Table Of ContentElectricity for
the Entertainment
Electrician & Technician
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Electricity for
the Entertainment
Electrician & Technician
Richard Cadena
AmsterdAm • Boston • HeidelBerg • london • new York
oxford • PAris • sAn diego • sAn frAncisco
singAPore • sYdneY • tokYo
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Library of Congress Cataloging-in-Publication Data
Cadena, Richard.
Electricity for the entertainment electrician & technician / Richard Cadena.
p. cm.
Includes bibliographical references and index.
ISBN 978-0-240-80995-3 (pbk. : alk. paper) 1. Electricity–Safety
measures. 2. Electric circuits. 3. Electric wiring, Indoor. 4. Stage
lighting. 5. Leisure industry–Electric equipment. I. Title.
TK152.C2185 2009
iv 621.319’24–dc22
2008046915
British Library Cataloguing-in-Publication Data
A catalogue record for this book is available from the British Library.
ISBN: 978-0-240-80995-3
For information on all Focal Press publications
visit our website at www.books.elsevier.com
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This book is dedicated to the most dedicated people I know — Yolanda and
Noe Cadena, a.k.a., Mom and Dad.
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Contents
Preface .................................................................................................................xiii
acknowledgments ....................................................................................................xv
IntroductIon ...............................................................................................................xvii
what Is an entertainment electrician? ........................................xvii
technology moves on ....................................................................xviii
keeping up with technology ..........................................................xix
overview ................................................................................................xx
electricity kills, But It doesn’t Have to .....................................xxiii
Chapter 1 The Theory of Electricity ...............................................................1
what Is electricity? ................................................................................1 vii
electrons in motion ...............................................................................2
the atom .................................................................................................2
subatomic Particles ..............................................................................3
electrostatic charges ...........................................................................3
electronic drift .......................................................................................5
conductive Properties of materials .................................................6
current convention ...............................................................................8
summary ..................................................................................................9
understanding electricity ....................................................................9
Chapter 2 Electrical Concepts .........................................................................11
Pulling Back the Veil of mystery ......................................................11
Voltage ....................................................................................................11
current....................................................................................................12
resistance .............................................................................................13
Power .....................................................................................................13
energy ....................................................................................................14
Contents
sI units of measure: amperes, Volts, ohms, siemens,
Joules, watts ...................................................................................15
the ampere ......................................................................................15
the Volt .............................................................................................16
the ohm ............................................................................................16
the siemens .....................................................................................16
the Joule ...........................................................................................18
the watt ............................................................................................18
conservation of energy ....................................................................20
understanding electrical concepts ...............................................20
Chapter 3 DC Electricity ....................................................................................21
the dc circuit .....................................................................................23
ohm’s law ...........................................................................................24
dc Power .............................................................................................26
understanding dc electricity ..........................................................29
Chapter 4 AC Electricity ....................................................................................31
magnetism .............................................................................................31
electromagnetism ..............................................................................33
viii
magnetic Induction ............................................................................35
faraday’s law of Induction .............................................................35
fleming’s right-Hand rule..............................................................37
the ac generator ..............................................................................38
exercise Your knowledge of sinewaves .....................................42
frequency ............................................................................................45
the sinewave ......................................................................................46
rms Value ...........................................................................................47
true rms meters ...............................................................................49
understanding ac electricity ..........................................................55
Chapter 5 Circuit Elements .............................................................................59
series resistance ...............................................................................60
Parallel resistance .............................................................................61
series/Parallel resistance ...............................................................63
real-world resistance .....................................................................64
Impedance ............................................................................................65
Contents
reactance .............................................................................................65
Inductors ...............................................................................................65
capacitors .............................................................................................68
Phase angles ........................................................................................71
complex Impedance...........................................................................72
transformers .......................................................................................75
understanding circuit elements .....................................................78
Chapter 6 AC Power ...........................................................................................83
ac Power formula .............................................................................85
Power factor ......................................................................................85
Power factor correction ..................................................................86
complex Power ...................................................................................87
three-Phase Power ...........................................................................89
three-Phase Power calculations ....................................................91
understanding ac Power ................................................................93
Chapter 7 Electrical Safety ............................................................................95
electric shock ......................................................................................95
effects of electrical current ............................................................96
ix
arc flash and arc Blast ....................................................................97
lockout/tagout ................................................................................100
drugs and alcohol ............................................................................102
understanding electrical safety ..................................................102
Chapter 8 Grounding/Earthing ..................................................................105
the complete circuit .......................................................................105
earthing/grounding .........................................................................106
Zero-Volt reference .......................................................................106
Voltage stability ...............................................................................108
safety grounding .............................................................................108
grounded Versus grounding Versus Bonding ...........................110
uni-grounding Versus multi-grounding ......................................110
ground loops ......................................................................................111
Balanced Power systems ...............................................................112
technical earth/technical ground ...............................................114
understanding grounding concepts ............................................114
