Estimate a motor's full load amps from horsepower, voltage, efficiency, and power factor.
Full load amps (FLA) is the current a motor draws at its rated load. For a three-phase motor, FLA = (HP × 746) / (1.732 × V × efficiency × power factor). This calculator gives the calculated running current plus the 125% figure used for conductor and overload sizing.
The calculated value is great for quick checks, but for code compliance always use the motor nameplate current and the NEC 430.250 table. To control that motor, see whether a VFD or soft starter fits your application.
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