What's inside
1
IEC 61936-1:2021 indoor clearances (phase-phase, phase-earth) 1–36kV
IEC 61936-1:2021 §5.3
2
IEEE 80 Sverak Rg formula with typical worked value
IEEE 80:2013 §14.3 Eq. 52
3
Transformer impedance defaults by MVA class (IEC 60076-5)
IEC 60076-5:2006 §4
4
IEEE 80 surface layer Cs derating table (ρs, hs combinations)
IEEE 80:2013 Eq. 27
Related calculators
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