Partial discharge Partial discharge In electrical engineering, partial discharge (PD) is a localized dielectric breakdown (DB) of a small portion of a solid or fluid electrical insulation (EI) system under high voltage (HV) stress, which does not bridge the space between two conductors. While a corona discharge (CD) is usually revealed by a relatively steady glow or brush discharge (BD) in air, partial discharges within solid insulation system are not visible. PD can occur in a gaseous, liquid or solid insulating medium. It often starts within gas voids, such as voids in solid epoxy insulation or bubbles in transformer oil. Protracted partial
Halo (religious iconography) that clearly denotes a full-body halo that is not vesica piscis shaped. "Halo" by itself, according to recent dictionaries, means only a circle around the head, although Rhie and Thurman use the word also for circular full-body aureoles. Halo (religious iconography) A halo (from Greek , "halōs"; also known as a nimbus, aureole, glory, or gloriole) is a crown of light rays, circle or disk of light that surrounds a person in art. They have been used in the iconography of many religions to indicate holy or sacred figures, and have at various periods also been used in images of