# How to find Amp (Amperes) in ac and dc

E = Voltage
I = Amps
PF = Power Factor
Eff = Efficiency
HP = Horsepower

Formula for finding Amperes when Horsepower is known in direct current (dc) and alternative current (ac):

To Find (Formula)
Direct Current (DC) Alternating Current
Single Phase Two Phase / Four Wire Three Phase
Amperes when Horsepower is known
HP X 746
——————
E X EFF
HP X 746
——————
2 X E X EFF X PF
HP X 746
—————–
2 X E X EFF X PF
HP X 746
—————-
E X EFF X PF X 1.73

Formula for finding Amp when Kilowatts is known in direct current (dc) and alternative current (ac):

To Find (Formula)
Direct Current (DC) Alternating Current
Single Phase Two Phase / Four Wire Three Phase
Amperes when Kilowatts is known
KW X 1000
——————
E
KW X 1000
——————
E X PF
KW X 1000
—————–
2 X E X PF
KW X 1000
—————-
E X PF X 1.73

Formula for finding Amp when KVA is known in direct current (dc) and alternative current (ac):

To Find (Formula)
Direct Current (DC) Alternating Current
Single Phase Two Phase / Four Wire Three Phase
Amperes when KVA is known
KVA X 1000
——————
E
KVA X 1000
—————–
2 X E
KVA X 1000
—————-
E x 1.73

Formula for finding Kilowatts in direct current (dc) and alternative current (ac):

To Find (Formula)
Direct Current (DC) Alternating Current
Single Phase Two Phase / Four Wire Three Phase
Kilowatts
E X I
——————
1000
E X I X PF
——————
1000
I X E X 2 X PF
—————–
1000
E X I X 1.73 X PF
—————-
1000