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SEL-421/SEL-421-1 Relay
Date Code 20020501
Table of Contents
Section 5: Front-Panel Operations
Front-Panel Layout ...................................................................................................................................... U.5.2
Front-Panel Menus and Screens .................................................................................................................. U.5.9
Front-Panel Automatic Messages .............................................................................................................. U.5.28
Operation and Target LEDs .......................................................................................................................U.5.30
Front-Panel Operator Control Pushbuttons................................................................................................ U.5.34
Section 6: Testing and Troubleshooting
Testing Philosophy....................................................................................................................................... U.6.2
Testing Features and Tools........................................................................................................................... U.6.5
Relay Test Connections................................................................................................................................ U.6.9
Test Methods.............................................................................................................................................. U.6.14
Checking Relay Operation......................................................................................................................... U.6.24
Relay Self-Tests ......................................................................................................................................... U.6.37
Relay Troubleshooting............................................................................................................................... U.6.40
Factory Assistance ..................................................................................................................................... U.6.43
Application’s Handbook
Section 1: Protection Application Examples
Section 2: Monitoring and Metering
Section 4: Time-Synchronized Measurements
Summary of Contents for SEL-421
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