Formula to Find Amp
Here is the formula for finding amps when horsepower is known.
Horsepower x 746/Volts x Efficiency x Power-Factor
Sometimes the tag or name plate on the motor will have the efficiency and power rating rating (both expressed in percentage).
.75hp x 746 = 559.5
120volts x 90% x 80% = 86.4
559.5/86.4 = 6.475 amps
I'm guessing at the Efficiency and Power-Factor. Your motor probably draws 5 - 7 amps.
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