Answer / viswakumar

% impedance is the voltage required to circulte full load
current in both HV and LV windings when the terminals of
the LV winding is shorted. This is just the SC test done
in the college lab.

For example if 5 % of 11KV circultes full load current in
the both 11KV side and 415 V side of a 11KV/415 volt
transformer then the % impedance of the transformer is 5%

Answer / abdulsubur

1000kva trasformer

1000/root3*.4=1445A=I flow in secondary current

400*5.75%=23

23/1400=.2 0hms

Answer / abdulsubur

impedence of trasformer = rated kva\root 3 *secondary
voltage

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