IEEE Recommended Practice for Thermal Cycle Testing of Form-Wound Stator Bars and Coils for Large Rotating Machines

This procedure is intended for form-wound bars/coils for rotating machines rated 10 kV or more at 50 Hz or 60 Hz that are subjected to many transitions from no-load to full-load current during normal operations, and where rapid load variations are typical. Only the thermal cyclic degradation within the groundwall insulation and/or the conductor package and delamination of the groundwall insulation from the conductor are addressed by this test. The procedure is applicable to indirectly-cooled machine types such as: -- combustion turbine generators -- pumped storage or peaking duty hydrogenerators -- synchronous condensers -- cyclic duty water pump motors Various pass/fail criteria are presented, and the ones that apply in a specific circumstance must be agreed between user and manufacturer prior to commencement of testing