How to connect the small busbar after the K28A high-voltage switchgear is separated

Reconnect the small busbar by carefully aligning, cleaning, and bolting or clamping it to the switchgear terminals, ensuring proper conductivity and compliance with safety standards.

Preparation and Safety

Before reconnecting the busbar, ensure the switchgear is completely de-energized and properly grounded. Inspect the busbar and switchgear terminals for physical damage, corrosion, or oxidation. For copper busbars, polish the contact surfaces with fine sandpaper until smooth, and apply a power compound grease to enhance conductivity. For aluminum busbars, use an aluminum-specific anti-oxidation agent and, if connecting to copper, employ copper-aluminum transition joints with insulating heat-shrink tubing rated ≥125°C .

Connection Methods

Several methods can be used to reconnect the busbar:

• Bolted Connections: Align the busbar with the switchgear terminals and secure using stainless steel bolts and nuts. Ensure bolts match the connection holes and are tightened to the manufacturer's torque specifications .
• Clamps or Fixtures: Use mechanical clamps to hold the busbar in place, providing a strong and reliable connection while allowing for future maintenance .
• Compression Connectors: Apply pressure connectors for high-current applications to ensure a secure, low-resistance path .
• Plug-and-Socket or Crimped Lugs: For modular or removable connections, use plug-and-socket connectors or crimped lugs with insulating sleeves to maintain safety and ease of maintenance .

Alignment and Verification

Ensure the busbar is properly aligned with the switchgear contacts to avoid mechanical stress or misalignment. After connection:

1. Perform a mechanical check to verify tightness and alignment.
2. Conduct an insulation resistance test on the busbar and connected components.
3. Measure contact resistance by injecting a test current (e.g., 100A DC) to confirm uniform conductivity across all phases .

Operational Considerations

• Confirm the phasing of the busbar matches the switchgear configuration.
• Ensure all interlocks and safety mechanisms are operational.
• If the switchgear is part of a double-bus or bypass configuration, verify that the busbar reconnection does not compromise sectionalizing or maintenance flexibility . By following these steps, the small busbar can be safely and reliably reconnected after the K28A high-voltage switchgear has been separated, ensuring stable operation and compliance with electrical standards.