Transformer Impedance Short-Circuit Assessor

Calculate potential secondary short-circuit fault current ($I_{sc}$) based on transformer kVA and percent impedance ($\%Z$).

Short-Circuit Fault Equations: I_FLA = (kVA × 1000) / (1.732 × V_sec) | I_sc = I_FLA / (%Z / 100)

Transformer Parameters

System Phase Configuration

Transformer Rating (kVA)

Secondary Line Voltage ($V_{sec}$)

Percent Impedance ($\%Z$) Typical dry-type values: 2.0% to 5.75%

Full Load Current ($I_{FLA}$) 208.2 A

Max Fault Current ($I_{sc}$) 8,328 A

Recommended AIC Rating 10 kAIC

PRIMARY SIDE: Inrush Current Factor ~ 10x - 12x FLA

Transformer Rating: 75 kVA | Impedance: 2.5% Z

SECONDARY BUS FAULT POINT: Maximum Available Peak Short-Circuit = 8,328 Amps