Adequate spacing prevents short circuits and enhances system safety: Bare copper busbars: Minimum clearance ≥20mm to avoid phase-to-phase or phase-to-ground faults. Insulated busbars: Insulation allows for reduced clearance but must meet IEC 60664or UL 746Cdielectric strength requirements. It defines the minimum distances between live parts and between live parts and earthed metal parts. The IEC 61439. Figure 1: High-performance VIOX industrial low voltage switchgear assembly, demonstrating modern compartment design, reliable circuit protection, and clear busbar phase identification for superior substation safety. What Does IEC 61439 Require for Low Voltage Switchgear Design? IEC 61439. Behind every reliable low voltage switchgear lineup is a design balance that is harder than it first appears: current must flow safely, heat must be controlled, internal space must stay usable, and the assembly must still be practical to manufacture, install, and maintain. It also depends on material choice, joint quality.
[PDF Version]