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SEL-421
Overview
Documentation
Specifications
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SEL-421
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Overview
Documentation
Specifications
Support
Documentation
Featured
Instruction Manual
SEL-421-4, -5 Protection, Automation, and Control System and SEL-400 Series Relays
Data Sheet
SEL-421-4, -5 Protection and Automation System
Flyer
SEL-421 Protection, Automation, and Control System
Literature
Documents sorted by newest first.
Include English Literature
Literature
Flyers
Featured
SEL-421 Protection, Automation, and Control System
SEL Digital Secondary System Solutions
SEL Time-Domain Link (TiDL) Technology
Data Sheets
SEL-421-4, -5 Protection and Automation System
SEL-421-7 Protection, Automation, and Control System With Sampled Values or TiDL Technology
Guideform Specifications
SEL-421-7 Relay with Sampled Values or TiDL Technology
SEL-421-7 Relay with Sampled Values or TiDL Technology
SEL-421-4, -5 Protection, Automation, and Control System
SEL-421-4, -5 Protection, Automation, and Control System
Installation Guides
SEL-400 Series TiDL Quick-Start Guide
Installing IP52 Dust Protection for SEL-400 Series Panel-Mount Relays
Instruction Manuals
SEL-421-4, -5 Protection, Automation, and Control System
SEL-421-4, -5 Protection, Automation, and Control System and SEL-400 Series Relays
SEL-421-7 Protection, Automation, and Control System With Sampled Values or TiDL Technology and SEL-400 Series Relays
SEL-421-7 Protection, Automation, and Control System With Sampled Values or TiDL Technology
Configurable Labels
SEL-400 Series Configurable Label Template (Vertical)
SEL-400 Series Configurable Label Template (Vertical; A4)
SEL-400 Series Enhanced HMI Configurable Label Template (Horizontal)
SEL-400 Series Enhanced HMI Configurable Label Template (Horizontal; A4)
SEL-400 Series Configurable Label Template (Horizontal)
SEL-400 Series Configurable Label Template (Horizontal; A4)
SEL-400 Series Enhanced HMI Configurable Label Template (Vertical)
SEL-400 Series Enhanced HMI Configurable Label Template (Vertical; A4)
SEL 400 Series Configurable Label Instructions
Related Downloads
SEL-421-4, -5 DNP3 Device Profile Information
SEL-421-7 DNP3 Device Profile Information
Certificates
SEL-421-4,5 IEC 61850 Edition 2 Conformance Certificate
SEL-421-7 IEC 61850 Edition 2 Conformance Certificate
SEL-421-4,5 IEC 61850 Edition 2 MICS
SEL-421-4,5 IEC 61850 Edition 2 PICS
SEL-421-4,5 IEC 61850 Edition 2 PIXIT
SEL-421-4,5 IEC 61850 Edition 2 TICS
SEL-421-7 IEC 61850 Edition 2 MICS
SEL-421-7 IEC 61850 Edition 2 PICS
SEL-421-7 IEC 61850 Edition 2 PIXIT
SEL-421-7 IEC 61850 Edition 2 TICS
Publications
Application Guides
Programming Non-Directional Distance Elements in the SEL-411L and SEL-421
Related Material
AG2023-10
Applying SEL Relays in Systems With Inverter-Based Resources
Healthy Voltage Supervision for Manual Alternate Voltage (ALTV) Activation in SEL-400 Line Relays
Maintaining Switched-Mode Relay Responsiveness in an RSTP Network
Implementation of the SEL-49 Relay Line Thermal Protection in the SEL-421 Relays Using
SELogic
Equations
Basic Configuration of Sampled Values Using SEL-401 Merging Unit and SEL-421-7 SV Subscriber Relay
Testing Power Elements in the SEL-351S, SEL-421, and SEL-700G
Related Material
Testing Power Elements
Testing the Conventional Out-of-Step Element Using Multistate Tests for Line Protection Relays
Related Material
OOS Testing
Applying SEL-411L and SEL-421 Relays to Permissive Underreaching Transfer Trip (PUTT) Schemes
Defining DCE and DTE: Null Modem Cable and Straight-Through Cable Applications
Implementing Inverse-Time Frequency Elements Using SEL-400 Series Relays to Comply With NERC Standard PRC-024-3
Use SEL-300 and SEL-400 Series Relays to Set Up POTT and DCB Schemes
Understanding and Effectively Using the SEL
Mirrored Bits
Protocol
Testing the High-Speed Mho Elements in the SEL-411L and SEL-421
Related Material
High-Speed Mho Distance Testing
Maintaining IEC 61850 Configuration While Upgrading Firmware in SEL-400 Series Relays
Mapping Analog Inputs to a SCADA Protocol for Remote Indication of Fault Location in SEL-311, SEL-321, SEL-421, and SEL-411L Relays
Revised Setting Guidelines for E32 in SEL Relays
Circuit Breaker Monitoring Using the SEL-421 Relay
Testing the SEL-421-4-5 Quadrilateral Phase Element for a Balanced Three-Phase Fault
Related Material
Quadrilateral Phase Testing Calculator Spreadsheet
Using the SEL-421 to Functionally Replace the SEL-68
Related Material
acSELerator
QuickSet SEL-5030 Software example file(1)
Implementing Memory Register Functions Using Advanced
SELogic
Control Equation Math Functions in SEL-400 Series Relays
Applying the SEL-421 Relay to Permissive Overreaching Transfer Trip Schemes
Setting the SEL-421 Relay With Sub-Cycle Elements in a Directional Comparison Blocking Scheme
Reclosing in the SEL-421 for Different Reclose Supervision Conditions
Implementation of Inverse-Time Over- and Undervoltage Elements in SEL-451 and SEL-421 Relays
Applying the SEL-421 Protection, Automation, and Control System Recloser on Adjacent Lines With Breaker-and-a-Half Bus Arrangement
Recommended Ways to Detect Loss-of-Potential (LOP) Conditions in the SEL-321, SEL-421, and SEL-311 Series Relays
Setting an SEL-421-1 Relay to Obtain SEL-287V-0 Relay Functions
Related Material
Setting Mask Conversion 287V0 to 421-1 (.xls)
SEL-287V0 to SEL-421-1 Application Example (.rdb)
Using SEL-421 Relay Synchrophasors in Basic Applications
LOG Input Considerations When Implementing a DCUB Scheme Using
Mirrored Bits
Communications in the SEL-321, SEL-311C, SEL-311L, and SEL-421 Relays
SEL-421 Relay Fast Messages
Programming a LOCK Pushbutton in the SEL-421 Relay
Use SEL-421, SEL-321, and SEL-311 Relays Where Different Systems Are Required for Primary and Backup Line Protection
Application Notes
Changing Metering Direction in SEL-400 Series Relays for SCADA Applications
Archive Wide-Area Information With Synchrophasors
Detecting Power System Islanding With Time Error Measurement
Estimating Power System Frequency With Synchronized Measurement
Generator Black-Start Restoration Using Synchronized Measurement
Technical Papers
Challenges and Solutions for Distance Elements Protecting Transmission Lines With Tapped Loads
Complete Monitoring Solution to Improve Reliability and Performance of Digital Secondary Systems
Distance Element Polarizing Logic for Systems With Low Inertia
Power-Swing Detection Logic for Systems With Low Inertia
Catastrophic Breaker Failures Due to Missing Current Zero-Crossings in Highly Shunt-Compensated 500 kV Lines—Point-on-Wave, Reclosing, and Protection Considerations
Improving Ground Fault Sensitivity for Transmission Lines Near Inverter-Based Resources
Getting the Lines Crossed—How a Three-Phase Series Fault Caused a Sequence of Relay Operations
Security Criterion for Distance Zone 1 Applications in High SIR Systems With CCVTs
Evaluating Phasor-Based and Time-Domain Elements for Short Line Applications
Applying Dependable and Secure Protection With Quadrilateral Distance Elements
Ground Fault Protection for Resistance-Grounded Collector Feeders With Inverter-Based Resources
Performance of IEC 61850 Sampled Values Relays for a Real-World Fault
Attack Tree Analysis of a Digital Secondary System in an Electrical Substation
Improve Protection Communications Network Reliability Through Software-Defined Process Bus
Voltage and Current Inversion Challenges When Protecting Series-Compensated Lines – A Case Study
Zero-Setting Power-Swing Blocking Protection
Line Protection: Redundancy, Reliability, and Affordability
Experience With Subcycle Operating Time Distance Elements in Transmission Line Digital Relays
Transmission Line Protection System for Increasing Power System Requirements
Application Guidelines for Power Swing Detection on Transmission Systems
Relay-to-Relay Digital Logic Communication for Line Protection, Monitoring, and Control
White Papers
Best Practices for Implementing PTP in the Power Industry
Fly Safe and Level: Customer Examples in Implementing Dual Primary Protection Systems
SEL-421 Performance As Both a Protective Relay and a Phasor Measurement Unit
Drawings
PDF
SEL-421 Front- and Rear-Panel Diagrams