Insulating or quenching gas monitor for power circuit breaker - has leakage detector near at least one switching pole which controls light beam from HV to earth, on leakage

摘要

The monitor is particularly intended for sulphur hexafluoride insulated outdoors power circuit breakers, with at least one switching pole at high voltage. Near one switching pole (24,26) is mounted a leakage detector (46) which controls, in case of leakage, a light beam transmitted from high voltage to earth. A photocell (38) is at the earth potential and transmits a signal on the light beam impingement. Pref. the light beam is transmitted from high voltage to earth by an optical fibre (32) of electrically insulating material. A light source (36) may be connected to the high voltage, which may be masked or exposed by a shutter segment actuated by the leakage detector. An insertion of a convex lens may be used for focussing the light source emission to the optical fibre input. Two optical fibres may be used when the light source is at earth potential, one fibre transmitting the light to a mirror system feeding the second fibre, leading to the photocell.