Short-Circuit Calculator
⚠️
Reference values for preliminary design. Final protection settings must be verified by a qualified engineer per IEC 60909 / NEC 110.
⚙️ Transformer & System
Transformer capacity (kVA)
Impedance voltage Z (%)
4%
6%
5%
Secondary voltage (kV)
0.4
0.69
0.22
Recommended breaker rating
IEC
NEC
📊 Result
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Short-Circuit Calculator
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