If you were on site and the MainSwitchboard was approximately 15 metres from a 1000 k VA 230/400 volttransformer with 5 percent impedance, how would you be able to determine theapproximate prospective short circuit current at the line side of the main switchon that switchboard?

You might consider doing your own schoolwork and tell us your conclusion so we can assist you. You learn nothing if ẃe tell you the answer.