html{display:none} APP 487B: SEL-487B Bus Differential and Breaker Failure Relay | Schweitzer Engineering Laboratories

APP 487B: SEL-487B Bus Differential and Breaker Failure Relay

PDHs: 15

Course Base Fees: $1,000*
* Plus Applicable Tax


Course Information

This is a two-day course.

Course Base Fees: $1,000 USD

Students in the APP 487B course explore implementation of station-wide, low-impedance current differential protection and integrated circuit breaker failure detection using the SEL-487B Bus Differential and Breaker Failure Relay. Single- and three-relay applications for both basic and complex busbar arrangements are covered. Backup overcurrent protection, event recording, automation, and time-synchronization capabilities are discussed. Students will work directly with the SEL‑487B Relay, performing hands-on communications, settings, and testing.

Course topics include:

  • Busbar differential protection.
  • Bus coupler configurations and settings.
    • Coupler security logic.
    • Bus coupler faults and accelerated tripping.
  • Advanced zone selection logic and CT requirements.
  • Open-phase detection and breaker failure protection.
  • Phase, negative-sequence, and zero-sequence voltage supervision.
  • Disconnect and breaker status monitoring.
  • Multiple event report analysis and high-resolution Sequential Events Recorder (SER) reports.
  • Settings management and event analysis using acSELerator QuickSet SEL-5030 Software.
  • Direct transfer trip with Mirrored Bits communications.


This course is designed for utility and industrial protection engineers and power system consultants.


Day 1

  • Relay Overview
  • Front-Panel HMI and Hardware Overview
  • Relay Communications
  • SELogic Control Equations
  • Single-Zone Application Example
  • Alias Settings
  • Global Settings

Day 2

  • Zone Configuration Settings
  • Protection Settings
  • Output Configuration and Settings
  • Front-Panel Settings
  • Event Report Retrieval and Analysis
  • Dual-Zone Application Example
  • Breaker Failure Protection

Course Objectives

At the conclusion of this course, students can:

  • Determine busbar classifications and interpret station diagrams.
  • Establish a busbar protection philosophy.
  • Describe differential bus protection schemes, principles, and performance standards.
  • Determine input information needed for protection zone selection.
  • Assign relay inputs using SELogic control equations and alias names.
  • Develop settings for different busbar configurations.
  • Program front-panel LEDs to indicate latch bit status.
  • Access relay status and event history for multiple relays.

Student Background and Knowledge

Before you attend this class, we recommend that you:

  • Complete CBT 101: Introduction to SEL Relays (highly recommended) OR have basic familiarity with protective relaying, SELogic control equations, QuickSet, front-panel controls, and relay testing.
  • Have the ability to set up a communications session.

Available Courses

Request onsite training for your company.

Get Quote

SEL University Training Question



Course Preparation

Install or update the following software/files on the laptop you are bringing to class:

Please ensure that your laptop does not have any installation blocks before you come to class.

Additional information is on the Course Policies and FAQ pages.