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Phase Academy
ALL PATHSPATH · 04

Protection & Relay Coordination

From what a relay measures to why a coordinated curve set clears the closest device first, using time-current visualisation and differential scenarios.

LEVEL
Advanced
TOTAL TIME
2 h 25 min · 4 modules
AUDIENCE
Engineer, Technician
VERSION
v2.0 · Published
YOUR PROGRESS0 / 4 · 0%

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Module timeline

  1. Relay fundamentals

    Guided scenario 35 min

    Explain relay inputs, pickup, and time delay in terms of what the relay actually measures.

    Lab: Protection Zone & Relay Scheme ExplorerCompletes on: lab opened, guided scenario steps confirmed, knowledge check submitted, reflection confirmed
    Open module

  2. CT and PT measurement

    Guided scenario 30 min

    Describe instrument transformer ratio, burden, and saturation effects on protection.

    Lab: CT / PT and Relay Measurement SimulatorCompletes on: lab opened, guided scenario steps confirmed, knowledge check submitted, reflection confirmed
    Open module

  3. Time-current coordination

    Guided scenario 45 min

    Build a coordinated curve set and identify miscoordination.

    Lab: Protective Relay Coordination / TCC VisualizerCompletes on: prediction recorded, lab opened, guided scenario steps confirmed, knowledge check submitted, reflection confirmed
    Open module

  4. Differential protection

    Guided scenario 35 min

    Explain differential zones and why inputs must be matched in ratio and phase.

    Lab: Differential Protection SimulatorCompletes on: lab opened, guided scenario steps confirmed, knowledge check submitted, reflection confirmed
    Open module

What you will be able to do

  • Explain what a protective relay measures and how it decides to operate
  • Describe CT and PT behaviour, including saturation and burden
  • Read and build a coordinated time-current curve set
  • Explain differential protection zones and why they need matched inputs

Prerequisites

  • Power Systems Analysis, or equivalent fault-current experience

What counts as complete

All four modules marked complete with checks and reflections recorded.

Opening a lab never marks a module complete on its own.

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