Delmar's Standard Textbook of Electricity

1122 Pages·2009·43.197 MB·English

by  S. Herman

Delmar’s Standard Textbook of
ELECTRICITY
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FOURTH EDITION
Delmar’s Standard Textbook of
ELECTRICITY
Stephen L. Herman
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ofElectricity,4e
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Printed in Canada
1 2 3 4 5 XX 10 09 08
Contents
Preface xix
SECTION I
Safety, Basic Electricity, and Ohm’s Law 2
SAFETY OVERVIEW
S–1 General Safety Rules 4
S–2 Effects of Electric Current on the Body 6
S–3 On the Job 7
S–4 Protective Clothing 12
S–5 Ladders and Scaffolds 16
S–6 Fires 19
S–7 Ground-Fault Circuit Interrupters 20
S–8 Grounding 22
UNIT 1
Atomic Structure 28
1–1 Early History of Electricity 29
1–2 Atoms 31
1–3 The Law of Charges 35
1–4 Structure of the Atom 36
1–5 Electron Orbits 38
1–6 Valence Electrons 40
1–7 Electron Flow 41
1–8 Insulators 46
1–9 Semiconductors 46
1–10 Molecules 47
1–11 Methods of Producing Electricity 48
1–12 Electrical Effects 50
v
vi Contents
2
UNIT
Electrical Quantities and Ohm’s Law 53
2–1 The Coulomb 54
2–2 The Ampere 55
2–3 The Electron Flow Theory 56
2–4 The Conventional Current Flow Theory 56
2–5 Speed of Current 58
2–6 Basic Electric Circuits 61
2–7 The Volt 63
2–8 The Ohm 64
2–9 The Watt 66
2–10 Other Measures of Power 68
2–11 Ohm’s Law 70
2–12 Metric Prefixes 75
3
UNIT
Static Electricity 81
3–1 Static Electricity 82
3–2 Charging an Object 84
3–3 The Electroscope 84
3–4 Static Electricity in Nature 87
3–5 Nuisance Static Charges 90
3–6 Useful Static Charges 91
4
UNIT
Magnetism 96
4–1 The Earth Is a Magnet 97
4–2 Permanent Magnets 99
4–3 The Electron Theory of Magnetism 99
4–4 Magnetic Materials 101
4–5 Magnetic Lines of Force 102
4–6 Electromagnetics 104
4–7 Magnetic Measurement 107
4–8 Magnetic Polarity 109
4–9 Demagnetizing 109
4–10 Magnetic Devices 111
Contents vii
5
UNIT
Resistors 114
5–1 Uses of Resistors 115
5–2 Fixed Resistors 117
5–3 Color Code 120
5–4 Standard Resistance Values of Fixed Resistors 126
5–5 Power Ratings 128
5–6 Variable Resistors 129
5–7 Schematic Symbols 133
SECTION II
Basic Electric Circuits 136
6
UNIT
Series Circuits 137
6–1 Series Circuits 138
6–2 Voltage Drops in a Series Circuit 139
6–3 Resistance in a Series Circuit 141
6–4 Calculating Series Circuit Values 141
6–5 Solving Circuits 143
6–6 Voltage Dividers 156
6–7 The General Voltage Divider Formula 158
6–8 Voltage Polarity 159
6–9 Using Ground as a Reference 160
7
UNIT
Parallel Circuits 166
7–1 Parallel Circuit Values 167
7–2 Parallel Resistance Formulas 170
8
UNIT
Combination Circuits 192
8–1 Combination Circuits 193
8–2 Solving Combination Circuits 194
8–3 Simplifying the Circuit 195
viii Contents
9
UNIT
Kirchhoff’s Laws, Thevenin’s,Norton’s,
and Superposition Theorems 220
9–1 Kirchhoff’s Laws 221
9–2 Thevenin’s Theorem 228
9–3 Norton’s Theorem 232
9–4 The Superposition Theorem 236
SECTION III
Meters and Wire Sizes 250
10
UNIT
Measuring Instruments 251
10–1 Analog Meters 252
10–2 The Voltmeter 254
10–3 Multirange Voltmeters 256
10–4 Reading a Meter 258
10–5 The Ammeter 262
10–6 Ammeter Shunts 263
10–7 Multirange Ammeters 266
10–8 The Ayrton Shunt 266
10–9 AC Ammeters 271
10–10 Clamp-On Ammeters 275
10–11 DC-AC Clamp-On Ammeters 278
10–12 The Ohmmeter 281
10–13 Shunt-Type Ohmmeters 283
10–14 Digital Meters 284
10–15 The Low-Impedance Voltage Tester 288
10–16 The Oscilloscope 290
10–17 The Wattmeter 301
10–18 Recording Meters 303
10–19 Bridge Circuits 305
11
UNIT
Using Wire Tables and Determining
Conductor Sizes 311
11–1 Using the NEC®Charts 312
11–2 Factors That Determine Ampacity 316
Contents ix
11–3 Correction Factors 317
11–4 Computing Conductor Sizes and Resistance 323
11–5 Computing Voltage Drop 334
11–6 Parallel Conductors 335
11–7 Testing Wire Installations 338
SECTION IV
Small Sources of Electricity 346
12
UNIT
Conduction in Liquids and Gases 347
12–1 The Ionization Process:Magnesium and Chlorine 348
12–2 Other Types of Ions 350
12–3 Electroplating 352
12–4 Electrolysis 353
12–5 Conduction in Gases 353
12–6 Ionization in Nature 358
13
UNIT
Batteries and Other Sources of Electricity 361
13–1 History of the Battery 362
13–2 Cells 364
13–3 Cell Voltage 365
13–4 Primary Cells 366
13–5 Secondary Cells:Lead-Acid Batteries 375
13–6 Other Secondary Cells 381
13–7 Series and Parallel Battery Connections 384
13–8 Other Small Sources of Electricity 386
14
UNIT
Magnetic Induction 396
14–1 Electromagnetic Induction 397
14–2 Fleming’s Left-Hand Generator Rule 400
14–3 Moving Magnetic Fields 401
14–4 Determining the Amount of Induced Voltage 401
14–5 Lenz’s Law 402
14–6 Rise Time of Current in an Inductor 405