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In a 3 – phase motor, the voltage and current measured are as given below. L1 : 230 V, 5 A L2: 230 V, 4.5 A L3: 230 V, 5.5 A What’s the input power, assuming power factor of 1?

In a 3 – phase motor, the voltage and current measured are as given below. L1 : 230 V, 5 A L2: 230 V, 4.5 A L3: 230 V, 5.5 A What’s the input power, assuming power factor of 1? Correct Answer 3,450 Watt

Concept:

Input power of 3 phase motor = 3 VP IP cos ϕ

Where,

VP = phase voltage

IP = phase current

cos ϕ = power factor

For different phase rating,

Input power of 3 phase motor = Vp1 Ip1 cos ϕ + Vp2 Ip2 cos ϕ + Vp3 Ip3 cos ϕ

Calculation:

Input power of 3 phase motor = (230 X 5 X 1) + (230 X 4.5 X 1) + (230 X 5.5 X 1)    

Input power of 3 phase motor = 3,450 Watt

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