Fan Brake Horsepower
Air horsepower, brake horsepower, and the next standard NEMA motor size from airflow, total static pressure, and fan/drive efficiencies.
Formula and source
AHP = CFM * TSP / 6356; BHP = AHP / eta_fan; motor HP = BHP / eta_drive, rounded up to the next standard NEMA MG 1 size.
AMCA / ASHRAE fan-power relation BHP = (CFM * SP) / (6356 * eta) (public); standard motor HP sizes per NEMA MG 1, by name.
Audience
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