Spacings between Busbars: The spacings between busbars are critical to prevent electrical shock and ensure safe operation. ANSI switchgear standards are generally performance standards. Dielectric tests, power frequency withstand for all voltages and impulse. enclosure, or exposed metal part. " And for general industrial control equipment, voltage range 301-600, shortest distance is shown as 1/2" with this same value being shown through. The metal-enclosed non-segregated phase bus runs are designed for 635 V, 5 kV, 15 kV, 27 kV and 38 kV service in accordance with ANSI C37. Available ratings are shown in Table 11. Main keywords for this article are Bus Bars and Bus Ducts Design Requirements, ANSI C37.