The duration of the test is- 1 h for accessories having a rated current not exceeding 32 A;- 2h for accessories having a rated current exceeding 32 A but not exceeding 125 A;- 3h for accessories having a rated current exceeding 125 A but not exceeding 250 A.For accessories having a rated current exceeding 250 A, the test shall continue until thermal stabilization is attained. Thermal stabilization is considered to have occurred when three successive readings, taken at intervals of not less than 10 min, show no further increases of more than 1 K.