Ohm Law:

        U=Volts, I=Amperes, R=Resistance, P=Power (expressed in watts)

U = I x R     P = I x U     I = U / R
R = U / I      I = P / U      U = P / I

Power - AC Systems:

	POWER FACTOR = Watts /(Volts x Amperes)
	  

	THREE PHASE KILOWATTS = (Volts x Amperes x Power Factor x 1.732) / 1000
	  

	THREE PHASE VOLT AMPERES =  Volts x Amperes x 1.732
	

                THREE PHASE AMPERES = (746 x Horsepower) / 1.732 x Volts x Efficiency x Power Factor
 

	SINGLE PHASE KILOWATTS = (Volts x Amperes) / 1000
	  

	SINGLE PHASE AMPERES = (746 x Horsepower) / (Volts x Efficiency x Power Factor)
	

Power - DC Systems:

	WATTS = Volts x Amperes
	  

	AMPERES = Watts / Volts
	  

	HORSEPOWER = (Volts x Amperes x Efficiency) / 746

Motor Application Formulas:
	

	TORQUE (lb-ft) =  (Horsepower x 5250) / RPM
	  

	SHAFT STRESS (Pounds Per Square Inch) = (HP x 321,000) / (RPM x Shaft Diam.)
	

Speed:

	SYNCHRONOUS RPM =  (Hertz x 120) / Poles
	  

	PERCENT SLIP =  ((Synchronous RPM - Full Load RPM) x 100) / Synchronous RPM
	

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