In 3rd edition, single momentary flashover is not regarded as insulation breakdown during carrying out Hi-Pot test. How about multi-time flashovers?
During the test, breakdown constitutes a failure. Insulation breakdown is considered to have occurred when the current which flows as a result of the application of the test voltage rapidly increases in an uncontrolled manner, that is, the insulation does not restrict the flow of the current. Corona discharge or a single momentary flashover is not regarded as insulation breakdown.