Electrical Engineering
Concepts and Applications


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Electrical Engineering
Concepts and Applications
S. A. Reza Zekavat
Michigan Technological University

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Library of Congress Cataloging-in-Publication Data
Zekavat, Seyed A.
Electrical engineering: concepts and applications / Seyed A. (Reza) Zekavat.—1st ed.
p. cm.
ISBN-13: 978-0-13-253918-0
ISBN-10: 0-13-253918-7
1. Electrical engineering—Textbooks. I. Title.
TK165.Z45 2012
621.3—dc23
2011029582

10

9


8

7

6

5

4

3

2

1
ISBN 10: 0-13-253918-7
ISBN 13: 978-0-13-253918-0


Dedication
To my father, Seyed Hassan, and mother Azardokht


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CONTENTS
Preface xvii
Acknowledgements


xix

Chapter 1 Why Electrical Engineering?
1.1
1.2
1.3
1.4
1.5

1

Introduction 1
Electrical Engineering and a Successful Career 2
What Do You Need to Know about EE? 2
Real Career Success Stories 3
Typical Situations Encountered on the Job 4
1.5.1

On‐the‐Job Situation 1: Active Structural Control 4

1.5.2

On‐the‐Job Situation 2: Chemical Process Control 6

1.5.3

On‐the‐Job Situation 3: Performance of an Off‐Road Vehicle Prototype 8

Further Reading 12


Chapter 2 Fundamentals of Electric Circuits
2.1
2.2
2.3
2.4
2.5
2.6
2.7

2.8

Introduction 13
Charge and Current 15
Voltage 17
Respective Direction of Voltage and Current 18
Kirchhoff’s Current Law 18
Kirchhoff’s Voltage Law 22
Ohm’s Law and Resistors 27
2.7.1

Resistivity of a Resistor 29

2.7.2

Nonlinear Resistors 32

2.7.3

Time‐Varying Resistors 32


Power and Energy 32
2.8.1

2.9
2.10

13

Resistor‐Consumed Power 36

Independent and Dependent Sources 38
Analysis of Circuits Using PSpice 42
Bias Point Analysis 45
Time Domain (Transient) Analysis 46
Copy the Simulation Plot to the Clipboard to Submit Electronically 47

2.11

What Did You Learn? 53
Problems 54

Chapter 3 Resistive Circuits
3.1
3.2
3.3

61

Introduction 61

Resistors in Parallel and Series and Equivalent Resistance 62
Voltage and Current Division/Divider Rules 71
3.3.1

Voltage Division 71

3.3.2

Current Division 74

vii


viii

Contents

3.4

3.5
3.6

Nodal and Mesh Analysis 81
3.4.1

Nodal Analysis 81

3.4.2

Mesh Analysis 88


Special Conditions: Super Node 92
Thévenin/Norton Equivalent Circuits 99
3.6.1

3.7
3.8
3.9
3.10

Source Transformation 108

Superposition Principle 112
Maximum Power Transfer 118
Analysis of Circuits Using PSpice 122
What Did You Learn? 125
Problems 126

Chapter 4 Capacitance and Inductance
4.1
4.2

4.3

4.4

4.5

4.6


4.7
4.8

135

Introduction 135
Capacitors 136
4.2.1

The Relationship Between Charge, Voltage, and Current 138

4.2.2

Power 140

4.2.3

Energy 140

Capacitors in Series and Parallel 141
4.3.1

Series Capacitors 141

4.3.2

Parallel Capacitance 142

Inductors 147
4.4.1


The Relationship Between Voltage and Current 147

4.4.2

Power and Stored Energy 148

Inductors in Series and Parallel 149
4.5.1

Inductors in Series 150

4.5.2

Inductors in Parallel 150

Applications of Capacitors and Inductors 152
4.6.1

Fuel Sensors 152

4.6.2

Vibration Sensors 153

Analysis of Capacitive and Inductive Circuits Using PSpice 156
What Did You Learn? 158
Problems 159

Chapter 5 Transient Analysis

5.1
5.2

5.3
5.4
5.5

164

Introduction 164
First‐Order Circuits 165
5.2.1

RC Circuits 165

5.2.2

RL Circuits 179

DC Steady State 186
DC Steady State for Capacitive–Inductive Circuits 188
Second‐Order Circuits 189


Contents

5.6
5.7
5.8


5.5.1

Series RLC Circuits with a DC Voltage Source 189

5.5.2

Parallel RLC Circuits with a DC Voltage Source 196

Transient Analysis with Sinusoid Forcing Functions 198
Using PSpice to Investigate the Transient Behavior of RL and RC Circuits 201
What Did You Learn? 207
Problems 208

Chapter 6 Steady‐State AC Analysis
6.1

6.2

Introduction: Sinusoidal Voltages and Currents 215
6.1.1

Root‐Mean‐Square (rms) Values (Effective Values) 220

6.1.2

Instantaneous and Average Power 221

Phasors 222
6.2.1


6.3

6.4
6.5

6.6

6.7
6.8

215

Phasors in Additive or (Subtractive) Sinusoids 224

Complex Impedances 225
6.3.1

The Impedance of a Resistor 225

6.3.2

The Impedance of an Inductor 225

6.3.3

The Impedance of a Capacitor 226

6.3.4

Series Connection of Impedances 228


6.3.5

Parallel Connection of Impedances 229

Steady‐State Circuit Analysis Using Phasors 231
Thévenin and Norton Equivalent Circuits with Phasors 239
6.5.1

Thévenin Equivalent Circuits with Phasors 239

6.5.2

Norton Equivalent Circuits with Phasors 240

AC Steady‐State Power 243
6.6.1

Average Power 245

6.6.2

Power Factor 246

6.6.3

Reactive Power 246

6.6.4


Complex Power 247

6.6.5

Apparent Power 249

6.6.6

Maximum Average Power Transfer 252

6.6.7

Power Factor Correction 254

Steady‐State Circuit Analysis Using PSpice 259
What Did You Learn? 265
Problems 267

Chapter 7 Frequency Analysis
7.1
7.2

Introduction 274
First‐Order Filters 275
7.2.1

7.3

274


Transfer Functions 275

Low‐Pass Filters 276
7.3.1

Magnitude and Phase Plots 280

7.3.2

Decibels 280

7.3.3

Bode Plot 282

ix


x

Contents

7.4

High‐Pass Filters 285
7.4.1

7.5

7.6

7.7
7.8

Cascaded Networks 287

Second‐Order Filters 289
7.5.1

Band‐Pass Filters 289

7.5.2

Band‐Stop Filters 291

MATLAB Applications 293
Frequency Response Analysis Using PSpice 300
What Did You Learn? 309
Problems 310

Chapter 8 Electronic Circuits 316
8.1
8.2
8.3

8.4

8.5
8.6
8.7


Introduction 316
P‐Type and N‐Type Semiconductors 317
Diodes 319
8.3.1

Diode Applications 323

8.3.2

Different Types of Diodes 329

8.3.3

AC‐to‐DC Converter 335

Transistors 338
8.4.1

Bipolar Junction Transistor 338

8.4.2

Transistor as an Amplifier 339

8.4.3

Transistors as Switches 356

8.4.4


Field‐Effect Transistors 357

8.4.5

Design of NOT Gates Using NMOS Only for High‐Density Integration 367

8.4.6

Design of a Logic Gate Using CMOS 369

Operational Amplifiers 371
Using PSpice to Study Diodes and Transistors 377
What Did You Learn? 385
Further Reading 385
Problems 386

Chapter 9 Power Systems and Transmission Lines
9.1
9.2

395

Introduction 395
Three‐Phase Systems 396
9.2.1

Introduction 396

9.2.2


Phase Sequence 398

9.2.3

Y‐Connected Generators 398

9.2.4

Y‐Connected Loads 398

9.2.5

∆‐Connected Loads 401

9.2.6

∆‐Star and Star‐∆ Transformations 404

9.2.7

Power in Three‐Phase Systems 406

9.2.8

Comparison of Star and ∆ Load Connections 411

9.2.9

Advantages of Three‐Phase Systems 411



Contents

9.3

9.4
9.5

Transmission Lines 412
9.3.1

Introduction 412

9.3.2

Resistance (R) 414

9.3.3

Different Types of Conductors 415

9.3.4

Inductance (L) 416

9.3.5

Capacitance 421

9.3.6


Transmission Line Equivalent Circuits 424

Using PSpice to Study Three‐Phase Systems 432
What Did You Learn? 435
Further Reading 435
Problems 436

Chapter 10 Fundamentals of Logic Circuits
10.1
10.2

440

Introduction 440
Number Systems 442
10.2.1 Binary Numbers 442
10.2.2 Hexadecimal Numbers 449
10.2.3 Octal Numbers 450

10.3

Boolean Algebra 451
10.3.1 Boolean Inversion 451
10.3.2 Boolean AND Operation 451
10.3.3 Boolean OR Operation 452
10.3.4 Boolean NAND Operation 452
10.3.5 Boolean NOR Operation 452
10.3.6 Boolean XOR Operation 452
10.3.7 Summary of Boolean Operations 452

10.3.8 Rules Used in Boolean Algebra 452
10.3.9 De Morgan’s Theorems 453
10.3.10 Commutativity Rule 454
10.3.11 Associativity Rule 454
10.3.12 Distributivity Rule 454

10.4

Basic Logic Gates 459
10.4.1 The NOT Gate 459
10.4.2 The AND Gate 459
10.4.3 The OR Gate 460
10.4.4 The NAND Gate 460
10.4.5 The NOR Gate 460
10.4.6 The XOR Gate 463
10.4.7 The XNOR Gate 463

10.5

Sequential Logic Circuits 466
10.5.1 Flip‐Flops 466
10.5.2 Counter 470

xi


xii

Contents


10.6
10.7

Using PSpice to Analyze Digital Logic Circuits 474
What Did You Learn? 481
Reference 482
Problems 483

Chapter 11 Computer‐Based Instrumentation Systems
11.1
11.2

11.3

11.4

11.5

Introduction 488
Sensors 489
11.2.1

Pressure Sensors 490

11.2.2

Temperature Sensors 491

11.2.3


Accelerometers 497

11.2.4

Strain‐Gauges/Load Cells 498

11.2.5

Acoustic Sensors 500

11.2.6

Linear Variable Differential Transformers (LVDT) 503

Signal Conditioning 505
11.3.1

Amplifiers 505

11.3.2

Active Filters 505

Data Acquisition 511
11.4.1

Analog Multiplexer 511

11.4.2


Analog‐to‐Digital Conversion 511

Grounding Issues 514
11.5.1

11.6
11.7

488

Ground Loops 514

Using PSpice to Demonstrate a Computer‐Based Instrument 516
What Did You Learn? 519
Further Reading 519
Problems 519

Chapter 12 Principles of Electromechanics
12.1
12.2

524

Introduction 524
Magnetic Fields 525
12.2.1 Magnetic Flux and Flux Intensity 526
12.2.2 Magnetic Field Intensity 527
12.2.3 The Right‐Hand Rule 527
12.2.4 Forces on Charges by Magnetic Fields 528
12.2.5 Forces on Current‐Carrying Wires 528

12.2.6 Flux Linkages 530
12.2.7 Faraday’s Law and Lenz’s Law 530

12.3

Magnetic Circuits 530
12.3.1 Magnetomotive Force 531
12.3.2 Reluctance 532

12.4

Mutual Inductance and Transformers 538
12.4.1 Mutual Inductance 539
12.4.2 Transformers 542


Contents

12.5
12.6
12.7

Different Types of Transformers 547
Using PSpice to Simulate Mutual Inductance and Transformers 547
What Did You Learn? 552
Problems 552

Chapter 13 Electric Machines
13.1


13.2

557

Introduction 557
13.1.1

Features of Electric Machines 558

13.1.2

Classification of Motors 558

DC Motors 559
13.2.1 Principle of Operation 559
13.2.2 Assembly of a Typical DC Motor 559
13.2.3 Operation of a DC Motor 560
13.2.4 Losses in DC Machines 561

13.3

Different Types of DC Motors 563
13.3.1 Analysis of a DC Motor 563
13.3.2 Shunt‐Connected DC Motor 566
13.3.3 Separately Excited DC Motors 567
13.3.4 Permanent Magnet (PM) DC Motor 568
13.3.5 Series‐Connected DC Motor 571
13.3.6 Summary of DC Motors 573

13.4


Speed Control Methods 573
13.4.1 Speed Control by Varying the Field Current 573
13.4.2 Speed Control by Varying the Armature Current 575

13.5

DC Generators 576
13.5.1 The Architecture and Principle of Operation of a DC Generator 576
13.5.2 emf Equation 577

13.6

Different Types of DC Generators 578
13.6.1 Load Regulation Characteristics of DC Generators 578
13.6.2 Separately Excited DC Generator 579
13.6.3 Shunt‐Connected DC Generator 580

13.7

13.8

AC Motors 580
13.7.1

Three‐Phase Synchronous Motors 581

13.7.2

Three‐Phase Induction Motor 584


13.7.3

Losses in AC Machines 591

13.7.4

Power Flow Diagram for an AC Motor 591

AC Generators 592
13.8.1 Construction and Working 593
13.8.2 Winding Terminologies for the Alternator 593
13.8.3 The emf Equation of an Alternator 595

13.9

Special Types of Motors 597
13.9.1 Single‐Phase Induction Motors 597
13.9.2 Stepper Motors 597

xiii


xiv

Contents

13.9.3 Brushless DC Motors 599
13.9.4 Universal Motors 600


13.10 How is the Most Suitable Motor Selected? 602
13.11 Setup of a Simple DC Motor Circuit Using PSpice 603
13.12 What Did You Learn? 610
Further Reading 611
Problems 611

Chapter 14 Electrical Measurement Instruments
14.1
14.2
14.3

615

Introduction 615
Measurement Errors 616
Basic Measurement Instruments 619
14.3.1 An Ammeter Built Using a Galvanometer 619
14.3.2 A Voltmeter Built Using a Galvanometer 620
14.3.3 An Ohmmeter Built Using a Galvanometer 621
14.3.4 Multi‐Meters 621

14.4

Time Domain and Frequency Domain 625
14.4.1 The Time Domain 625
14.4.2 The Frequency Domain 626
14.4.3 Time Domain Versus Frequency Domain 627

14.5
14.6


The Oscilloscope 628
The Spectrum Analyzer 633
14.6.1 Adjusting the Spectrum Analyzer’s Display Window 633

14.7
14.8

The Function Generator 639
What Did You Learn? 640
Problems 641

Chapter 15 Electrical Safety 646
15.1
15.2

Introduction 646
Electric Shock 646
15.2.1 Shock Effects 647
15.2.2 Shock Prevention 649

15.3

Electromagnetic Hazards 649
15.3.1 High‐Frequency Hazards 649
15.3.2 Low‐Frequency Hazards 651
15.3.3 Avoiding Radio Frequency Hazards 655

15.4


Arcs and Explosions 655
15.4.1 Arcs 655
15.4.2 Blasts 657
15.4.3 Explosion Prevention 657

15.5

The National Electric Code 658
15.5.1 Shock Prevention 658
15.5.2 Fire Prevention 663


Contents

15.6

What Did You Learn? 665
References 666
Problems 666

Appendix A: Solving Linear Equations
Appendix B: Laplace Transform

673

Appendix C: Complex Numbers

677

Selected Solutions

Index

687

683

671

xv


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PREFACE
A multi-disciplinary effort was initiated at Michigan Technological University, with a support
from the U.S. National Science Foundation’s Engineering Education division. The goal was to
create a curriculum that (1) encourages students to pursue the life-long learning necessary to
keep pace with the rapidly-evolving engineering industry and emerging interdisciplinary technologies, (2) maintains sufficient connection between the students’ chosen engineering fields
and class content; and (3) motivates and excite the students about the importance of EE concepts
to their discipline and career.
Seven faculty members across different departments contributed to this process.
Participating departments included: electrical engineering, chemical engineering, civil and environmental engineering, mechanical engineering, biomedical engineering, and the education
division of the cognitive and learning science department. The group’s curriculum reform efforts were informed by a nationwide survey of engineering schools. The survey outcomes were
analyzed to fine tune different curriculum options for this course for different engineering disciplines. Then, those options were integrated to create the final draft of the curriculum. The final
draft of the curriculum was used as a layout to create a new textbook for this course.
Although no single text can perfectly meet the needs of every institution, diverse topics
have been included to address the mixed survey response and allow this book to address the
needs of lecturers in different institutions worldwide. The resulting textbook creates a prototype curriculum available to electrical engineering departments that are charged with providing
an introduction to electrical engineering for non-EE majors. The goals of this new curriculum

are to be attractive, motivational, and relevant to students by creating many application-based
problems; and provide the optimal level of both range and depth of coverage of EE topics in a
curriculum package.
The book features:
a. Application-based examples: A large number of application-based examples were
selected from different engineering fields and are included in each chapter. They aim
to bridge EE and diverse non-EE areas. These examples help to address the question:
“why I should take this course?” Non-EE students will better understand: (1) why they
should learn how to solve circuits; and; (2) what are the applications of solving circuits in
mechanical, chemical, and civil engineering areas.
b. PSpice lectures, examples, and problems: The text offers a distributed approach for
learning PSpice. A PSpice component is integrated in many chapters. Chapter 2 provides
an initial tutorial, and new skills are added in Chapters 3–11. This part includes lectures
that teach students how to use PSpice and can be considered as an embedded PC-based lab
for the course. In addition, many PSpice-specific examples have been developed, which
help students better understand the process of building a circuit and getting the desired
results. There are also many end-of-chapter PSpice problems.
c. Innovative chapters: Based on our nationwide survey, the topics in these chapters have
been highlighted by many professionals as important topics for this course. It should be
noted that each instructor has the liberty to include or exclude some of these topics from
his/her curriculum. Some topics include:
• Chapter 1—Case Study: This chapter presents the applications of electrical engineering
components in mechanical engineering, chemical engineering, and civil engineering through real life scenarios. A bridge across these case studies and the topics that
will be covered later in the book is maintained. The goal is to better motivate students
by placing the concepts of electrical engineering in the context of their chosen fields
of study. Each section of this chapter was been prepared by a different member of the
faculty at Michigan Tech who contributed to the NSF project.

xvii



xviii Preface

• Chapter 7—Frequency Response with MATLAB and PSpice: This chapter discusses
the frequency response of circuits and introduces different types of filters and uses
MATLAB and PSpice examples and end-of chapter problems. This chapter creates an
opportunity for students to learn some features of MATLAB software. In other words,
this chapter promotes an integrated study using both PSpice and MATLAB.
• Power Coverage: Chapters 9, 12, 13—Based on our nationwide survey, and motivated
by concerns about global warming and the need for clean energy, industry respondents
requested a more thorough treatment of power. Thus, power coverage is supported by
three chapters. Chapter 9 introduces the concept of three-phase systems, transmission
lines, their equivalent circuits, and power transfer. Chapter 12 studies another important topic of energy transfer—transformers. Finally Chapter 13 studies the topic of
motors and generators. This chapter offers the concept of motors and generators in a
clear and concise approach. The chapter introduces applications of motors and generators and introduces many applications of both.
• Chapter 15—Electrical Safety: This unique chapter discusses interesting electric
safety topics useful in the daily life of consumers or engineers working in the field.
d. Examples and sorted end-of-chapter problems: The book comes with more than 1100
examples and end-of-chapter problems (solutions included). End-of-chapter problems are
sorted to help instructors select basic, average, and difficult problems.
e. A complete solution manual: A complete solutions manual for all problems will be available via download for all adopting professors.


ACKNOWLEDGMENTS
Professor William Bulleit (Civil and Environmental Engineering Department, Michigan Tech),
Professor Tony Rogers (Chemical Engineering Department, Michigan Tech) and Professor Harold
Evensen (Mechanical Engineering, Engineering Mechanics Department, Michigan Tech) are the
authors of chapter one. The research on this National Science Foundation project was conducted
with the support of many faculty members. Here, in addition to Professor Bulleit, Professor
Rogers and Professor Evensen, I should acknowledge the efforts of Professor Kedmon Hungwe

(Education Department, Michigan Tech), Mr. Glen Archer (Electrical and Computer Engineering
Department, Michigan Tech), Professor Corina Sandu (Mechanical Engineering Department,
Virginia Tech), Professor David Nelson (Mechanical Engineering Department, University of
South Alabama), Professor Sheryl Sorby (Mechanical Engineering, Engineering Mechanics
Department, Michigan Tech), and Professor Valorie Troesch (Institute for Interdisciplinary
Studies, Michigan Tech). The preparation of the book was not possible without the support of
many graduate students that include Luke Mounsey, Xiukui Li, Taha Abdelhakim, Shu G. Ting,
Wenjie Xu, Zhonghai Wang, Babak Bastaami, Manaas Majumdar, Abdelhaseeb Ahmed, Daw
Don Cheam, Jafar Pourrostam and Greg Price. I would like to thank all of them. Moreover, I
should thank the support of the book’s grand reviewer Mr. Peter A. Larsen (Sponsored Programs,
Michigan Tech) which improved the quality of its presentation. In addition, I should acknowledge many colleagues whose names are listed below, who reviewed the book and provided me
with invaluable comments and feedback.
Paul Crilly—University of Tennessee
Timothy Peck—University of Illinois
George Shoane—Rutgers University
Ziqian Liu—SUNY Maritime College
Ralph Tanner—Western Michigan University
Douglas P. Looze—University of Massachusetts, Amherst
Jaime Ramos-Salas—University of Texas, Pan American
Dale Dolan—California Polytechnic State University, San Luis Obispo
Munther Hassouneh—University of Maryland
Jacob Klapper—New Jersey Institute of Technology
Thomas M. Sullivan—Carnegie Mellon University
Vijayakumar Bhagavatula—Carnegie Mellon University
S. Hossein Mousavinezhad—Idaho State University
Alan J. Michaels—Harris Corporation
Sandra Soto-Caban—Muskingum University
Wei Pan—Idaho State University
Finally, I should acknowledge the support of late Professor Derek Lile, the former department head
of Electrical and Computer Engineering of Colorado State University, while I was creating the

ideas of this project while I was a Ph.D. candidate at Colorado State University, Ft. Collins, CO.
S. A. Reza Zekavat
Michigan Technological University

xix


Electrical Engineering
Concepts and Applications


CHAPTER

1

Why Electrical Engineering?

A
R1

R2
V0

R4
C

+

D


1.1 Introduction
1.2 Electrical Engineering
and a Successful Career
1.3 What Do You Need to
Know About EE?
1.4 Real Career Success
Stories
1.5 Typical Situations
Encountered on the Job

R3
(Strain gage)

1.1 INTRODUCTION
If you are reading these words, then you are probably an engineering student who is about to take a course in electrical engineering (EE), or possibly an engineer who wants to learn about EE. In either case, it is safe
to say that you are not majoring in EE nor are you already an electrical
engineer. So, why are you doing this to yourself?
As an engineering student, there are two likely possible reasons:
(1) You are being forced to because it is required for your major, and/or
(2) you believe that it will help you pass the Fundamentals of Engineering
(FE) examination that you will take before you graduate or shortly thereafter. If you are already an engineer, then you are likely reading this book
because you need to learn EE for the FE exam that you put off until after
graduation, or you need to learn EE to perform your job better. Studying
EE because it is required for you to graduate or because you want all the
help you can get to pass the FE exam are both laudable reasons. But, the
second possible reason mentioned earlier for our hypothetical practicing engineer needs to be considered further. Can learning EE help you
in your engineering career? The short answer is, yes. The long answer
follows.

1



2

Chapter 1 • Why Electrical Engineering

1.2 ELECTRICAL ENGINEERING AND A SUCCESSFUL CAREER
As a practicing engineer, you will work on projects that require a wide range of different engineers
and engineering disciplines. Communication among those engineers will be vital to the successful completion of the project. You will be in a better position to communicate with the engineers
working on electrical systems of all sorts if you have a basic background in EE. Certainly—
through this course alone—you will not be able to design complicated electrical systems, but you
will be able to get a feel of how the system works and be better able to discuss the implications of
areas where the non-EE system you are designing and the electrical system overlap. For example,
mechanical engineers often design packages for electronic systems where heat dissipation due to
electronic components can be a major problem. In this instance, the non-EE engineer should be
able to help the EE with component placement for optimum heat dissipation. In short, no engineer
works in isolation and the more you can communicate with other engineers the better.
The company that hires you out of engineering school understands how important communication is. Thus, they will most likely have training programs that help their engineers learn more about the
specific engineering that they will perform as well as other engineering disciplines with which they will
be associated. If you have taken EE as an engineering student, then you will have a good foundation for
learning EE topics specific to that company, which will make your on-the-job training easier and, consequently, less expensive for your employer. Saving money for your employer is always a good thing.
So, by having taken an EE course, you will be a more promising hire for many companies.
In addition, there will be instances in your engineering career where you will be working
directly with electrical or electronic components that you need to understand in some depth. For
example, many engineers work in manufacturing processing and will need to work with products
that have electrical/electronic content. Likewise, engineers often work with systems that used to be
mechanical, but are now electronic (e.g., electronic fuel injection, electronic gas pedals). In the course
of your work, you may also need to perform tests in which the test apparatus uses a Wheatstone
bridge. If that is the case, then you need to know how a Wheatstone bridge, which is an electric
circuit, works to use the equipment adequately. In addition, most mechanical measurements involve

converting the mechanical quantity to an electrical signal. Finally, if you need to purchase electrical
components and equipment you will need a fundamental background in EE to talk to the vendor in an
intelligent manner and get the type of equipment that your company needs. Thus, by knowing some
EE, you will be better able to obtain and use electrical components and electrical equipment.
Another reason for learning the principles and practices of EE is that you may be able to
make connections between your engineering discipline and EE that lead to creative problem
solutions or even inventions. For instance, maybe your job will require you to monitor a system
on a regular basis that requires you to perform a significant number of tedious by-hand techniques. Your familiarity with the monitoring process, combined with your background in EE,
might allow you to teach yourself enough in-depth EE to design and build a prototype monitoring system that is faster and less hands-on. This type of invention could lead to a patent or could
lead to a significant savings in monitoring costs for your company. In this scenario, you would
have been able to do the work yourself and would thus gain ownership of your work and ideas,
that is, the design and fabrication of a prototype monitoring system. Learning EE (as well as
other engineering fundamentals outside your specific discipline) may allow you to make connections that could lead to creative solutions to certain types of engineering problems.
In conclusion, studying EE will not only help you pass the FE exam, but it will make you
more marketable, give you capabilities that will enhance your engineering career, and increase your
self-confidence, all of which may allow you to solve problems in ways you cannot now imagine.

1.3 WHAT DO YOU NEED TO KNOW ABOUT EE?
Electric circuits are an integral part of nearly every product on the market. In any engineering
career, you will need a working knowledge of circuits and the various elements that make up
a circuit, including resistors, capacitors, transistors, power supplies, switches, and others. You


Section 1.4 • Real Career Success Stories

need to know circuit analysis techniques and by learning these gain an understanding of how
voltage, current, and power interact. You will likely be required to purchase equipment during
your career, so you will need to learn how to determine technical specifications for that equipment. Working with electrical equipment exposes you to certain hazards with which you must
be aware. Thus, you will need to learn to respect electrical systems and work with them safely.
Although engineers in all disciplines are expected to understand and use electrical systems, power sources, and circuits in many job assignments, expert knowledge is not required.

For example, many non-EEs are plant managers and are called upon to manage heating and air
conditioning (HVAC) systems. While the engineer will not be asked to design the system or its
components, a basic EE knowledge is useful for day-to-day management. The practicing engineer must be able to design and analyze simple circuits and be able to convey technical requirements to vendors, electricians, and electrical and computer engineers.
A typical on-the-job application is data acquisition from temperature, pressure, and flow
sensors that monitor process or experimental equipment. Process control and monitoring situations in plants and refineries require working knowledge of data acquisition and logging, signal
processing, analog-to-digital (A/D) conversion, and interfacing valves and other control devices
with controllers. In-line, real-time chemical analysis is sometimes necessary, as well as monitoring process temperatures, pressures, and flow rates with in-line sensors.
Familiarity with power generation and general knowledge of generators, electric motors,
and power grids is also beneficial to engineers. A major job objective is frequently to reduce
utility expenses, primarily electricity costs. For example, EE knowledge is necessary to design
and operate cogeneration systems for simultaneous production of heat and electricity. In such
situations, high-pressure steam can be throttled through a turbine-generator system for power
production, and the lower-pressure exhaust steam is available for plant use. Alternatively, natural
gas can be combusted in a gas turbine to generate electricity, and the hot gas exhaust can make
steam in a boiler. One issue is how to operate the system to match electricity use patterns in the
plant.
Process engineers also need to recapture energy (as electricity) from process streams possessing high thermodynamic availability, that is, streams at high pressure and/or temperature.
Often, this can be done by putting the process stream through an isentropic expander (turbine)
and using the resulting shaft work to operate an electric generator.
Electrochemistry involves knowledge and use of potentiostats, battery testing equipment,
cyclic voltammetry measurements, electrode selection, and electrochemical cells. Electroplating
operations are also of interest to chemical engineers. A background in EE will help you understand these and other related processes.

1.4 REAL CAREER SUCCESS STORIES
The bottom line for engineers is frequently the economic consequence of operating a process.
The profit motive is paramount, with safety and environmental considerations providing constraints in operation. Electrical engineering principles often directly affect a process’s profitability and operability. Learning and applying the concepts in this textbook may help you get noticed
(favorably) in a future job by saving money for your company.
Consider the case of a chemical engineering graduate who began work a few years ago in
a major refinery that had recently implemented a cogeneration system that produced steam and
electric power simultaneously. Generation of high-pressure steam in a natural gas fired boiler,

followed by expansion of the steam through a turbine, produced shaft work that was used to
operate a generator. For internal plant use, this generated electricity was valued at the retail
electricity price. (External sale of excess electricity is regulated by the Public Utility Resource
Power Act (PUPA), and the price is the cost the utility company incurs to make incremental electricity, i.e., the utility company’s “avoided cost.”) The new employee did an economic analysis,
looking at the trade-off between the equipment capital investments and operating costs versus

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