Repeat Example 13.8 for a \(115-\mathrm{kV}\) system with a 1.08 per-unit maximum \(60-\mathrm{Hz}\) voltage under normal operating conditions and with a \(450-\mathrm{kV}\) BIL.

Data From Example 13.8:-

Table 13.2:-

Consider the selection of a station-class metal-oxide surge arrester for a 345-kV system in which the maximum 60-Hz voltage under normal system conditions is 1.04 per unit. (a) Select a station-class arrester from Table 13.2 with a maxi- mum continuous operating voltage (MCOV) rating that exceeds the 1.04 per- unit maximum 60-Hz voltage of the system under normal system conditions. (b) For the selected arrester, determine the protective margin for equipment in the system with a 1300-kV BIL, based on a 10-kA impulse current wave crest- ing in 0.5 s.