PK = VP IP cos ΦK

3 PK = 3 VP IP cos ΦK

OR

3 PK = 3 VP IP pf

VL = VP, and IL = √3 IP.

(P) = 3 VL IL pf √3

P = √3 V I pf

ExampleA three-phase 415 V motor draws 10 A at 0.8 power factor. How much power does it consume?

P = √3 V I λP = √3 x 415 x 10 x 0.8P = 1.732 x 415 x 10 x 0.8 = 5750.41 WP = 5.75 kW