APP 311L: SEL-311L Line Current Differential Relay

Course Length: 2 Days (PDHs: 15)
Course Based Fees: $1,000*
* Plus Applicable Tax


APP 311L provides comprehensive application training for the SEL-311L Line Current Differential Relay, which offers complete line current differential protection with full scheme distance backup. In groups of two, students gain hands-on experience in communicating, metering, monitoring, commissioning, analyzing event reports, and performing control functions by working directly with the SEL-311L Relay.


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


Day 1

  • Applying Line Current Differential Protection With the SEL-311L
  • SEL-311L Line Current Differential Settings
  • SEL-311L Current Differential Channel Monitoring and Settings
  • Differential Protection Relay Word Elements
  • SELOGIC Control Equations: Ways to Implement and Document Relay Control Schemes
  • SEL-311L Relay Communications
  • Using acSELerator QuickSet SEL-5030 Software With the SEL-311L Relay
  • SEL-311L Trip Logic and Communications-Assisted Tripping Schemes
  • SEL-311L Relay Setting Example: Two-Terminal Line

Day 2

  • Metering and Monitoring Functions
  • SEL-311L Line Current Differential Relay Simplifies Commissioning Tests
  • SEL-311L Hands-On Training
  • Event Reporting
  • Frequently Asked Questions
  • SEL-311L Relay Backup Protection
  • SEL Mirrored Bits Communications

Learning Outcomes

At the conclusion of this course, students can:

  • Calculate and apply settings for line current differential protection.
  • Set the SEL-311L Relay using QuickSet.
  • Use SELogic control equations to customize the relay logic.
  • Apply backup protection, reclosing, and synchronism-check features of the SEL-311L Relay.
  • Analyze Sequential Events Recorder (SER) reports.
  • Implement relay-to-relay logic communications via the Mirrored Bits communications protocol.

Student Background and Knowledge

Before you attend this class, we recommend that you:

  • Have basic familiarity with protective relaying, SELogic control equations, QuickSet, front-panel controls, and the SEL-4000 Relay Test System.
  • Complete CBT 101: Introduction to SEL Relays.

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.

Available Courses

Request onsite training for your company.