Partial-discharge pulse-sensor for HV appts. - has different attenuation-frequency response according to whether one of two output connections is open- or short-circuited

摘要

The sensor (4) is based on an annular measurement electrode (5) surrounded by a metallic support ring (6) from which it is insulated electrically by four fixing elements (8). The ring incorporates axial holes (7) for screws securing it to the housing of the appts. The pulses are taken via pref. 50-ohm screened cables from two diametrically opposed output connections (16,17). The cable cores are in electrical contact with the sleeves of these connections, while the screens are earthed in additional holes through the ring. USE/ADVANTAGE - Esp. for metal clad gas-insulated switchgear, or h.v. electrical machine, e.g. transformer or generator for quality control during mfr. or prefabrication. Very efficient pulse extn. is associated with transmission properties characterised by high limit frequency and adaptable to different measurement purposes.