Laboratory studies of the effects of multipulse lightning currents on distribution surge arresters

Multiple stroke lightning ground flashes can impose surges of exceptional severity on the arresters used to protect exposed distribution system equipment. The effects of representative multiple impulse currents on surge arresters are considered, and it is demonstrated that sextuple 8/20 mu s currents can cause damage to arrester blocks not evident with standard lightning current tests. Some speculation is offered about the relevance of these results to arrester testing techniques.<>