7
Copyright Goodheart-Willcox Co., Inc.
L. S. Starrett Company
O/Z Gedney Electric
National Fire Protection Association
PW Industries, Inc.
RACO, Inc.
Reliance Electric
Ridge Tool Company
S&C Electric Company
Southwire Company
Square D Company
Star Products Division, U.S. Trolley Corp.
Underwriters Laboratories, Inc.
Vermont American Tool Company
Wavetek Corporation
Westinghouse
The Wiremold Company
Illustration assistance
Marylin Agee, Square D Company
Patsy Campbell, Wavetek Corporation
Gary R. Carr , Greenlee Textron, Inc.
Sandra L. Davis, Ideal Industries
Mike Harrington
Peter Hayward, Westinghouse
Diane M. Khar, Square D Company
W.H. Korb, PW Industries, Inc.
Gale Langford, The Langford Group
Claudia K. Lester, Calculated Industries, Inc.
Ron Mabry
Marilyn Muscenti, Reliance Electric
Michael D. Myer, Star Products Division
Peg O’Neil, AVO International
Randy Polito
Kenneth R. Reinehr, Appleton Electric Company
Sheryl L. Schaffer, Electrical Testing Laboratories
Holly Jo Schubert, Underwriters Laboratories, Inc.
Amy Scoggin, Square D Company
Franny Singleton, Square D Company
Vicki Snapp, Square D Company
Beverly A. Summers, Fluke Corporation
Amy E. Takas, Chloride Systems
Anne Tighe, Hipotronics
Candace Tyndall, Square D Company
Lynn Watkins, Bussmann Div., Cooper Industries
Steve Wilcox, Furnas Electric Company
Janice A. Zimmerman, Klein Tools, Inc.
Richard J. Zuccaro, General Electric Company
Manuscript typing
Dahlia Tracey
Leslie Tracey
Melissa Rodriquez
Text Features
Many features have been incorporated into the design
of this text. These features are designed to aid in your
understanding of commercial wiring and to improve your
familiarity with the National Electrical Code®.
WARNING
Warnings indicate situations that may be harmful or
dangerous. Read Warnings carefully—what you learn
may prevent an accident someday.
CAUTION
Cautions warn of situations that may result in
damage to equipment or materials.
NOTE
NEC NOTE 90.3
NEC Notes provide a direct reference to applicable
material in the National Electrical Code. The Code
section from which the note is taken is referenced in
the heading. For instance, this note is labeled as being
contained in Section 90.3. NEC Notes contain only a
portion of the material in the referenced section—they
do not serve as a substitute for the National Electrical
Code. Always refer to the Code section for the appro-
priate information.
Pedagogical Features
The following features have been included to improve
comprehension:
• Technical Terms—Each chapter opens with a
list of Technical Terms. Read the list before
studying the chapter, pay special attention when
a term is defined in the text, and then review the
list after completing the chapter to be sure you
understand all the terms.
• Learning Objectives—Included in each chapter,
the Learning Objectives define the knowledge
and skills that will be gained when the chapter is
completed.
Notes provide additional information related to a topic.