Motor Shaft Torque, Horsepower, and Speed

The horsepower-speed-torque triangle T = 5252 x HP / RPM, solving either way.

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Details, formula, and sources

Supply horsepower to get shaft torque, or torque to get horsepower, for coupling, belt, gearbox, and VFD torque-limit selection. The nameplate and driven load govern the service-factor margin.

T = 5252 x HP / RPM (5252 = 33,000 ft-lb/min per HP divided by 2 pi, the rev/min-to-rad/s bridge); inverse HP = T x RPM / 5252. Supply exactly one of HP or torque; the tile solves for the other.

First-principles rotational-power identity (power = torque x angular speed).

First-principles physics; no licensed source required.

Estimate. AHJ and licensed professional govern.

Field names used by the API: rpm, hp, torque_lbft

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