HV Substation Commissioning Services
Our commissioning service verifies that all primary plant and associated secondary systems are installed in accordance with approved design documentation, electrically and mechanically sound, functionally coordinated, protection-aligned and correctly configured, and safe to energise and operate within network parameters. We verify a full range of equipment including power transformers, HV and MV circuit breakers, HV cables, protection, control and SCADA systems, current and voltage transformers, gas-insulated switchgear (GIS), and auxiliary and earthing transformers. Our commissioning capability covers voltage levels from 33kV to 330kV, with readiness to support 500kV transmission infrastructure.
EPEC's Commissioning Capability & Assurance
The EPEC Group HV Substation Commissioning Team ensures personnel and asset safety, compliance with applicable standards including AS/NZS 3000, AS 2067, IEC 60076 and IEC 62271-100, protection scheme integrity, system stability and operational readiness, and documented verification for regulatory and network requirements. Commissioning high-voltage infrastructure requires specialist personnel capable of managing energisation risk across both primary equipment and secondary protection systems. EPEC’s structured methodology ensures that all systems operate cohesively before assets are handed over for live operation.
Why it Matters
High-voltage assets operate under significant electrical and mechanical stress, and inadequate commissioning can result in catastrophic equipment failure, protection maloperation, extended outages, safety incidents, and network instability. A disciplined commissioning methodology reduces these risks by identifying installation defects, configuration errors, and integration issues before assets are placed into service.
EPEC provides complete commissioning services across transmission, distribution and renewable infrastructure projects, including:
- Solar Farms
- Industrial Power Systems
- Battery Energy Storage Systems (BESS)
- Brownfield upgrades & extensions
- Greenfield Substations
- Wind Farms
Our team bridges construction and operation by delivering:
- Pre-commissioning inspections and readiness verification
- Primary plant testing and diagnostics
- Secondary injection and protection validation
- SCADA and communications integration
- End-to-end scheme testing
- Controlled energisation support
- Post-energisation monitoring and fault analysis
Our Commissioning Capabilities
Power Transformer Testing, Commissioning & Maintenance
Comprehensive testing and commissioning of power transformers including insulation resistance, dielectric dissipation factor (DDF), winding resistance, turns ratio, and oil analysis. EPEC verifies transformer performance against design specifications and applicable standards (IEC 60076) prior to energisation.
- Insulation resistance and dielectric dissipation factor testing
- Winding resistance and turns ratio verification
- Oil sampling, dissolved gas analysis and moisture assessment
- Tap changer operation and timing tests
- Thermal imaging and on-load performance monitoring
CT Testing, Commissioning & Maintenance
Current transformer testing to verify ratio accuracy, polarity, magnetisation characteristics and insulation integrity. EPEC ensures CTs are correctly configured and coordinated with protection and metering systems before energisation.
- Ratio, polarity and phase verification
- Magnetisation curve testing
- Insulation resistance and primary injection testing
- Burden and accuracy class confirmation
- Integration testing with protection relays and metering
IVT & CVT Testing, Commissioning & Maintenance
Inductive and capacitive voltage transformer testing to confirm ratio accuracy, burden capacity, and transient response. EPEC validates voltage transformer performance to ensure reliable protection operation and accurate metering.
- Ratio and polarity verification
- Capacitance and dissipation factor testing
- Insulation resistance measurement
- Secondary injection and burden testing
- Integration with protection and SCADA systems
Earthing & Auxiliary Transformer Testing, Commissioning & Maintenance
Testing and commissioning of earthing transformers, neutral earthing resistors, and auxiliary power transformers. EPEC verifies correct grounding system operation and auxiliary supply integrity to support safe substation operation.
- Earth fault current path verification
- Neutral earthing resistor testing
- Auxiliary transformer ratio and insulation testing
- Step and touch potential assessment
- Earth grid continuity and resistance measurement
Vacuum/SF6 1/3 Pole HV Circuit Breaker Testing, Commissioning & Maintenance
Circuit breaker testing covering timing, contact resistance, insulation integrity, and SF6 gas quality. EPEC ensures breakers operate within manufacturer specifications and are correctly coordinated with protection schemes.
- Circuit breaker timing and travel analysis
- Contact resistance (micro-ohm) testing
- Insulation resistance and dielectric testing
- SF6 gas quality and leak rate assessment
- Trip and close coil operation verification
- Minimum trip voltage testing
Vacuum/GIS Switchgear Testing, Commissioning & Maintenance
Commissioning of gas-insulated switchgear (GIS) and vacuum switchgear assemblies, including partial discharge testing, gas quality analysis, and functional verification of all switching devices and interlocks.
- Partial discharge measurement and monitoring
- SF6 gas pressure and purity testing
- Mechanical and electrical interlock verification
- Primary and secondary injection testing
- Insulation resistance and high-voltage withstand testing
HV Cable Testing, Commissioning & Maintenance
High voltage cable testing including insulation diagnostics, sheath integrity testing, and cable termination verification. EPEC validates cable systems from installation through to energisation readiness.
- VLF (Very Low Frequency) and DC withstand testing
- Partial discharge measurement
- Cable sheath and jacket integrity testing
- Termination and joint inspection and testing
- Cross-bonding and earthing verification
Protection Relay Settings Configuration, Logic Design, Commissioning & Maintenance
Protection relay configuration, logic design, and secondary injection testing to verify correct operation under fault conditions. EPEC ensures protection schemes are coordinated, settings are aligned with approved studies, and relay logic operates as designed.
- Relay settings calculation and configuration
- Protection logic design and implementation
- Secondary injection testing of all protection elements
- Trip circuit supervision and breaker fail verification
- Protection coordination review against approved settings
Power Quality Meter Testing & Commissioning
Installation, configuration and verification of power quality meters to ensure accurate measurement of harmonic emissions, voltage fluctuations, and compliance with NSP connection requirements.
- Meter installation and configuration to NSP specifications
- CT/VT circuit verification for metering accuracy
- Communications and data logging validation
- Compliance testing against AS/NZS 61000 standards
- Integration with SCADA and remote monitoring systems
End-to-End Line Differential Protection & Integration with NSPs
End-to-end testing of line differential protection schemes, including communications channel testing and coordination with Network Service Providers. EPEC manages the interface between generator protection and NSP systems to ensure seamless fault detection and clearance.
- Differential relay configuration and testing
- Communications channel delay and performance verification
- Primary injection end-to-end testing
- NSP coordination and joint testing programs
- Stability testing under load and through-fault conditions
Bus-Zone Balance & Integration Testing
Busbar protection commissioning including CT circuit verification, balance testing, and stability checks to ensure correct zone discrimination and reliable fault clearance across all busbar configurations.
- CT circuit polarity and ratio verification for all feeders
- Busbar protection balance and bias testing
- Zone discrimination and stability testing
- Check zone and backup protection verification
- Primary injection testing across all circuit combinations
Power Transformer Testing, Commissioning & Maintenance
Comprehensive testing and commissioning of power transformers including insulation resistance, dielectric dissipation factor (DDF), winding resistance, turns ratio, and oil analysis. EPEC verifies transformer performance against design specifications and applicable standards (IEC 60076) prior to energisation.
Key capabilities:
- Insulation resistance and dielectric dissipation factor testing
- Winding resistance and turns ratio verification
- Oil sampling, dissolved gas analysis and moisture assessment
- Tap changer operation and timing tests
- Thermal imaging and on-load performance monitoring
CT Testing, Commissioning & Maintenance
Current transformer testing to verify ratio accuracy, polarity, magnetisation characteristics and insulation integrity. EPEC ensures CTs are correctly configured and coordinated with protection and metering systems before energisation.
Key capabilities:
- Ratio, polarity and phase verification
- Magnetisation curve testing
- Insulation resistance and primary injection testing
- Burden and accuracy class confirmation
- Integration testing with protection relays and metering
IVT & CVT Testing, Commissioning & Maintenance
Inductive and capacitive voltage transformer testing to confirm ratio accuracy, burden capacity, and transient response. EPEC validates voltage transformer performance to ensure reliable protection operation and accurate metering.
Key capabilities:
- Ratio and polarity verification
- Capacitance and dissipation factor testing
- Insulation resistance measurement
- Secondary injection and burden testing
- Integration with protection and SCADA systems
Earthing & Auxiliary Transformer Testing, Commissioning & Maintenance
Testing and commissioning of earthing transformers, neutral earthing resistors, and auxiliary power transformers. EPEC verifies correct grounding system operation and auxiliary supply integrity to support safe substation operation.
Key capabilities:
- Earth fault current path verification
- Neutral earthing resistor testing
- Auxiliary transformer ratio and insulation testing
- Step and touch potential assessment
- Earth grid continuity and resistance measurement
Vacuum/SF6 1/3 Pole HV Circuit Breaker Testing, Commissioning & Maintenance
Circuit breaker testing covering timing, contact resistance, insulation integrity, and SF6 gas quality. EPEC ensures breakers operate within manufacturer specifications and are correctly coordinated with protection schemes.
Key capabilities:
- Circuit breaker timing and travel analysis
- Contact resistance (micro-ohm) testing
- Insulation resistance and dielectric testing
- SF6 gas quality and leak rate assessment
- Trip and close coil operation verification
- Minimum trip voltage testing
Vacuum/GIS Switchgear Testing, Commissioning & Maintenance
Commissioning of gas-insulated switchgear (GIS) and vacuum switchgear assemblies, including partial discharge testing, gas quality analysis, and functional verification of all switching devices and interlocks.
Key capabilities:
- Partial discharge measurement and monitoring
- SF6 gas pressure and purity testing
- Mechanical and electrical interlock verification
- Primary and secondary injection testing
- Insulation resistance and high-voltage withstand testing
HV Cable Testing, Commissioning & Maintenance
High voltage cable testing including insulation diagnostics, sheath integrity testing, and cable termination verification. EPEC validates cable systems from installation through to energisation readiness.
Key capabilities:
- VLF (Very Low Frequency) and DC withstand testing
- Partial discharge measurement
- Cable sheath and jacket integrity testing
- Termination and joint inspection and testing
- Cross-bonding and earthing verification
Protection Relay Settings Configuration, Logic Design, Commissioning & Maintenance
Protection relay configuration, logic design, and secondary injection testing to verify correct operation under fault conditions. EPEC ensures protection schemes are coordinated, settings are aligned with approved studies, and relay logic operates as designed.
Key capabilities:
- Relay settings calculation and configuration
- Protection logic design and implementation
- Secondary injection testing of all protection elements
- Trip circuit supervision and breaker fail verification
- Protection coordination review against approved settings
Power Quality Meter Testing & Commissioning
Installation, configuration and verification of power quality meters to ensure accurate measurement of harmonic emissions, voltage fluctuations, and compliance with NSP connection requirements.
Key capabilities:
- Meter installation and configuration to NSP specifications
- CT/VT circuit verification for metering accuracy
- Communications and data logging validation
- Compliance testing against AS/NZS 61000 standards
- Integration with SCADA and remote monitoring systems
End-to-End Line Differential Protection & Integration with NSPs
End-to-end testing of line differential protection schemes, including communications channel testing and coordination with Network Service Providers. EPEC manages the interface between generator protection and NSP systems to ensure seamless fault detection and clearance.
Key capabilities:
- Differential relay configuration and testing
- Communications channel delay and performance verification
- Primary injection end-to-end testing
- NSP coordination and joint testing programs
- Stability testing under load and through-fault conditions
Bus-Zone Balance & Integration Testing
Busbar protection commissioning including CT circuit verification, balance testing, and stability checks to ensure correct zone discrimination and reliable fault clearance across all busbar configurations.
Key capabilities:
- CT circuit polarity and ratio verification for all feeders
- Busbar protection balance and bias testing
- Zone discrimination and stability testing
- Check zone and backup protection verification
- Primary injection testing across all circuit combinations
Commissioning Delivery Process
Pre-commissioning inspections and readiness verification
What we deliver
Visual defect identification and rectification tracking
Drawing verification and red-line markup documentation
Equipment labelling and site safety assessments
Primary plant testing and diagnostics
What we deliver
Insulation resistance and dielectric dissipation factor (DDF) testing
Contact resistance and circuit breaker timing tests
Current and voltage transformer ratio, polarity and magnetisation testing
Secondary injection and protection validation
What we deliver
Secondary injection testing of protection relays
Logic testing of control circuits and interlocks
Verification of protection settings against approved design coordination
SCADA and communications integration
What we deliver
Point-to-point signal verification from field devices to local HMI and remote control centres
IEC 61850 GOOSE messaging and DNP3 protocol testing
Fibre optic and communications network performance validation
End-to-end scheme testing
What we deliver
Primary injection to verify overall CT/VT circuits and protection stability
Busbar and transformer differential stability testing
Trip testing to confirm circuit breaker operation under fault conditions
Controlled energisation support
What we deliver
Development and execution of step-by-step energisation switching programs
Phasing and synchronisation checks across the network boundary
Live monitoring of system parameters during initial voltage application
Post-energisation monitoring and fault analysis
What we deliver
On-load measurements to confirm CT/VT secondary currents and voltages
Thermal imaging and partial discharge assessments
Compilation of final commissioning reports and compliance documentation
Pre-Commissioning Inspections & Readiness Verification
- Visual defect identification and rectification tracking
- Drawing verification and red-line markup documentation
- Equipment labelling and site safety assessments
Primary Plant Testing & Diagnostics
- Insulation resistance and dielectric dissipation factor (DDF) testing
- Contact resistance and circuit breaker timing tests
- Current and voltage transformer ratio, polarity and magnetisation testing
Secondary Injection & Protection Validation
- Secondary injection testing of protection relays
- Logic testing of control circuits and interlocks
- Verification of protection settings against approved design coordination
SCADA & Communications Integration
- Point-to-point signal verification from field devices to local HMI and remote control centres
- IEC 61850 GOOSE messaging and DNP3 protocol testing
- Fibre optic and communications network performance validation
End-to-End Scheme Testing
- Primary injection to verify overall CT/VT circuits and protection stability
- Busbar and transformer differential stability testing
- Trip testing to confirm circuit breaker operation under fault conditions
Controlled Energisation Support
- Development and execution of step-by-step energisation switching programs
- Phasing and synchronisation checks across the network boundary
- Live monitoring of system parameters during initial voltage application
Post-Energisation Monitoring & Fault Analysis
- On-load measurements to confirm CT/VT secondary currents and voltages
- Thermal imaging and partial discharge assessments
- Compilation of final commissioning reports and compliance documentation
