Matl - WG1776 - Materials SC - Thermal Evaluation of Insulation Systems

A test procedure (Combination of IEEE Stds. 275-1992 ™ & 429-1994 ™) for comparing two or more insulation systems in accordance with their expected life at rated temperature is outlined. The procedure is limited to insulation systems for alternating-current (ac) electrical machines using form-wound pre-insulated stator coils rated 15000 V and below. There was a lot of discussion about the inadequacy of the sketch of the formette frame, so I had new sketches for low and high voltage coils made by Siemens Energy & Automation. There was also considerable discussion about the differences between ‘stub’ and ‘U’ connections, but we decided not to change the sketch of the ‘simulated’ connections used on formettes. Definitions were added per present IEEE requirements. Photographs of formettes and a bibliography were also added as Annexes.