Dielectric strength of magnetic wire coatings exposed to simultaneous thermal and radiation aging

The Arrhenius equation is used as a basis for accelerated determination of electrical insulation life. The usefulness of exposing insulation to simultaneous thermal and radiation aging in order to further accelerate aging mechanisms has been evaluated. Five different enamel wire coatings falling into five different temperature classes, were selected as test specimens (MW 28, MW 30, MW 74, MW 35, and MW 16). The test specimens were divided into three groups. The first group was used to establish initial values of dielectric strengths of the specimens. The second group was exposed only to high temperature. The third group was exposed to both high temperature and radiation from a cobalt 60 source. The results obtained show that the combination of high temperature and radiation can help determine the thermal class quicker than thermal exposure alone