Academic Catalog

APEL 126: MOTORS; MOTOR CONTROL; RELAYS & RELAY LOGIC

Foothill College Course Outline of Record

Foothill College Course Outline of Record
Heading Value
Effective Term: Fall 2026
Units: 5.5
Hours: 57 lecture, 36 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 126.
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 line and wiring diagram construction of motor control circuits.
  • A student will be able to explain the logic of control circuits.
  • A student will be able to explain the practical applications of motor controls with AC and DC motors and how they are used for control commercial and industrial equipment.
  • A student will be able to introduce manual and automatic motor control fundamentals using relays, contactors, magnetic motor starters and control components.
  • A student will be able to work on or around mechanical and electrical equipment.
  • A successful student will be able demonstrate use of person protective equipment.
  • A successful student will be able to Identify lock out/tag out procedures.
  • A successful student will be able to identify motor controls symbols.

Description

A study of different motor types and controls with emphasis on protection of the motor and conductors. Study of different relays in the electrical industry, including types of applications.

Course Objectives

The student will be able to:

  1. Compare different types of motors, their construction and usage.
  2. Discuss motor controls.
  3. Explain and read schematic drawings.
  4. Understand the different types of relays and their applications.

Course Content

  1. Motors and their construction
    1. Function, operation, and characteristics of various types of motors (AC, DC, dual voltage repulsion, universal, 3-phase, squirrel cage, synchronous)
    2. Physical parts of various motors
    3. Utilize information sheets, plans, schematics, and motor nameplates to gain information
    4. Motor losses
    5. Starting and operating characteristics
    6. Methods to identify windings in DC motor
    7. Means for providing field failure, current limit, voltage, and speed control
    8. Block diagrams to demonstrate power supplies, armature, field, and control features
    9. Torque, locked rotor current, no-load speed, and slip
    10. Reasons for low voltage starting
    11. Function, operation, and characteristics of stepping motors
    12. Proper techniques for motor installations
    13. Necessary calculations for electrical requirements per code
    14. Correct power factor
    15. Proper wire type and size
    16. Appropriate connections
    17. How various motors can be made to run at a different speed or direction
    18. Schematics
    19. Connections top reverse or change direction
  2. Function, operation, and characteristics of motor controllers, circuits, and devices
    1. Ways and means of starting and stopping motors
    2. Operation of a magnetic coil
    3. Use of magnetic starters and controllers
    4. Correct sizing of magnetic starters and controllers
    5. Difference between starters and contactors
    6. Function, operation, and characteristics of overload protective devices
    7. Schematics for various control circuits
    8. Two-wire control
    9. Three-wire control circuits
    10. Interlocking methods
    11. Reversing and sequential controllers
    12. Jogging, inching, plugging
    13. Multiple start-stop controls and selector switches
    14. Phase failure relays
    15. Various manual and automatic speed control techniques
    16. Function, operation, and characteristics of variable frequency drive systems
    17. Function, operation, characteristics, and installation procedures, programmable logic controllers
    18. Ladder diagrams
    19. Function, operation, and characteristics of timers, counters, sequencers
    20. Utilize appropriate manual and information for start-up, maintenance, and testing
    21. Utilize schematics for manual starters, automatic starters, speed regulators, and controllers
  3. Reading motor control drawings
    1. Two-wire control circuits
    2. Three-wire motor control
    3. Controls application
    4. Push-button interlocks
    5. Mechanical interlocks
    6. Jogging and plugging controls
    7. DC and AC applications
    8. Schematic, including switches and relays
    9. Function, operation, and characteristics of electronic sensor and pilot devices
    10. Function, operation, and characteristics of control transformers

Lab Content

  1. Student will identify the different parts of a motor.
  2. Student will identify different control devices for motors.
  3. Student describe the sequence of operation of a motor control drawing.
  4. Student will be able to terminate a 3-phase motor.
  5. Student will be able to properly configure motor windings.
  6. Student will be able to read and interpret a ladder diagram.
  7. Student will be able to build a motor control circuit based on a ladder diagram.

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 exams
Results of hands-on projects and homework
Results of class participation

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

Rocks, Gary J., and Glen A. Mazur. Electrical Motor Controls for Integrated Systems, 5th ed.. 2014.

Mike Holt Enterprises. Electrical Exam Preparation. 2020.

Electrical Training Alliance. Syllabus for Fourth Year Core Curriculum. 2025.

These are the standard Electrical textbooks/workbooks used for this course. Although some are older than five 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 Syllabus for Fourth Year Core Curriculum.
  2. Prepare a diagram of the sequence of operations for a motor control drawing.

Discipline(s)

Electricity