Question { 5981 }

i am working in automation feild my question is that how to find the KVA of transformer.

Answer

thats a silly question yar
we know power=v*i for single phase
power=3vi where v&i are line parameters

Question { 6350 }

What are the possible causes if load is not same on all the
three phases

Answer

if load is unbalanced i.e load currents are unbalanced due
to this unbalanced currents the total current at neutral
point will not equal to zero

Question { 8203 }

why dc supply given to ac alternator rotor

Answer

the dynamical induced emf needs a constant flux i.e time
invarient flux
if we give the ac input it produces alternating flux in the
rotar field and then there is no emf is induced so the
electrical power will be zero

Question { IBM, 5792 }

what is auto transformer

Answer

it is working on the self induction principle but where as
normal t\f works on the principle of mutual induction.it has
only one winding