To Find

Direct Current

ALTERNATING CURRENT

Single-Phase

Two-Phase* Four Wire

Three-Phase

Amperes when Horse-power is known

H.P x 746

E x % EFF

H.P x 746

E x % EFF x P.F

H.P x 746

2 x E x % EFF x P.F

H.P x 746

1.73 x E x %EFF x P.F

Amperes when Kilowatts is known

K.W x 1000

E

K.W x 1000

E x P.F

K.W x 1000

2 x E x P.F

K.W x 1000

1.73 x E x P.F

Amperes when K.V.A is Known

K.V.A x 1000

E

K.V.A x 1000

2 x E

K.V.A x 1000

1.73 x E

Kilowatts

I x E

1000

I x E x P.F

1000

I x E x 2 x P.F

1000

I x E x 1.73 x P.F

1000

K.V.A

I x E

1000

I x E x 2

1000

I x E x 1.73

1000

Horse-power (output)

I x E x % EFF

746

I x E x % EFF x P.F

746

I x E x 2 x % EFF x P.F

746

I x E x 1.73 x % EFF x P.F

746

I = Amperes   ·   E = Volts   ·   % EFF = per cent efficiency   ·   P.F = Power Factor .8   ·   K.W = Kilowatts
K.V.A = Kilo-Volt-Amperes   ·   H.P = Horse Power
* For three wire, two phase circuits the current in the common conductor is
1.41 times that in either of he other two conductors.