Short Circuit Current Calculator — Free Online Calculator
Estimate available short circuit (fault) current at a panel based on transformer size and impedance.
How to Use This Calculator
Enter transformer kVA, impedance percentage (from nameplate), secondary voltage, and phase.
The Formula Explained
Available fault current at transformer secondary: Isc = FLA / %Z. FLA = kVA × 1000 / (V × √3 for 3-phase). This is the maximum theoretical fault current, actual will be lower due to cable impedance.