IEC 60865-1:2016
If you're interested in accessing the PDF, I recommend checking the official IEC website or other reputable sources that provide access to international standards. iec 60865-1 pdf
This part of the IEC 60865 series provides a method for calculating short-circuit currents in three-phase a.c. systems. The standard is applicable to electrical power systems operating at a frequency of 50 Hz or 60 Hz, with a maximum voltage of 230 kV (RMS). IEC 60865-1:2016 If you're interested in accessing the
Short-circuit currents - Part 1: Calculation of short-circuit currents in three-phase a.c. systems iec 60865-1 pdf