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

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.

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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.

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Audience

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

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Agenda

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

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Learning Outcomes

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.

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Course Preparation

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

• acSELerator QuickSet SEL-5030 Software (include all device drivers during installation).
• SEL-C662 USB driver.
• SEL-487B instruction manual.

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