Surge test levels for form wound stators
The question of surge test voltage levels used for testing the turns insulation of form wound stators comes up often. And, why wouldn’t it? Many service centers have several good coil suppliers in their qualified supplier lists and quite a few customers who own form wound motors. It’s not unlikely that each of the coil suppliers and each of the customers could be specifying different test levels. What’s more, most authoritative standards or guides available provide a range of test levels. This is because not all insulation systems are designed to have the same surge withstand capability. Also, the turn insulation properties of one particular system can vary widely depending on the extent of processing complete at the time of test.