Relay Testing

Protection Relay Testing & Commissioning Services

The protection relay system is the last line of defence against electrical faults that can destroy assets and endanger lives. Green Watt's relay testing service covers commissioning, periodic maintenance testing, and post-fault investigation of protection relays from simple overcurrent relays to complex numerical IEDs.

Service Scope

Commissioning Testing

  • ›Visual inspection of relay panel wiring against approved drawings
  • ›Secondary injection testing of each relay element with advanced relay test equipment
  • ›Verification of relay settings against protection coordination study
  • ›Binary input and output functional testing
  • ›CT and PT circuit continuity, polarity, and burden verification
  • ›End-to-end protection scheme testing (POTT, DUTT schemes)
  • ›Differential relay percentage-bias characteristic verification
  • ›Distance relay characteristic verification (Mho, Quadrilateral)

Periodic Maintenance Testing

  • ›Secondary injection at key points of each characteristic
  • ›Trip circuit integrity and trip coil resistance verification
  • ›Battery and DC supply voltage check
  • ›Relay flag, target, and indication check

IED (Intelligent Electronic Device) Testing

  • ›IEC 61850 GOOSE message functional testing using K68i relay test set
  • ›Setting file version verification and change management record
  • ›Disturbance record retrieval and analysis

Post-Fault Investigation

  • ›Relay event record and disturbance recorder data extraction and analysis
  • ›Assessment of relay operation (correct, overreach, underreach, non-operation)
  • ›Recommendations for setting revision

What You Receive

  • Relay test report with as-found and as-left settings for each relay
  • Protection coordination assessment notes
  • Commissioning certificate or maintenance record
  • Recommended actions for any out-of-tolerance relays

Why Choose Green Watt Field Services

✓Qualified electrical engineers with HV testing experience
✓Calibrated instruments traceable to national standards
✓Comprehensive written reports with photographs
✓Rapid mobilisation across India
✓Independent third-party assessment
✓Pan-India service coverage

Request a Service Proposal

Tell us about your site and requirements. We'll respond with a service scope and fee proposal within one working day.

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Coverage

Delhi NCR, Maharashtra, Karnataka, Tamil Nadu, Gujarat, Eastern India and all major industrial centres.