Answer / wareagle

Vipul Kumar your answer is wrong.

W is not = 1.732x380xI. W =1.732x380xIx PF. You left off
the power factor



Bala your answer is wrong also.

KA is not equal power/ (1.732*400*% of Impedance)Note
spelling of impedance. Where did you go to school?



Amps = 30 KVA/ (0.380 x 1.73)or 30000 va/380 x 1.73

Amps = 46

Answer / wareagle

simon says

30Kva=30,000va

30,000 VA=440V*68.1818 Amp*1 (Pf)

Hense Ka=0.068 Wrong



Simon if you look at the post, the voltage is 380 volt and
not 440 volts as you posted. Also you incorrectly forgot to

use 1.73 when working with 3 phase voltage.

Answer / simon

30Kva=30,000va
30,000 VA=440V*68.1818 Amp*1 (Pf)
Hense Ka=0.068

Answer / vipul kumar rai

W=1.732x380xI
30x1000=1.732x380xI
I=30000/658.16
I=45.581 ( FOR THE PRIMARY CURRENT )
W=1.732x220xI
I=78.731 ( FOR THE SECONDRY CURRENT )

Answer / bala

we need to know the Impedance of the TxR.Becos the Formula for Determine the KA value is
=power/ (1.732*400*% of Impedence)
For EX-
Power = 1500 KVA
Voltage = 400V
Impedance = 6%
short circuit = 1500*1000/(1.732*400*0.06)
= 36085A or 36 KA

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