Online Courses

Discount Packages

Ethics, Laws and Rules

Live Webinars

Video Presentations

Interactive Courses

OH Timed & Monitored

Courses by Provider

Unit Protection of Feeders

COURSE NO: E04-041
Unit Protection of Feeders
Course Highlights

This online engineering PDH course presents the concepts of electrical unit protection and their particular applications to high voltage feeders.


The graded overcurrent protection design, though quite simple, do not meet all the protection demands of an electrical power system. Application issues are experienced for two reasons: firstly, acceptable grading cannot be accomplished for a complex electrical system, and secondly, the protection adjustments may lead to maximum operating times that are excessive and cannot stop faults.


These issues are directed to the unit protection concept. This concept means that parts of the electrical system are separately protected without reference to other parts of the electrical system. One unit protection concept is widely known as ‘Differential Protection’. Foundation of this principle is to detect the difference in currents between the incoming and outgoing terminals of the protected element. Other unit protection concepts can be based on directional comparison, distance tele-protection arrangements or phase comparison unit protection.


This 4 PDH online course is suitable for electrical engineers with a desire to understand the fundamentals of feeder unit protection. Upon successful completion engineers will be able to address basic feeder unit protection terminology, concepts, applications and arrangements. 

Learning Objectives

This PE continuing education course is intended to provide you with the following specific knowledge and skills:

  • Basic unit protection concepts involving circulating current, balanced voltage, direction convention, transient instability, bias etc.
  • Summation arrangements
  • Electromechanical, static and numerical/digital unit protection systems
  • Relay time synchronization
  • Current differential and phase comparison schemes
  • Carrier unit protection schemes 
Course Document

In this professional engineering CEU course, you need to review the course document titled, “Unit Protection of Feeders”.

To view, print and study the course document, please click on the following link(s):
Unit Protection of Feeders (1.4 MB)
Course Quiz

Once you complete your course review, you need to take a multiple-choice quiz consisting of twenty five (25) questions to earn 4 PDH credits. The quiz will be based on the entire document.

The minimum passing score is 70%. There is no time limit on the quiz, and you can take it multiple times until you pass at no additional cost.
Certificate of Completion

Upon successful completion of the quiz, print your Certificate of Completion instantly. (Note: if you are paying by check or money order, you will be able to print it after we receive your payment.) For your convenience, we will also email it to you. Please note that you can log in to your account at any time to access and print your Certificate of Completion.

To buy the course and take the quiz, please click on: