Answer / raju

p=v.i.cos phi

for 3 phase
p=root 3 v.i.cos pji

Answer / indri priyono

For calculate the electrical load and office can use basic formula P = V.I. cos phi --------------> single phase
P = 3.V.I. cos phi-------------> three phase

Where :
P = Power (Watt)
V = Voltage (Volt)
I = Current (Ampere)
Cos phi = usually range value between 0 ~ 1

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