PLASTICS-INSULATED SWITCH UNIT FOR MULTI-PHASE HIGH-VOLTAGE SWITCHGEAR INSTALLATIONS

摘要

A plastics-insulated switch unit for multi-phase high-voltage switchgear installations includes a frame made from a plastic material such as moulded synthetic resin in a solid or foam state providing parallel spaced cylindrical recesses for the respective phases for receiving plug-in type cylindrical switching modules which are ganged together for common operation. The recesses are provided with longitudinally spaced internal ring-shaped contact pieces which cooperate with external ring-shaped counter contact pieces provided on the switching modules and one of the ring-shaped contact pieces in each recess is earthed so as to provide an automatic earthing connection for all of the switching modules when in the withdrawn position.