I have a 4 MVA transformer with subtransient reactance of 8%. The SC MVMA will be 50 MVA and short circuit current delivered will be 2624 Amps and rated current will be 210 Amps.
Now, I have to select circuit breaker of 11 kV.
a) with 25 percentage margin also, the rated current: 400 Amps.
b) SC current of breaker will be 8 kAmps.
Is the above calculation correct?