Short Circuit Current Formula ^new^ -

In a "perfect" short circuit, the load resistance becomes zero, meaning the current is only limited by the impedance of the transformer, cables, and the power source itself. Calculating Short Circuit Current in Transformers

[ I_SC = \fracFLA%Z_transformer ]

if you provide the KVA and Voltage.

For three-phase short circuits in systems with a higher fault level: short circuit current formula

That’s a massive surge from a modest transformer. In a "perfect" short circuit, the load resistance