A/C Circuits (EET1025C)

Course Description

EET1025C – A/C Circuits is a combined lecture and laboratory course in the Electronic Engineering Technology program. Students study the behavior of electrical circuits driven by alternating voltage sources, with emphasis on sinusoidal waveforms and steady-state AC circuit analysis. Topics include resistive and reactive passive elements, phasor techniques, series and parallel RLC networks, power, resonance, magnetic circuits, and ideal transformers. Extensive laboratory experience reinforces theoretical concepts through hands-on measurement and circuit construction using modern test equipment. This course prepares students for a related technical certification and serves as a foundation for advanced electronics coursework.

Learning Outcomes

Required Outcomes

Upon successful completion of this course, students will be able to:

• Describe and mathematically characterize sinusoidal waveforms, including amplitude, frequency, period, phase, and RMS values.
• Convert time-domain sinusoidal quantities to phasor-domain representations and vice versa.
• Compute inductive and capacitive reactance and represent impedance in rectangular and polar (complex) form.
• Analyze series and parallel AC circuits containing resistors, inductors, and capacitors using phasor methods.
• Apply Kirchhoff's Voltage and Current Laws (KVL/KCL) to AC networks.
• Calculate AC power quantities including apparent power, real power, reactive power, and power factor.
• Analyze series and parallel resonant circuits and determine resonant frequency, bandwidth, and Q factor.
• Explain the operating principles of ideal transformers and calculate voltage, current, and impedance transformation ratios.
• Analyze magnetic circuits, including concepts of reluctance, flux, and magnetomotive force.
• Use modern electronic test equipment — including oscilloscopes, function generators, and multimeters — to measure AC circuit quantities accurately.
• Construct and test AC circuits in the laboratory and compare measured results to theoretical predictions.

Optional Outcomes

Depending on institutional emphasis, students may also:

• Apply network theorems (Thevenin's, Norton's, Superposition) to AC circuits.
• Perform nodal and mesh analysis for multi-loop AC networks.
• Analyze transient responses of RC, RL, and RLC circuits to step inputs.
• Introduce basic concepts of passive filters (low-pass, high-pass, band-pass, band-stop).
• Use circuit simulation software (e.g., Multisim, LTspice) to model and verify AC circuit behavior.
• Apply basic Fourier concepts to describe non-sinusoidal periodic waveforms.
• Introduce concepts of polyphase (three-phase) systems and their applications.

Major Topics

Required Topics

• Sinusoidal Waveforms and AC Fundamentals – Sine wave parameters (amplitude, frequency, period, phase angle, DC offset); peak, peak-to-peak, average, and RMS values; generation of AC voltage.
• Phasors and Complex Numbers – Rectangular and polar forms; arithmetic operations with complex numbers; phasor diagrams; conversion between time-domain and phasor-domain representations.
• Capacitors and Capacitive Reactance – Capacitor behavior in AC circuits; capacitive reactance (X_C) as a function of frequency; voltage-current phase relationships.
• Inductors and Inductive Reactance – Inductor behavior in AC circuits; inductive reactance (X_L) as a function of frequency; voltage-current phase relationships.
• Impedance and Admittance – Complex impedance of R, L, and C elements; series and parallel impedance combinations; admittance and susceptance.
• Series AC Circuits – Series RL, RC, and RLC circuit analysis; phasor voltage diagrams; voltage divider rule applied to AC circuits.
• Parallel AC Circuits – Parallel RL, RC, and RLC circuit analysis; phasor current diagrams; current divider rule applied to AC circuits.
• AC Power – Instantaneous, average (real), reactive, and apparent power; power factor and power factor correction; power triangle.
• Series and Parallel Resonance – Resonant frequency; bandwidth; quality factor (Q); selectivity; practical applications of resonant circuits.
• Magnetic Circuits and Mutual Inductance – Magnetic flux, flux density, magnetomotive force, reluctance; Faraday's and Lenz's laws; mutual inductance and coupling coefficient.
• Transformers – Ideal transformer operation; turns ratio; voltage, current, and impedance transformation; transformer efficiency; practical applications.
• Laboratory: Test Equipment and Measurement – Oscilloscope operation and waveform interpretation; function generator use; DMM AC measurements; proper measurement technique and safety.
• Laboratory: Circuit Construction and Verification – Building and testing series/parallel RLC circuits; measuring phase relationships; verifying resonance; transformer experiments.

Optional Topics

• AC Network Theorems – Thevenin's and Norton's equivalents for AC circuits; superposition principle applied to AC sources.
• Nodal and Mesh Analysis (AC) – Node-voltage and mesh-current methods extended to phasor domain.
• Transient Analysis – Natural and step responses of first-order (RC, RL) and second-order (RLC) circuits; time constants.
• Passive Filters – Low-pass, high-pass, band-pass, and band-stop filter characteristics; cutoff frequency; Bode plot introduction.
• Circuit Simulation – Using SPICE-based tools (Multisim, LTspice) to simulate and verify AC circuit performance.
• Non-Sinusoidal Waveforms and Basic Fourier Analysis – Decomposition of square, triangle, and complex waveforms into harmonic components.
• Introduction to Polyphase Systems – Three-phase voltage generation; balanced three-phase circuits; wye and delta configurations.

Resources & Tools

• Textbooks: AC Electrical Circuit Analysis (Fiore, open-access); Introductory Circuit Analysis (Boylestad); Electronics Fundamentals (Floyd & Buchla)
• Open Educational Resources: All About Circuits (allaboutcircuits.com) – AC volume; Engineering LibreTexts – Electrical Engineering; Florida Virtual Campus (FLVC) course materials
• Laboratory Equipment: Digital oscilloscope, function/signal generator, digital multimeter (DMM), LCR meter, variable AC power supply, breadboards, component kits (R, L, C, transformers)
• Simulation Software: NI Multisim (industry-standard); LTspice (free); Tinkercad Circuits (browser-based)
• Reference Standards: IEEE and NFPA 70 (National Electrical Code) for safety awareness; IPC standards for circuit assembly

Career Pathways

EET1025C provides foundational skills applicable to a broad range of careers in electronics and electrical technology, including:

• Electronics Technician – Installation, testing, and maintenance of electronic equipment and systems
• Electrical/Electronics Engineering Technologist – Supporting engineers in design, prototyping, and troubleshooting
• Biomedical Equipment Technician (BMET) – Servicing electronic medical instruments
• Telecommunications Technician – AC signal analysis is foundational to communication systems
• Power/Utility Technician – AC power distribution, transformer maintenance, power factor correction
• Industrial Maintenance Technician – Motor drives, control panels, and industrial AC systems
• Avionics Technician – Aircraft electrical and electronic systems

This course supports progression toward Associate in Science (A.S.) degrees in Electronic Engineering Technology and related Applied Technology certificates. Graduates may pursue industry certifications such as the Electronics Technicians Association (ETA) Associate CET or CompTIA Electronics Technician credentials.

Special Information

Combined Lecture and Laboratory ("C" designator): Per Florida's Statewide Course Numbering System, the "C" suffix indicates this course meets as a combined lecture and laboratory in the same location and time period. Students are expected to complete both written/analytical work and hands-on laboratory exercises as integrated components of the same course.

Certification Preparation: This course prepares students for industry-recognized technical certifications in electronics technology, including the ETA International Associate Certified Electronics Technician (CET) exam. Laboratory competencies in measurement and circuit construction directly align with certification practical skill requirements.

Safety: Students must observe standard electrical safety practices throughout all laboratory activities, including proper handling of energized circuits, use of appropriate personal protective equipment (PPE), and adherence to institutional laboratory safety policies.