IEC 60909-0:2016
International standard. c_max = 1.10 (LV + HV). Defines equivalent voltage source method, κ factor, m/n factors, K_T and K_G correction.
VDE 0102 (Germany)
German national implementation of IEC 60909-0. c_max = 1.05 for LV networks (≤ 1 kV), 4.5% lower maximum fault currents. Standard for switchgear selection in Germany and Austria.
BS 7639 (UK)
British standard for short-circuit calculation, harmonised with IEC 60909-0. Same c-factor table as IEC. Used alongside Engineering Recommendation G74 for UK distribution networks.
GB/T 15544 (China)
Chinese national standard harmonised with IEC 60909. Symmetrical component method, same c-factors. Required for grid fault level studies in China. Supplemented by DL/T 5222 for power system planning.
JIS C 4620 (Japan)
Japanese switchgear standard referencing IEC 60909 method for rated short-circuit withstand current. 50/60 Hz mixed grid. Used with IEC 62271-200 for LV/MV switchgear selection.
IS 13234 (India)
Indian standard for three-phase fault level calculation based on IEC 60909 method. 50 Hz grid. Used with IS 13118 for switchgear selection across HV/MV/LV levels.