Tests (Standards)
    References
    Low-Power Commercial, Automotive, and Appliance Connections
    Anthony Lee and George Drew
    Introduction
    Connectors
    Contact Terminals
    Degradation of Connector Contact
    Automotive Connector Contacts
    Summary
    References
    Tribology of Electronic Connectors: Contact Sliding Wear, Fretting, and Lubrication
    Roland S. Timsit and Morton Antler
    Introduction
    Sliding Wear
    Fretting
    Lubrication
    References
    Materials, Coatings, and Platings
    Morton Antler and Paul G. Slade
    Introduction
    Metallic Finishes
    Properties Related to Porosity
    Metallurgical and Structural Properties
    Physical and Mechanical Properties
    Acknowledgement
    References
    The Electric Arc and Switching Device Technology
    The Arc and Interruption
    Paul G. Slade
    Introduction
    The Fourth State of Matter
    Establishing an Arc
    The Formation of the Electric Arc
    The Arc in Air at Atmospheric Pressure
    The Arc in Vacuum
    Arc Interruption
    Acknowledgements
    References
    The Consequences of Arcing
    Paul G. Slade
    Introduction
    Arcing Time
    Arc Erosion of Electrical Contacts
    Blow-Off Force
    Contact Welding
    Changes in the Contact Surface as a Result of Arcing
    Acknowledgements
    References
    Reed Switches
    Kunio Hinohara
    Principles and Design of the Reed Switch
    Recommended Contact Plating
    Contact Surface Degradation and Countermeasures
    Applications of Reed Switches
    References
    Low Current and High Frequency Miniature Switches: Microelectromechanical Systems (MEMS) Metal Contact Switches
    Benjamin F. Toler, Ronald A. Coutu, Jr., and John W. McBride
    Introduction
    Micro-Contact Resistance Modeling
    Contact Materials for Performance and Reliability
    Failure Modes and Reliability
    Conclusion
    References
    Low Current Switching
    John W. McBride
    Introduction and Device Classification
    Device Types
    Design Parameters for Static Switching Contacts
    Mechanical Design Parameters
    The Measurement of Contact Wear and Contact Dynamics
    Electrical Characteristics of Low-Current Switching Devices at Opening
    Electrical Characteristics of Low-Current Switching Devices at Closure
    Summary
    Acknowledgements
    References
    Medium to High Current Switching: Low Voltage Contractors and Circuit Breakers, and Vacuum Interrupters
    Manfred Lindmayer
    General Aspects of Switching in Air
    Contacts for Switching in Air
    Low-Voltage Contactors
    Low-Voltage Circuit-Breakers and Miniature Circuit-Breakers
    Simulations of Low-Voltage Switching Devices
    Vacuum Interrupters
    References
    Arc Faults and Electrical Safety
    John J. Shea
    Introduction
    Arc Fault Circuit Interrupters (AFCIs)
    Arcing Faults
    Glowing Connections
    Arcing Fault Properties
    Other Types of Arcing Faults
    Conclusions
    References
    Arcing Contact Materials
    Arcing Contact Materials
    Gerald J. Witter
    Introduction
    Silver Metal Oxides
    Silver Refractory Metals
    Vacuum Interrupter Materials
    Tungsten Contacts
    Non-Noble Silver Alloys
    Silver-Nickel Contact Materials
    Silver Alloys and Noble Metals
    Silver-Graphite Contact Materials
    Conclusion
    Acknowledgements
    References
    Contact Design and Attachment
    Gerald J. Witter and Guenther Horn
    Introduction
    Staked Contact Assembly Designs
    Welded Contact Assembly Designs
    Brazed Contact Assembly Designs
    Clad Metals, Inlay, and Edge Lay
    Contact Alloys for Non-Arcing Separable Contacts
    Acknowledgements
    References
    Electrical Contact Material Testing Design and Measurement
    Gerald J. Witter and Werner Rieder
    Objectives
    Device Testing and Model Switch Testing
    Electrical Contact Testing Variables
    Electrical Testing Result Types and Measurement Methods
    References
    Arc Interactions with Contaminants
    Gerald J. Witter and Werner Rieder
    Introduction
    Organic Contamination and Activation
    Mineral Particulate Contamination of Arcing Contacts
    Silicone Contamination of Arcing Contacts
    Lubricants with Refractory Fillers
    Oxidation of Contact Materials
    Resistance Effects from Long Arcs
    Acknowledgements
    References
    Sliding Electrical Contacts
    Sliding Electrical Contacts (Graphitic Type Lubrication)
    Kiochiro Sawa and Erle I. Shobert II
    Introduction
    Mechanical Aspects
    Chemical Aspects
    Electrical Effects
    Thermal Effects
    Brush Wear
    Brush Materials and Abrasion
    Summary
    References
    Illustrative Modern Brush Applications
    Wilferd E. Yohe and William A. Nystrom
    Introduction
    Brush Materials
    Brush Applications
    Sliding Contacts for Instrumentation and Control
    Glenn Dorsey and Jax Glossbrenner
    Introduction
    Sliding Contact—The Micro Perspective
    Electrical Performance
    Micro-Environment of Contact Region
    Macro Sliding Contact
    Materials for Sliding Contacts
    Friction and Wear Characteristics
    Contact Parameters and Sliding-Contact Assemblies
    Future
    Summary
    Acknowledgements
    References
    Metal Fiber Brushes
    Glenn Dorsey and Doris Kuhlmann-Wilsdorf
    Introduction
    Sliding Wear of Multi-Fiber Brushes
    Surface Films, Friction, and Materials Properties
    Electrical Contact
    Brush Dynamics
    Future
    Summary
    Acknowledgements
    References
    Contact Data
    Useful Electric Contact Information
    Paul G. Slade
    Introduction
    Notes to the Tables
    References
    Author Index
    Subject Index

    Biography

    Paul G. Slade began his studies in the fascinating world of electrical contacts as a graduate student at the University of Wales, Cardiff, UK in the mid-1960s. Since that time, he has been involved with electrical contacts both as a research scientist and as a developer of switching components. Currently retired, he ended his five decades of experience in electrical contact research first at the Westinghouse R &D Center, Pittsburgh, Pennsylvania, USA, and then at the Eaton Corporation’s Vacuum Interrupter Factory, Horseheads, New York, USA.

    "This is the book you want to own if you design or test electrical connectors or develop devices using switching or arcing contacts. … It provides the most comprehensive coverage of electrical contact theory, material selection, and switch design of any book on the market today, covering almost all electrical contacts below 1,000 V and some vacuum interrupter technology operating above 1,000 V."
    —John J. Shea, Eaton Corporation, Moon Township, Pennsylvania, USA, from IEEE Electrical Insulation Magazine, May/June 2015