Audel ™ Electrician’s Pocket Manual All New Second Edition Paul Rosenberg Audel ™ Electrician’s Pocket Manual Audel ™ Electrician’s Pocket Manual All New Second Edition Paul Rosenberg Vice President and Executive Publisher: Bob Ipsen Publisher: Joe Wikert Senior Editor: Katie Feltman Developmental Editor: Regina Brooks Editorial Manager: Kathryn A. Malm Production Editor: Angela Smith Text Design & Composition: Wiley Composition Services Copyright © 2003 by Wiley Publishing, Inc. All rights reserved. Copyright © 1997 by Paul Rosenberg. 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Trademarks: Wiley, the Wiley Publishing logo, Audel, and related trade dress are trade- marks or registered trademarks of Wiley in the United States and other countries, and may not be used without written permission. All other trademarks are the property of their respective owners. Wiley Publishing, Inc., is not associated with any product or vendor mentioned in this book. Wiley also publishes its books in a variety of electronic formats. Some content that appears in print may not be available in electronic books. Library of Congress Cataloging-in-Publication Data: 2003110248 ISBN: 0-764-54199-4 Printed in the United States of America 10 9 8 7 6 5 4 3 2 1 Contents Introduction vii 1. Electrical Laws 1 2. Electronic Components and Circuits 18 3. Electrical Drawings 33 4. Motors, Controllers and Circuits 60 5. Generators 89 6. Mechanical Power Transmission 104 7. Electrical Power Distribution 127 8. Grounding 176 9. Contactors and Relays 203 10. Welding 217 11. Transformers 232 12. Circuit Wiring 246 13. Communications Wiring 272 14. Wiring in Hazardous Locations 296 15. Tools and Safety 317 Appendix 330 Index 336 v Introduction In this handbook for electrical installers you will find a great number of directions and suggestions for electrical installa- tions. These should serve to make your work easier, more enjoyable, and better. But first of all, I want to be sure that every reader of this book is exposed to the primary, essential requirements for electrical installations. The use of electricity, especially at common line voltages, is inherently dangerous. When used haphazardly, electricity can lead to electrocution or fire. This danger is what led to the development of the National Electrical Code (NEC), and it is what keeps Underwriter’s Laboratories in business. The first real requirement of the NEC is that all work must be done “in a neat and workmanlike manner.” This means that the installer must be alert, concerned, and well informed. It is critical that you, as the installer of potentially dangerous equipment, maintain a concern for the people who will be operating the systems you install. Because of strict regulations, good training, and fairly good enforcement, electrical accidents are fairly rare. But they do happen, and almost anyone who has been in this business for some time can remember deadly fires that began from a wiring flaw. As the installer, you are responsible for ensuring that the wiring you install in people’s homes and workplaces is safe. Be forewarned that the excuse of “I didn’t know” will not work for you. If you are not sure that an installation is safe, you have no right to connect it. I am not writing this to scare you, but I do want you to remember that electricity can kill; it must be installed by experts. If you are not willing to expend the necessary effort to ensure the safety of your installations, you should look into another trade — one in which you cannot endanger people’s lives. vii viii Introduction But the commitment to excellence has its reward. The people in the electrical trade who work like professionals make a steady living and are almost never out of work. They have a lifelong trade and are generally well compensated. This book is designed to put as much information at your disposal as possible. Where appropriate, we have used italics and other graphic features to help you quickly pick out key phrases and find the sections you are looking for. In addi- tion, we have included a good index that will also help you find things rapidly. Chapters 1 and 2 of this text cover the basic rules of elec- tricity and electronics. They contain enough detail to help you through almost any difficulty that faces you, short of playing electronic design engineer. They will also serve you well as a review text from time to time. Chapter 3 explains all common types of electrical draw- ings, their use and interpretation. This should be very useful on the job site. Chapters 4 and 5 cover the complex requirements for the installation of motors and generators, and Chapters 6 and 7 will guide you in the transmission of both electrical power and mechanical force. Chapter 8 covers the very important safety requirements for grounding. The many drawings in this chapter will serve to clarify the requirements for you. Chapters 9 through 15 cover a variety of topics, such as the installation and operation of contactors and relays, weld- ing methods, transformer installations, circuit wiring, com- munications wiring, wiring in hazardous locations, and tools and safety. Following the text of the book, you will find an Appendix containing technical information and conversion factors. These also should be of value to you on the job. Best wishes, Paul Rosenberg . Audel ™ Electrician’s Pocket Manual All New Second Edition Paul Rosenberg Audel ™ Electrician’s Pocket Manual Audel ™ Electrician’s Pocket Manual All. 572-3993 or fax (317) 572-4002. Trademarks: Wiley, the Wiley Publishing logo, Audel, and related trade dress are trade- marks or registered trademarks of