A 3 phase motor operating off 415V system is developing 20Kw
at an efficiency of 0.77 and power factor of 0.73.
determine:-

a)the line current.
b)the phase current if winding are delta connected.
c)the phase voltage if winding are star connected.



A 3 phase motor operating off 415V system is developing 20Kw at an efficiency of 0.77 and power fac..

Answer / v.srinivas

I=P/1.732 X 415 X EFF X PF=49.5(LINE CURRENT)
28.57 AMPS (PHASE CURRENT)
Phase voltage in star connection; 718.78

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