html{display:none} CBT 104: Understanding SEL Relay Logic | Schweitzer Engineering Laboratories

CBT 104: Understanding SEL Relay Logic

Single-User Training

PDHs: 4

Course Base Fees: $0


Course Information

CBT licenses will expire one year from the purchase date.

Confused by logic diagrams and SELOGIC control equation settings? Need to be able to test relay logic before it goes in service? In CBT 104, you will learn how to read, set, and test SEL relay logic as you identify Relay Word bits and SELogic operators and visually interpret diagrams. Learn to equate relay protection functions with logic diagrams, and see how relay logic assigns protective elements to output contacts for control, monitor, and trip functions.

This course is designed as a half-day program but is self-paced.


This course is intended for engineers, technicians, and consultants new to SEL relays or logic programming.


  • Introduction
  • Relay Logic Basics
  • Visualizing Logic
  • Settings and Logic
  • Testing Relay Logic
  • Event Analysis and Logic
  • Knowledge Check

Course Objectives

At the conclusion of this course, students can:

  • Correlate Relay Word bits with settings and protection functions.
  • Visually identify logic components.
  • Differentiate between settings and logic.
  • Analyze logic diagrams.
  • Interpret logic using a relaying schematic.
  • Use acSELerator QuickSet SEL-5030 Software to convert and visualize logic.
  • Diagnose problems using event data and logic.

Student Background and Knowledge

Before you attend this class, we recommend that you have a basic knowledge of power systems.

Available Courses

Single-User Training

SEL University Training Question



Course Preparation

Additional information is on the Course Policies page.