ELTR 1120 Syllabus

Subject Code

ELTR

Course Number

1120

Course Title

Variable Speed/Low Voltage Controls

Prerequisites

Provisional admission

Corequisites

Terms Offered

Offered Spring

Credit Hours

(1-2-2)

Course Description

This course introduces different types of electric motor controls, reduced voltage starting, and applications. Instructors will emphasize motor types, controller types, and applications. This course also includes information on wye and delta motor connections, part wind, autotransformer, adjustable frequency drives and other applications, and oscilloscopes and their operation. Topics also include reduced voltage starting, reduced voltage motor connections, and adjustable frequency drive. Students must pay a $30 supply fee when registering for this course.

Course Outcomes

Types of Reduced Voltage Starting
Order Description

1 Diagram the primary resistance starter and motor connections and wiring.

2 Diagram the auto-transformer starter and motor connections and wiring.

3 Diagram the wye-delta starter and motor connections and wiring.

4 Diagram the solid state starter and motor connections and wiring.

Reduced Voltage Motor Connections
Order Description
1 Install and operate a primary resistance controller and connected motor.

2 Install and operate an auto-transformer controller and connected motor.

3 Install and operate a wye-delta controller and connected motor.

4 Install and operate a solid state controller and connected motor.

Adjustable Frequency Drive
Order Description

1 Describe the use of an adjustable speed activator with an induction motor.

2 Describe the use of frequency connectors with an induction motor.

3 Describe the applications of a speed regulator and volts per cycle regulator.
4 Describe how the Leblanc, Karmer, and Scherbius systems or speed control feed rotor power

back in the line or provide additional motor torque.
5 Use the formula: F=Required Rev.Min x No. of piles to obtain modified frequency.