APP 87: SEL-387 and SEL-587 Percentage-Restrained Differential Relays

APP 87 provides comprehensive application training for the SEL-387 and the SEL‑587 percentage-restrained differential relays, which offer sensitive, high-speed protection for transformer, machine, and bus differential applications. Students (in groups of two) gain hands-on experience in communicating, setting, metering, monitoring, retrieving and analyzing event reports, and performing control functions by working directly with SEL-387 and SEL-587 Relays. Course topics include:

• Three-phase, dual-slope percentage-restrained differential elements.
• Tap, phase, and zero-sequence compensation for transformer differential applications.
• Harmonic restraint or blocking for transformer inrush and overexcitation.
• Unrestrained differential element.
• Multiple phase, negative-sequence, and zero-sequence overcurrent elements.
• Restricted earth fault ground differential.
• SELogic control equations.

Audience

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

Agenda

Day 1

• Introduction to Transformer Differential Protection
• SEL-587 Relay Overview and Model Options
• Introduction to SELogic Control Equations
• Introduction to acSELerator QuickSet SEL-5030 Software and SEL-AMS
• SEL-587 Differential Settings (includes a class exercise)
• SEL-587 Differential Element Testing Introduction
• Hands-On Differential Element Testing
• SEL-587 Hands-On Analysis

Day 2

• SEL-387 Relay Overview
• SEL-387 Front-Panel Targets and Display
• SEL-387 Hands-On Meter Checks
• SEL-387 Differential Element Settings (includes a class exercise)
• SEL-387E Hands-On Differential Elements
• SEL-387 Hands-On Analysis
• Introduction to Volts/Hertz Element (includes class exercises)
• Additional SEL-387E Hands-On Testing

Course Objectives

At the conclusion of this course, students can:

• Explain the application considerations of differential protection.
• Apply internal or external phase shift and zero-sequence compensation using two different setting methods in both relays.
• Use SELogic control equations to customize the relay logic to meet your application requirements.
• Analyze Sequential Events Recorder (SER) reports and generate COMTRADE files from event reports.
• Explain testing considerations.

Student Background and Knowledge

Before you attend this class, we recommend that you:

• Complete CBT 101: Introduction to SEL Relays OR have basic familiarity with protective relaying, SELogic control equations, front-panel controls, and the SEL-4000 Relay Test System.
• Have the ability to set up a communications session.