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CCOG for ELT 204 Spring 2024

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Course Number:
ELT 204
Course Title:
Adjustable Speed Drives
Credit Hours:
2
Lecture Hours:
10
Lecture/Lab Hours:
20
Lab Hours:
0

Course Description

Covers theory, operation, installation, and maintenance of adjustable speed motor drives. Introduces drive applications and selection for use in industrial, utility, and commercial structures. Prerequisites: Placement in MTH 20 or higher; (WR 80 or ESOL 252) and (RD 80 or ESOL 250) or equivalent placement. Audit available.

Addendum to Course Description

This class covers the current year code book in these areas: NEC Article 430 - Motors, Motor Circuits, and Controllers Figure 430.1 , 430.2 - Definitions: CONTROLLER, 430.6 - Ampacity & Motor Rating Determination (A) (1), 430.32 - Motor and Branch-Circuit Overload Protection, 430.52 - Motor and Branch-Circuit Short-Circuit & Ground Protection Individual Motors, 430.53 - (C) Motor and Branch-Circuit Short-Circuit & Ground Protection Other Group Installations, 430.43 - Automatic Restarting,. 430-120 - .131 Adjustable-Speed Drive Systems

Intended Outcomes for the course

Upon completion of the course students should be able to:

  • Identify the concept of force, inertia, speed, and torque.
  • Identify the difference between work and power.
  • Identify the construction of a squirrel cage motor.
  • Identify the nameplate information of an AC motor and how it applies to an AC drive.
  • Apply an understanding of the operation of a three-phase rotating magnetic field.
  • Calculate synchronous speed, slip, and rotor speed.
  • Identify the difference between volts, cycle, torque, and current.
  • Identify the basic construction and operation of a pulse width modulation (PWM)  type AC drive.
  • Identify the characteristics of constant torque, constant HP, and variable torque applications.
  • Apply understanding of direct-current motors and their use in a variety of industries.
  • Apply an understanding of different methods of repeated closure of a circuit.
  • Identify the installation of motor drives and how to calculate the size required.

Course Activities and Design

A lecture-laboratory course in which the student may come from a wide variety of occupations. The emphasis of the course will depend on Instructor analysis of the needs of the students. Laboratory activities will utilize electrical test equipment to understand the operation of adjustable speed drives.

Outcome Assessment Strategies

Procedures will be discussed at the first class session and the instructor's grading policy will be referenced on the class syllabus. Assessment will be based on attendance, participation, homework, lab activities, assignments, short quizzes and written examination.

Course Content (Themes, Concepts, Issues and Skills)

  • Identify the concept of Force, Inertia, Speed & Torque.
  • Identify the difference between work & power.
  • Identify the construction of a squirrel cage motor.
  • Identify the nameplate information of an AC motor, & how it applies to an AC drive.
  • Apply understanding of the operation of a three-phase rotating magnetic field.
  • Calculate synchronous speed, slip, & rotor speed.
  • Identify the difference between volts/HZ., torque, and current.
  • Identify the basic construction & operation of a PWM (Pulse width modulation) type AC drive.
  • Identify the characteristics of constant torque, constant HP, and variable torque applications.
  • Apply understanding of direct-current motors and their use in a variety of industries.
  • Apply understanding of several methods of repeated closure of a circuit.
  • Identify the installation of motor drives and how to calculate the size required.