Print this page Standard AC System Voltages (600 V and Less)
David A. Snyder, P.E.
Course Outline
This 1 PDH course includes descriptions and illustrations of the different types of transformer secondary connections for standard single-phase and three-phase power sources.
This course includes a multiple-choice quiz at the end, which is designed to enhance the understanding of the course materials.
Learning Objective
At the conclusion of this course, the student will:
- Understand the various types of transformer secondary connections for standard single-phase and three-phase AC systems;
- Understand the relationship between wye (line-to-neutral) and delta (line-to-line) voltages in three-phase AC systems;
- Understand “high leg” delta connections; and
- Understand 120/208Y single-phase connections.
Intended Audience
Any engineer, designer, contractor, or technician who is involved in the selection, operation, and trouble-shooting of electrical equipment and components will benefit from this course. It is assumed that the Reader is familiar with vector representation of three-phase voltages and currents.
Benefit to Attendees
Upon successful completion of the course, the reader will have a thorough understanding of the various types of standard AC system voltages, arrangements, and connections.
Course Introduction
There are at least a half-dozen different standard AC voltage systems that electrical personnel have to be familiar with in their day-to-day activities. This course explains how these and other voltages are obtained from the secondary connections of transformers and provides scaled illustrations on which the voltage relationships can be directly measured.
Course Content
This course content is in the following PDF document:
Standard AC System Voltages (600 V and Less)
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Course Summary
We are all familiar with the 120/240 V single-phase service to our homes, but why is the utilization voltage often called 115 VAC and 230 VAC? Why is 277 VAC the line-to-neutral voltage in a 480Y/277V system? What is a “high-leg” delta system? These and many other questions will be answered in this course.
Quiz
Once you finish studying the above course content, you need to take a quiz to obtain the PDH credits.
DISCLAIMER: The materials contained in the online course are not intended as a representation or warranty on the part of PDH Center or any other person/organization named herein. The materials are for general information only. They are not a substitute for competent professional advice. Application of this information to a specific project should be reviewed by a registered architect and/or professional engineer/surveyor. Anyone making use of the information set forth herein does so at their own risk and assumes any and all resulting liability arising therefrom.
