Abstract :
In an effort to clarify the confusion that has existed during past years regarding the flashover strength of insulators, the A.I.E.E. lightning and insulator subcommittee∗ has been engaged, jointly with high voltage laboratories of several insulator manufacturers, in an investigation to determine and eliminate differences in insulator flashover data from different sources, and to obtain reliable flashover data for standard insulators and gaps. In this latest report, the subcommittee presents average 60-cycle and impulse flashover voltages for suspension insulator strings consisting of 10-in. units with 5 3/4;-in. spacing, and for coördinating gaps with various spacings.