Basic AC Circuits -  Clay Rawlins

Basic AC Circuits (eBook)

(Autor)

eBook Download: PDF | EPUB
2000 | 2. Auflage
541 Seiten
Elsevier Science (Verlag)
978-0-08-049398-5 (ISBN)
62,95 € inkl. MwSt
Systemvoraussetzungen
62,50 € inkl. MwSt
Systemvoraussetzungen
  • Download sofort lieferbar
  • Zahlungsarten anzeigen
Basic AC Circuits, 2/E is a step-by-step approach to AC circuit technology for the beginning student, hobbyist, technician, or engineer. The book is built into a series of self-paced, individualized learning goals covering electronics concepts, terms and the mathematics required to fully understand AC circuit problems--simple or complex. Each chapter includes learning objectives, fully-illustrated examples, practice problems and quizzes providing teachers, trainers and students a complete AC technology resource. Basic AC Circuits, 2/E has been a staple of the electronics educational market since 1981, but in the new edition the author has updated the book to reflect changes in technology, especially the test equipment available today.


Basic AC Circuits has been a keystone for curriculum plans around the country for nearly two decades. This book was originally part of the Texas Instruments series published by Sams Publishing.

Provides a fully-revised introduction to AC circuit technology that includes full examples, practice problems and quizzes to measure learning
Includes the mathematics training for AC circuit design that so many technicians and engineers are missing
Written in an easy-to-read and follow format with many illustrations, examples, and hands-on practice.
Basic AC Circuits, Second Edition is a step-by-step approach to AC circuit technology for the beginning student, hobbyist, technician, or engineer. The book is built into a series of self-paced, individualized learning goals covering electronics concepts, terms and the mathematics required to fully understand AC circuit problems--simple or complex. Each chapter includes learning objectives, fully-illustrated examples, practice problems and quizzes providing teachers, trainers and students a complete AC technology resource. Basic AC Circuits has been a staple of the electronics educational market since 1981, but in the new edition the author has updated the book to reflect changes in technology, especially the test equipment available today.Basic AC Circuits has been a keystone for curriculum plans around the country for nearly two decades. This book was originally part of the Texas Instruments series published by Sams Publishing. Provides a fully-revised introduction to AC circuit technology that includes full examples, practice problems and quizzes to measure learning Includes the mathematics training for AC circuit design that so many technicians and engineers are missing Written in an easy-to-read and follow format with many illustrations, examples, and hands-on practice

CHAPTER 1

Introduction to Alternating Current


This chapter is an introductory chapter. Alternating current (ac) is defined and compared to direct current (dc), and the operation of an ac generator is discussed. Time, frequency, and cyclic characteristics of the ac waveform are analyzed with examples provided for each concept.

At the end of this chapter you should be able to:

1. Define an ac waveform and identify dc and ac waveforms from diagrams provided.

2. Describe how an ac generator produces an ac waveform.

3. Identify a cycle and the period of an ac waveform.

4. Given the time of one cycle, calculate the frequency of the waveform.

5. Given the frequency of a waveform, calculate the time of one cycle.

INTRODUCTION


The action of alternating currents in circuits is the subject of this book. The electromagnetic wave displayed on an oscilloscope in Figure 1.1 is an electronic picture of alternating current and is one of the most useful and mysterious of all phenomena known to man. Waveforms such as this are radiating from radio, TV, telephone, and other communication system antennas around the world each day. The alternating current in the antenna is a primary man-made source of electromagnetic waves. Words, music, TV pictures, other sounds are alternating currents amplified by various electronic circuits and applied to antennas to radiate through space and communicate information.

Figure 1.1 An AC Waveform Displayed on an Oscilloscope

It is a textbook designed to provide the general information, theory, and problem-solving techniques required for an analysis of ac circuits from the simplest to the most complex. This first chapter provides an operational definition for ac with comparisons of ac and dc waveforms; theorizes and demonstrates the generation of an ac waveform; and introduces period and frequency relationships of ac waveforms.

AC VOLTAGE AND CURRENT


Definition of Alternating Current

AC is the abbreviation for alternating current. Alternating current is an electrical current which changes in both magnitude and direction. The term, magnitude, refers to the quantitative value of the current in a circuit — in other words, how much current is flowing. The term, direction, refers to the direction current flows in a circuit.

Generating an AC Waveform


The simple dc circuit in Figure 1.2 can be used to simulate alternating current. The circuit consists of a variable dc power supply, a resistor, and a galvanometer. The galvanometer is an ammeter with a center scale value of zero amperes. If current flows in the circuit in a counter-clockwise direction, the meter needle will deflect to the left. If current flows in a clockwise direction, the meter needle will deflect to the right.

Figure 1.2 A Simple DC Circuit with a Galvanometer

With the circuit configuration as shown in Figure 1.3, electron current flow will be in a counter-clockwise direction. If the power supply voltage is increased, the galvanometer needle will deflect to the left to some maximum current value. As the voltage is decreased to zero volts, current flow in the circuit will decrease to zero amperes.

Figure 1.3 Current Flow in a Counter-clockwise Direction

Therefore, a current flow has been predicted which changes in magnitude. This meets one of the two specified criteria for alternating current. To meet the other criterion, a change in direction, the polarity of the battery can be reversed as in Figure 1.4. Notice that current now flows in a clockwise direction.

Figure 1.4 Current Flow in Clockwise Direction

As the power supply voltage is increased, the galvanometer needle deflects to the right to some maximum value. As the voltage is decreased to zero volts, current flow in the circuit decreases to zero amperes.

Plotting an AC Waveform


This alternating current can be represented in graphical form, as shown in Figure 1.5. Notice that the axes of this graph are specified to plot current versus time. Time is plotted on the horizontal, or X axis. Current is plotted on the vertical, or Y axis. The vertical axis is divided into a positive (+) current value above the X axis and a negative (–) current value below the X axis. This polarity designation is used simply to differentiate between direction of current flow.

Figure 1.5 Graph Used to Plot AC Current

For this application, current flow in a counter-clockwise direction will be designated as positive current, and current flow in the opposite, clockwise direction, will be designated a negative current. The polarity and direction selections are arbitrary.

With the circuit connected as in Figure 1.3, current, I, flows in a counter-clockwise direction, with current flow increasing and decreasing. Note that the direction of current stays the same. Only the value of the current is changed. Current in this direction is plotted in the top half of the graph to indicate positive current as shown in Figure 1.6.

Figure 1.6 Current Plotted in Positive Direction

With the battery reversed as shown in Figure 1.4, current now flows in a clockwise direction. The current always flows in the same direction. The magnitude of the current increases and decreases following the magnitude of the applied voltage, and the current is plotted in the negative (–) portion of the graph of Figure 1.7. This indicates negative current or, more precisely, a current that is flowing in a direction opposite to the direction originally chosen for positive current. Note the two distinguishing characteristics of this waveform. First, there is a change in current value — in this example, the change is continuous. Second, the direction of current flow has changed. This change in direction is indicated by the waveform crossing the X axis into the negative half of the graph. If these two criteria are met, the waveform can be categorized as an ac waveform.

Figure 1.7 Current Plotted in Positive and Negative Directions

The particular waveform shown in Figure 1.7 is only one type of an ac waveform, a sine wave. Other ac waveforms which meet the specified criteria for an ac waveform will be introduced later.

AC Voltages


If there is current flow in a circuit, a difference in potential, or voltage, must be present. The voltage, E, that produces an alternating current must change in the same manner as the current as shown by the diagrams in Figure 1.8.

Figure 1.8 Comparison of Alternating Voltage and Alternating Current

The polarity of the voltage must change to cause current to change direction. A voltage that causes an alternating current is called an ac voltage.

Summary of DC and AC Voltages and Currents


The difference between dc and ac voltages and currents can now be summarized.

DC is direct current — a current which flows in only one direction. It can change in magnitude, and if it does, it generally is called pulsating dc. A dc voltage is a voltage that produces a direct current. It does not change in polarity.

AC is alternating current — a current which changes in both magnitude and direction. AC voltage is a voltage that produces an alternating current. It changes in amplitude and polarity. Amplitude is the magnitude or value of an ac voltage.

CONTRASTING DC AND AC WAVEFORMS


A comparison of some different types of dc and ac voltage waveforms should help you understand the differences between the two.

The waveform in Figure 1.9a is a dc waveform because it does not change polarity. Note that the amplitude remains at a constant level. A plot of the current versus time in a circuit with the voltage of Figure 1.9a applied would also be a constant value as a result of a fixed value of dc voltage.

Figure 1.9 a. A DC Waveform; b. A DC Waveform of Polarity Opposite to That of the One in a.

The waveform in Figure 1.9b is also a dc waveform. It has a polarity opposite to that of the waveform in Figure 1.9a, but it too does not change in amplitude.

The waveform in Figure 1.10a is a dc waveform, and it is a pulsating waveform. The entire waveform is in the positive portion of the graph, and never crosses the X axis. If the line graph had crossed the X axis into the opposite half of the graph, and if this voltage were applied to a circuit, then it would have caused the circuit current to change direction, and it would no longer be considered a dc voltage. This is the most important point in distinguishing between dc and ac...

Erscheint lt. Verlag 25.10.2000
Sprache englisch
Themenwelt Kunst / Musik / Theater Design / Innenarchitektur / Mode
Technik Elektrotechnik / Energietechnik
ISBN-10 0-08-049398-X / 008049398X
ISBN-13 978-0-08-049398-5 / 9780080493985
Haben Sie eine Frage zum Produkt?
Wie bewerten Sie den Artikel?
Bitte geben Sie Ihre Bewertung ein:
Bitte geben Sie Daten ein:
PDFPDF (Adobe DRM)
Größe: 8,7 MB

Kopierschutz: Adobe-DRM
Adobe-DRM ist ein Kopierschutz, der das eBook vor Mißbrauch schützen soll. Dabei wird das eBook bereits beim Download auf Ihre persönliche Adobe-ID autorisiert. Lesen können Sie das eBook dann nur auf den Geräten, welche ebenfalls auf Ihre Adobe-ID registriert sind.
Details zum Adobe-DRM

Dateiformat: PDF (Portable Document Format)
Mit einem festen Seiten­layout eignet sich die PDF besonders für Fach­bücher mit Spalten, Tabellen und Abbild­ungen. Eine PDF kann auf fast allen Geräten ange­zeigt werden, ist aber für kleine Displays (Smart­phone, eReader) nur einge­schränkt geeignet.

Systemvoraussetzungen:
PC/Mac: Mit einem PC oder Mac können Sie dieses eBook lesen. Sie benötigen eine Adobe-ID und die Software Adobe Digital Editions (kostenlos). Von der Benutzung der OverDrive Media Console raten wir Ihnen ab. Erfahrungsgemäß treten hier gehäuft Probleme mit dem Adobe DRM auf.
eReader: Dieses eBook kann mit (fast) allen eBook-Readern gelesen werden. Mit dem amazon-Kindle ist es aber nicht kompatibel.
Smartphone/Tablet: Egal ob Apple oder Android, dieses eBook können Sie lesen. Sie benötigen eine Adobe-ID sowie eine kostenlose App.
Geräteliste und zusätzliche Hinweise

Zusätzliches Feature: Online Lesen
Dieses eBook können Sie zusätzlich zum Download auch online im Webbrowser lesen.

Buying eBooks from abroad
For tax law reasons we can sell eBooks just within Germany and Switzerland. Regrettably we cannot fulfill eBook-orders from other countries.

EPUBEPUB (Adobe DRM)

Kopierschutz: Adobe-DRM
Adobe-DRM ist ein Kopierschutz, der das eBook vor Mißbrauch schützen soll. Dabei wird das eBook bereits beim Download auf Ihre persönliche Adobe-ID autorisiert. Lesen können Sie das eBook dann nur auf den Geräten, welche ebenfalls auf Ihre Adobe-ID registriert sind.
Details zum Adobe-DRM

Dateiformat: EPUB (Electronic Publication)
EPUB ist ein offener Standard für eBooks und eignet sich besonders zur Darstellung von Belle­tristik und Sach­büchern. Der Fließ­text wird dynamisch an die Display- und Schrift­größe ange­passt. Auch für mobile Lese­geräte ist EPUB daher gut geeignet.

Systemvoraussetzungen:
PC/Mac: Mit einem PC oder Mac können Sie dieses eBook lesen. Sie benötigen eine Adobe-ID und die Software Adobe Digital Editions (kostenlos). Von der Benutzung der OverDrive Media Console raten wir Ihnen ab. Erfahrungsgemäß treten hier gehäuft Probleme mit dem Adobe DRM auf.
eReader: Dieses eBook kann mit (fast) allen eBook-Readern gelesen werden. Mit dem amazon-Kindle ist es aber nicht kompatibel.
Smartphone/Tablet: Egal ob Apple oder Android, dieses eBook können Sie lesen. Sie benötigen eine Adobe-ID sowie eine kostenlose App.
Geräteliste und zusätzliche Hinweise

Buying eBooks from abroad
For tax law reasons we can sell eBooks just within Germany and Switzerland. Regrettably we cannot fulfill eBook-orders from other countries.

Mehr entdecken
aus dem Bereich
Die Geschichte der Welt in Büchern

von Irene Vallejo

eBook Download (2022)
Diogenes (Verlag)
24,99