Electrical Formulas - Generac Power Systems XT-EFI Series Manual

Electrical Formulas

To Find
Kilowatts (kW)
KVA
Amperes
Watts
No. of Rotor Poles
Frequency
RPM
kW (required for Motor)
Resistance
Volts
Amperes
E = Volts
Term
Current
Wattage
Voltage
Resistance
E
I R
Known Values
Volts, Current, Power Factor
Volts, Current
kW, Volts, Power Factor
Volts, Amps, Power Factor
Frequency, RPM
RPM, No. of Rotor Poles
Frequency, No. of Rotor Poles
Motor Horsepower, Efficiency
Volts, Amperes
Ohm, Amperes
Ohms, Volts
I = Amperes
Symbol Measurement
I Amps
P Watts
E Volts
R Ohms
P
I E
1-phase
E X I
1000
E x I
1000
kW x 1000
E
Volts x Amps
2 x 60 x Frequency
RPM
RPM x Poles
2 x 60
2 x 60 x Frequency
Rotor Poles
HP x 0.746
Efficiency
E
I
I x R
E
R
R = Resistance (Ohms)
Constant
Voltage
E
Voltage
E
Resistance
R
Resistance
R
Current
I
003003
Current
I
Power
P
Power
P
Power
P
Power
P
3-phase
E x I x 1.73 x PF
1000
E x I x 1.73
1000
kW x 1000
E x 1.73 x PF
E x I x 1.73 x PF
2 x 60 x Frequency
RPM
RPM x Poles
2 x 60
2 x 60 x Frequency
Rotor Poles
HP x 0.746
Efficiency
I x R
PF = Power Factor
Shift Result
Resistance Current

Increase Decrease
Resistance Current

Decrease Increase
Voltage Current

Decrease Decrease
Voltage Current

Increase Increase
Resistance Voltage

Decrease Decrease
Resistance Voltage

Increase Increase
Voltage Power

Increase Increase
Voltage Power

Decrease Decrease
Current Power

Increase Increase
Current Power

Decrease Decrease
E
I
E
R









