Parallel arrangement: Uniform spacing minimizes EMIand skin effect losses, ensuring balanced current distribution. Support insulator spacing: Typically 300mm–500mmto withstand mechanical stress from short-circuit forces. Those who ask are frequently surprised by the answer: None. Dielectric tests, power frequency withstand for all voltages and impulse. The closest distance I have between the bus bars and the panel itself is 0. This dimension is the one that concerns me and has ultimately led me to posting here. A calculation program is available for this purpose which, in addition to the parameters already mentioned, takes into account the following factors for the material: Flexural rigidity of the material. The distances. 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. Compact. Unipolar busbar supports Multipolar busbar supports I ccup to 80 kA I ccup to 80 kA Flat mounting 100 A 400 A 500 A 630 A 1000 A 1600 A 2500 A 4000 A 5800 A 7 000 A Hexagonal insulators Nominal current In Unipolar busbar supports I ccup to 50 kA Other supports Edgewise mounting SB C 10SB C 10 SB C. The NEC requires a minimum spacing of 12 inches (305 mm) between busbars, but this can be reduced based on the busbar current and configuration.