Spacings between Busbars: The spacings between busbars are critical to prevent electrical shock and ensure safe operation. If you can place bare conductors 1/2" apart and meet the test requirements for 15kV equipment, that is fine. And before you conclude that I'm being ridiculous, remember that we do this every day in vacuum interrupters. The first is. In pollution degree 3, designers must use bigger phase-to-phase and phase-to-earth spacing, or use additional insulation barriers. These are practical values, often higher than the IEC minimums, and depend. And for general industrial control equipment, voltage range 301-600, shortest distance is shown as 1/2" with this same value being shown through oil or air over surface. Between live parts of opposite polarity, 251-600V, Through air gap is 1", Over surface is 2". Double spacer for easy leveling and connecting on both sides (snubber.
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