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Grounding and Bonding for the Radio Amateur ARRL.Pdf Copyright © by The American Radio Relay League, )nc. Copyright secured under the Pan-American Convention All rights reserved. No part of this work may be reproduced in any form except by written permission of the publisher. All rights of translation are reserved. Printed in USA Quedan reservados todos los derechos )SBN: ---- First Edition eBooks created by www.ebookconversion.com We strive to produce books without errors. Sometimes mistakes do occur, however. When we become aware of problems in our books other than obvious typographical errors, we post corrections on the ARRL website. )f you think you have found an error, please check www.arrl.org/notes for corrections. )f you dont find a correction there, please let us know by sending e-mail to [email protected]. CONTENTS Preface About ARRL Chapter — )ntroduction . What Are Grounding and Bonding? . Materials — An )ntroduction . Techniques and Tools — An )ntroduction . Things to Find Out Chapter — Grounding and Bonding Basics . Using the Right Term . )mportant Standards and Guidelines Chapter — AC Power System Grounding and Bonding . Safety First — Always . Shock (azards . Power System Grounding and Bonding . AC Safety Grounding Specifics . AC Power in Your Station Chapter — Lightning Protection . What is Lightning? . Controlling Current Paths . Protecting Against Voltage Transients . Bonding to Equalize Voltages Chapter — RF Management . Your Station, the RF System . RF Fundamentals . Bonding to Equalize Audio and RF Voltage . Blocking RF Current with Chokes . Miscellaneous Topics Chapter — Good Practice Guidelines . Ground Electrodes . AC Power . Lightning Protection Planning . Managing RF in the Station . Practical Stations Appendix Resources for )nformation and Materials Material Sizes and Values Wiring for V and V ac Plugs and Outlets Common-Mode Chokes and Ferrite Characteristics Glossary PREFACE This book is largely a distillation of expertise contributed by others, both professional and amateur. )t is based on their thousands of hours of work to determine safe and effective ways of protecting ourselves and building our stations. The author recognizes that the deep experts pave the way for us and encourages the reader to follow up with the references and resources listed in the book. There is much more to this subject than could ever be included in this relatively introductory book. Along with those who developed the know-how, the author is most appreciative of the reviewers and other sources who contributed to this book: Ron Block, NRB; Dale Svetanoff, WAENA; Jim Brown, KYC; Joel (allas, WZR; Alan Applegate, K1BG; DX Engineering; and the ARRL Lab staff. Any remaining errors are those of the author. A caution to the reader — the practices and recommendations in this book are not guaranteed to prevent damage to equipment or insure personal safety. )t is the responsibility of the station builder to comply with all applicable standards and regulations, use adequately rated and listed materials, and maintain the station and equipment properly. )f you are unsure of your ability to do the job correctly, hire a professional to perform or inspect your work. Where electricity is concerned, there is no substitute for careful work, attention to detail, and personal vigilance. Switch to safety! (. Ward Silver, N1AX St. Charles, Missouri February ABOUT ARRL The seed for Amateur Radio was planted in the s, when Guglielmo Marconi began his experiments in wireless telegraphy. Soon he was joined by dozens, then hundreds, of others who were enthusiastic about sending and receiving messages through the air — some with a commercial interest, but others solely out of a love for this new communications medium. The United States government began licensing Amateur Radio operators in . By , there were thousands of Amateur Radio operators — hams — in the United States. (iram Percy Maxim, a leading (artford, Connecticut inventor and industrialist, saw the need for an organization to unify this fledgling group of radio experimenters. )n May he founded the American Radio Relay League ARRL to meet that need. ARRL is the national association for Amateur Radio in the US. Today, with approximately , members, ARRL numbers within its ranks the vast majority of active radio amateurs in the nation and has a proud history of achievement as the standard-bearer in amateur affairs. ARRLs underpinnings as Amateur Radios witness, partner, and forum are defined by five pillars: Public Service, Advocacy, Education, Technology, and Membership. ARRL is also )nternational Secretariat for the )nternational Amateur Radio Union, which is made up of similar societies in countries around the world. ARRL’s Mission Statement: To advance the art, science, and enjoyment of Amateur Radio. ARRL’s Vision Statement: As the national association for Amateur Radio in the United States, ARRL: Supports the awareness and growth of Amateur Radio worldwide; Advocates for meaningful access to radio spectrum; Strives for every member to get involved, get active, and get on the air; Encourages radio experimentation and, through its members, advances radio technology and education; and Organizes and trains volunteers to serve their communities by providing public service and emergency communications. At ARRL headquarters in the (artford, Connecticut suburb of Newington, the staff helps serve the needs of members. ARRL publishes the monthly journal QST and an interactive digital version of QST, as well as newsletters and many publications covering all aspects of Amateur Radio. )ts headquarters station, WAW, transmits bulletins of interest to radio amateurs and Morse code practice sessions. ARRL also coordinates an extensive field organization, which includes volunteers who provide technical information and other support services for radio amateurs as well as communications for public service activities. )n addition, ARRL represents US radio amateurs to the Federal Communications Commission and other government agencies in the US and abroad. Membership in ARRL means much more than receiving QST each month. )n addition to the services already described, ARRL offers membership services on a personal level, such as the Technical )nformation Service, where members can get answers — by phone, e-mail, or the ARRL website — to all their technical and operating questions. A bona fide interest in Amateur Radio is the only essential qualification of membership; an Amateur Radio license is not a prerequisite, although full voting membership is granted only to licensed radio amateurs in the US. Full ARRL membership gives you a voice in how the affairs of the organization are governed. ARRL policy is set by a Board of Directors one from each of Divisions. Each year, one- third of the ARRL Board of Directors stands for election by the full members they represent. The day-to-day operation of ARRL (Q is managed by a Chief Executive Officer and his/her staff. Join ARRL Today! No matter what aspect of Amateur Radio attracts you, ARRL membership is relevant and important. There would be no Amateur Radio as we know it today were it not for ARRL. We would be happy to welcome you as a member! Join online at www.arrl.org/join. For more information about ARRL and answers to any questions you may have about Amateur Radio, write or call: ARRL — The national association for Amateur Radio® Main Street Newington CT - Tel: -- FAX: -- e-mail: [email protected] www.arrl.org Prospective new radio amateurs call toll-free: --NEW (AM -- You can also contact ARRL via e-mail at [email protected] or check out the ARRL website at www.arrl.org Chapter Why )s This Book Needed? Why )s This Book Needed? When writing this book, ) thought about my own experiences starting out with a simple station and wondering why grounding seemed to be so important. My radio had a two-wire ac power cord but my vacuum-tube voltmeter had a three-wire power cord. ) didnt really think a lot about it but ) noticed that connections to a ground rod were shown frequently in the ARRL (andbook and books on antennas. There was a ground terminal on the back of my transceiver. The lightning arrestor ) purchased had a screw for attaching a ground wire. The books and articles had lots of drawings and pictures showing quite a variety of ways to connect equipment to the ground rod. There was rarely much of an explanation about what the ground rod was actually for or what the consequences of not having one might be — safety was mentioned a lot. So ) shrugged my shoulders, took it on faith that running a wire of some sort from my radio and antenna to a ground rod was Something A (am Should Do, and just did it. ) didnt notice any benefits or drawbacks from making the connection and when the wire came loose from the transceiver on occasion, that didnt seem to matter either. From years of operating and building all kinds of different stations, the functions of a ground rod and the connections between the equipment enclosures became clearer to me. As a professional engineer, ) learned about shielding and bonding, why the various ground connections were necessary, and the differences between them. Over the years, ) built up a set of techniques that worked reliably — at home, at Field Day, in a mobile station, in basements and on upper floors, even setting up a temporary station during my trip to Brazil as a World Radiosport Team Championship competitor. )t took me years to understand how all the various things we call grounding really worked. From years of reading online forums and magazine articles, it became clear there was a lot of confusion about what grounding was intended to accomplish and how to do it. So in the January issue of QST ) published the first of a series of three (ands-On Radio (OR columns, starting with The Myth of the RF Ground. The series explained some of the differences in ground connections and why the ground connection had different functions.
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