# ME301: Measurement & Experimentation Laboratory

Unit 3: Electrical Circuits and Measurements   A review of basic circuit principles and measurements is included here for completeness, but you should refer to PHYS102: Introduction to Electromagnetism for a discussion of the fundamental physics.   In this unit, you will review elementary concepts of circuit analysis for utility in signal transduction, conditioning, and measurement.

Note: Much of the material in Units 3 and 4 are interdependent and refer you to discussion available in the resource “All About Circuits”; you are encouraged to peruse that resource in full at your own pace if you do are not familiar enough with concepts in electrical engineering to understand the material as it is presented here.  In addition, many of the sections in “All About Circuits” contain example problems that you should follow and review for particular emphasis.

Note: There is a review quiz for both Units 3 and 4 at the end of Unit 4.

This unit should take you 13 hours to complete.

☐    Subunit 3.1: 1 hour

☐    Subunit 3.2: 3 hours

☐    Subunit 3.3: 3 hours

☐    Subunit 3.4: 2 hours

☐    Subunit 3.5: 1 hour

☐    Subunit 3.6: 3 hours

Unit3 Learning Outcomes
Upon successful completion of this unit, the student will be able to:

• Apply Kirchoff’s laws to circuit analysis.
• Analyze circuits for alternating and direct current characteristics.
• Predict and measure current and voltage for circuits.
• Predict the performance of circuit elements including resistors, capacitors, voltage sources, current sources, inductors, filters, diodes, and amplifiers.

3.1 Standards and Units   - Reading: All About Circuits: “Volume 1, Chapter 1: Basic Concepts of Electricity” Link: All About Circuits: “Volume 1, Chapter 1: Basic Concepts of Electricity” (PDF)

Instructions: Read Chapter 1.  You may skim this material if you are already familiar with it, but it is light, non-mathematical reading.  You may benefit from the analogy of fluid flow and electrical flow. To view as a PDF, click the PDF link in the top right corner.

3.2 Elementary Circuit Elements   3.2.1 Resistors   - Reading: All About Circuits: “Volume 1, Chapter 2: OHM’s LAW” Link: All About Circuits: “Volume 1, Chapter 2: OHM’s LAW” (PDF)

Instructions: Read Chapter 2.  Again, you may skim the chapter if you are already familiar with the concepts.  You may wish to practice with calculations of power, current, voltage, and resistance. To view as a PDF, click the PDF link in the top right corner.

3.2.2 Inductors   - Reading: All About Circuits: “Volume 2, Chapter 3: Reactance and Impedance – Inductive” Link: All About Circuits: “Volume 2, Chapter 3: Reactance and Impedance -- Inductive” (PDF)

Instructions: Read Chapter 3.  You have already read Chapter 1 on Basic AC Theory, but you may wish to reread it and then refresh your memory by reading Chapter 2 on complex numbers. To view as a PDF, click the PDF link in the top right corner.

3.2.3 Capacitors   - Reading: All About Circuits: “Volume 2, Chapter 4: Reactance and Impedance – Inductive” Link: All About Circuits: “Volume 2, Chapter 4: Reactance and Impedance -- Inductive” (PDF)

Instructions: Read Chapter 4.  You may find the section on “Capacitor Quirks” mildly amusing.  The text does not emphasize the units, but you may wish to look at the size of typical capacitors you might find in electrical appliances. To view as a PDF, click the PDF link in the top right corner.

3.3 Elementary Circuit Principles   3.3.1 Circuit Analysis   - Reading: All About Circuits: “Volume 1, Chapter 6: Divider Circuits and Kirchoff’s Laws,” “Voltage Divider Circuits,” “and “Current Divider Circuits” Link: All About Circuits: “Volume 1, Chapter 6: Divider Circuits and Kirchoff’s Laws:” (PDF) “Voltage Divider Circuits” and “Current Divider Circuits”

Instructions: A firm grasp of the concept behind and applications of Kirchoff’s laws is a must.  You may wish to practice by following along with the calculations in this section. To view as a PDF, click the PDF link in the top right corner.

3.3.2 Current Relationships   - Reading: All About Circuits: “Volume 1, Chapter 6: Kirchoff’s Current Law” Link: All About Circuits: “Volume 1, Chapter 6: Kirchoff’s Current Law” (PDF)

Instructions: Read the linked section above and practice calculations as illustrated in the reading. To view as a PDF, click the PDF link in the top right corner.

3.3.3 Voltage Relationships   - Reading: All About Circuits: “Volume 1, Chapter 6: Kirchoff’s Voltage Law” Link: All About Circuits: “Volume 1, Chapter 6: Kirchoff’s Voltage Law” (PDF)

Instructions: Read the linked section above and practice calculations as illustrated in the reading. To view as a PDF, click the PDF link in the top right corner.

3.4 Elementary Measurements   - Reading: All About Circuits: “Volume 6, Chapter 2: Basic Concepts and Test Equipment” Link: All About Circuits: “Volume 6, Chapter 2: Basic Concepts and Test Equipment” (PDF)

Instructions: Read the linked section above.  At this stage, you should skim through the material and gather materials together for exercises that will be performed later. To view as a PDF, click the PDF link in the top right corner.

3.5 Nonlinear and Composite Elements   3.5.1 Diodes   - Reading: All About Circuits: “Volume 3, Chapter 3: Diodes and Rectifiers” Link: All About Circuits: “Volume 3, Chapter 3: Diodes and Rectifiers” (PDF)

Instructions: Read the section linked above and perform measurements as possible.  You may skip the section on SPICE. To view as a PDF, click the PDF link in the top right corner.

3.5.2 Signal Amplifiers   - Reading: All About Circuits: “Volume 3, Chapter 1: Amplifiers and Active Devices” Link: All About Circuits: “Volume 3, Chapter 1: Amplifiers and Active Devices”(PDF)

Instructions: Read the linked section above.  You may wish to pay particular attention to the definition and use of the unit decibel or dB and work along with the examples. To view as a PDF, click the PDF link in the top right corner.

Instructions: Read the linked section and ask yourself why analog filters are still useful in modern, digital systems. To view as a PDF, click the PDF link in the top right corner.

3.6 Exercises   3.6.1 Voltage and Current Measurement in Simple Circuits   3.6.1.1 Voltmeter Usage   - Reading: All About Circuits: “Volume 6, Chapter 2: Voltmeter Usage” Link: All About Circuits: “Volume 6, Chapter 2: Voltmeter Usage” (PDF)

Instructions: Read the linked section above and perform measurements as possible. To view as a PDF, click the PDF link in the top right corner.

3.6.1.2 Ohmmeter Usage   - Reading: All About Circuits: “Volume 6, Chapter 2: Ohmmeter Usage” Link: All About Circuits: “Volume 6, Chapter 2: Ohmmeter Usage” (PDF)

Instructions: Read the linked section above and perform measurements as possible. To view as a PDF, click the PDF link in the top right corner.

3.6.1.3 Ammeter Usage   - Reading: All About Circuits: “Volume 6, Chapter 2: Ammeter Usage” Link: All About Circuits: “Volume 6, Chapter 2: Ammeter Usage” (PDF)

Instructions: Read the linked section above and perform measurements as possible. To view as a PDF, click the PDF link in the top right corner.