Feeder Sizing for Multiple Motors
Feeder conductor (NEC 430.24) and feeder overcurrent device (NEC 430.62) for several motors on one feeder, with the largest-motor term shown.
Formula and source
Feeder conductor (NEC 430.24) >= 1.25 * FLC_largest + sum(FLC_other) + non-motor load. Feeder OCPD (NEC 430.62) <= largest_branch_device + sum(FLC_other), not rounded up (next standard size down where the sum is not a standard rating).
Feeder conductor and feeder overcurrent sizing for several motors on one feeder per NEC 430.24 and 430.62, by name; table FLC (not nameplate FLA) per 430.6(A). The AHJ-adopted NEC edition governs.
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