Generator Sizing

Continuous and surge wattage from running totals and the largest motor's starting draw.

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Formula and source

Required kW = max(starting kVA / surge factor, sum of running loads / efficiency); largest-motor LRA contribution per NEC 430.251(B).

NEC 2023 (NFPA 70). Article 700 / 701 / 702; NEMA MG 1 by name.

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