... at 303-397 -22 95. ``,,,,,``,````,``,,,,`,```,``-`-`,,`,,`,`,,` PUBLISHED DOCUMENTPD IEC TR 60071- 4 :20 04 Insulation co- ordination —Part 4: Computational guide to insulation co- ordination ... normal distribution, ) 2 exp()( 2 βMXE ×= and 1)exp() 2 exp()( 2 2−×= ββMXσ E(X) is the mean value and σ(X) is the standard deviation. PD IEC TR 60071 4 :20 0439Copyright British Standards ... GEN1 GEN 2 Substation A Substation B ReactorReactor 33 kV 22 0 kV IEC 8 12/ 04 Figure D.1 – The line and the reactance are energized at the same time PD IEC TR 60071 4 :20 0499Copyright...