Academic Catalog

APEL 123: 3-PHASE AC, TRANSFORMERS, INTERMEDIATE NATIONAL ELECTRICAL CODE

Foothill College Course Outline of Record

Foothill College Course Outline of Record
Heading Value
Effective Term: Fall 2026
Units: 6.5
Hours: 72 lecture, 21 laboratory per quarter (93 total per quarter)
Prerequisite: Per California Code of Regulations, this course is limited to students admitted to the Electrical Apprenticeship Program.
Advisory: Not open to students with credit in APRT 123.
Degree & Credit Status: Degree-Applicable Credit Course
Foothill GE: Non-GE
Transferable: None
Grade Type: Letter Grade (Request for Pass/No Pass)
Repeatability: Not Repeatable

Student Learning Outcomes

  • A student will be able to explain the dangers of transformers.
  • A student will be able to lay out wire sizes for a transformer.
  • A student will be able to perform mathematical calculations for sizing a transformer.
  • A successful student will be able to explain how and why transformers are used.

Description

Continued study of AC theory with an emphasis on 3-phase power. Introduction to transformer design, function, and installation. Introduction to grounding and bonding of transformers. Expanded study of the National Electrical Code pertaining to branch circuits, feeders, and services.

Course Objectives

The student will be able to:

  1. Explain 3-phase AC circuits from basic resistance through impedance and power factor.
  2. Analyze and describe transformer design and function.
  3. Understand how to install the grounding and bonding of a transformer.
  4. Discuss and explain how to use the sections of the National Electrical Code pertaining to branch circuits, feeders, and services.

Course Content

  1. Terms and concepts associated with 3-phase AC power
    1. Current and voltage sine waves to demonstrate phase relationships
    2. Maximum, effective (RMS), average, and peak-to-peak voltage and current
    3. Inductance
    4. Capacitance
  2. Transformer design and function
    1. Main purposes of transformers
    2. Types of transformers
    3. Proper sizing of transformers
    4. Proper wiring and installation of transformers
  3. Use of the National Electric Code
    1. Discussion of conductor ampacity
    2. Discussion of conductor and insulator materials
    3. Effects of heat on insulators
    4. Sizing and typing of conductors
    5. Conductor installation techniques

Lab Content

  1. Students will demonstrate the proper safety techniques in the testing of voltage, current, and power.
  2. Students will demonstrate the proper installation of different type of transformers.
  3. Students will use the National Electric Code book to determine the proper sizing and selection of conductors.

Special Facilities and/or Equipment

1. Laboratory with electrical tools and equipment.
2. When taught as a virtual section, on-going access to computer with software and hardware capable of running video conferencing applications (e.g., Zoom).

Method(s) of Evaluation

Methods of Evaluation may include but are not limited to the following:

Results of written quizzes and average of four tests
Results of hands-on projects and homework
Results of class participation
Maintenance of a student's workbook with questions drawn from text

Method(s) of Instruction

Methods of Instruction may include but are not limited to the following:

Lecture
Lab assignments
Group discussion
Class demonstrations

Representative Text(s) and Other Materials

Electrical Training Alliance. Syllabus for Second Year Core Curriculum. 2022.

Delmar Cengage Learning in Partnership with the NJATC. AC Theory, 3rd ed.. 2011.

National Joint Apprenticeship and Training Committee. Code Calculations 2023 NEC. 2023.

Callanan, Michael I., and Bill Wusinich. Electrical Systems 2023 NEC. 2023.

IBEW. By-Laws. 2019.

IBEW. Constitution. 2016.

NFPA. The National Electrical Code (NFPA 70). 2023.

Miller, Charles R.. Ugly's Electrical References, 2023 ed.. 2023.

American Technical Publishers, Inc. in Partnership with NJATC. Transformer Principle and Applications. 2006.

These are the standard electrical textbooks/workbooks used for this course. Although some are older than 5 years, they are the most current books used when teaching this course.

Types and/or Examples of Required Reading, Writing, and Outside of Class Assignments

  1. Read chapters 6-10 in the course textbook, AC Theory (3rd ed).
  2. Prepare an electrical diagram using the principles of Ohm's Law.
  3. Prepare a list of the various types of transformers used in AC circuits.

Discipline(s)

Electricity