Commissioning HV and LV equipment involves systematic inspection, installation, testing, and verification to ensure safe, reliable, and standards-compliant operation.

Pre-Installation and Inspection

Before installation, all equipment must be unboxed and inspected to confirm it matches specifications and has not been damaged during transit. For HV switchgear, verify rated voltage and short-circuit breaking current, while LV switchgear requires checking rated current and outgoing circuits. Foundation and floor leveling must be confirmed to prevent misalignment, and cabinets should be positioned according to approved drawings, with deviations kept minimal (≤5mm) for precise operation .

Installation and Mechanical Assembly

• Cabinet Handling: Use forklifts with protective padding for heavy cabinets (>400kg) and maintain tilt angles ≤15° to avoid internal damage .
• Positioning and Fastening: Number cabinets sequentially (incoming → metering → outgoing) and mark floor positions. Secure cabinets with proper leveling and torque specifications for all connections .
• Busbars, Bushings, and Control Cables: Install busbars, bushings, and top-mounted boxes where applicable. Connect control and interconnection cables, ensuring proper earthing and grounding .

Electrical Pre-Commissioning Tests

Pre-commissioning ensures the equipment is ready for energization:

• Insulation Resistance Testing: Verify insulation integrity of all HV and LV components .
• Contact Resistance Testing: Check all switchgear contacts for proper conductivity and mechanical operation .
• Continuity and Earthing Checks: Confirm all protective grounding and bonding connections are correct .
• Functional Verification: Test auxiliary systems, protection relays, and control circuits to ensure correct operation .

Site Acceptance Testing (SAT)

After installation, SAT tests validate the system under operational conditions:

• Energize equipment sequentially, starting with LV panels, then HV switchgear.
• Verify protection relay settings, interlocks, and communication systems.
• Conduct load tests and simulate fault conditions to confirm correct tripping and safety mechanisms .
• Document all test results for future reference and maintenance planning .

Final Commissioning and Handover

• Ensure all equipment is fully operational, safe, and compliant with local standards (e.g., EN 62271 for Europe, ANSI for the Americas), .
• Provide training for operational staff and hand over documentation, including test reports, wiring diagrams, and maintenance manuals .
• Decommission and safely remove any old equipment if part of a replacement project .

Key Considerations

• Follow international and local standards for HV/LV equipment.
• Maintain strict safety protocols during handling, testing, and energization.
• Document every step to ensure traceability and facilitate future maintenance . By adhering to these procedures, commissioning ensures reliable, safe, and efficient operation of high and low voltage complete sets of equipment, minimizing downtime and operational risks.