Horizontal tubular busbars should be installed with proper support, alignment, and fittings to ensure safe, efficient, and mechanically stable power distribution.

Material Selection

Tubular busbars are typically made from aluminium for new installations or copper for extensions to existing systems. Aluminium is preferred for its lightweight and corrosion resistance, while copper is used where continuity with existing copper arrangements is required ( ). The choice of material affects current-carrying capacity, mechanical strength, and compatibility with fittings.

Support Structures and Insulators

Horizontal busbars must be mounted on support insulators and longitudinal stays to maintain alignment and prevent sagging. The spacing of supports is critical for mechanical stability and short-circuit strength. Standard busbar spacing is often 60 mm center-to-center, though 40 mm, 100 mm, and 185 mm systems are also used depending on design requirements ( ). Insulators should be rated for the system voltage and environmental conditions.

Fittings and Connections

All fittings, clamps, and connectors should be designed to avoid deformation of the tubular conductor. Fixed fittings typically require two complete clamps for mechanical stability, while sliding fittings use clamps according to current rating ( ). Special attention is needed for aluminium-to-copper connections to prevent electrochemical corrosion. Fittings must comply with relevant standards such as ENA TS 41-11 for aluminium and ENA TS 41-16 for copper.

Electrical Considerations

• Ensure the busbar cross-section meets the current-carrying requirements, taking into account continuous current, short-circuit currents, and temperature rise ( ).
• Centralized infeed and symmetrical load distribution along the busbar length improve efficiency and reduce hotspots.
• Proper insulation materials (e.g., epoxy-glass, heat-shrink tubing) can enhance safety, reduce inductance, and prevent accidental contact ( ).

Installation Best Practices

• Verify alignment and spacing before securing busbars to supports.
• Use torque-controlled tools for clamps to avoid over-tightening or deformation.
• Ensure all connections are clean and free from oxidation.
• Follow manufacturer guidelines for current rating, mechanical support, and environmental conditions.
• Conduct a final inspection to confirm mechanical stability, electrical continuity, and compliance with standards ( ).

Safety and Standards Compliance

Horizontal tubular busbar installations must comply with BS EN 61936-1 for high-voltage power installations and relevant national or international standards. Consider wind loading, short-circuit forces, and ambient temperature when designing support spacing and conductor size ( ). By following these guidelines, horizontal tubular busbars can be installed safely, ensuring reliable power distribution and long-term mechanical and electrical performance.