GB227350A - Improvements in and relating to electric switch gear for outdoor transformers and transmission lines - Google Patents

Abstract

227,350. Johnson, E. May 28, 1924. High potential switches ; switchboards.-The high and low tension switch fuses of an open-air transformer station carried by a pole, have. movable contacts in the form of replaceable fuses which are carried by a hoistable guided bar operated from the foot of the pole and so arranged that the contacts may be partially lowered for breaking the circuits or may be brought to the ground level for replacement of fuses. The high tension supply lines 180 are attached to the insulators 2 mounted on an upper cross bar secured between the poles 1 and are connected bv bars 17 to inserted sockert contacts 18. Immediately below are contacts 120 carried by insulators 2<1> and connected to the terminals of the transformer 3 mounted between the poles, the contacts 120 being connected by bars 20 to lower ring-shaped contacts 19. The movable bridging contacts consist of fuses 10 with metal end caps 11 secured on a hoistable cross-bar 13. The bar 13 is secured to a guiding plate 14 which can be hoisted along vertical guide rails 7 bv a rope 15 passing over a pulley 8, the rope being wound by a winch 16. Also mounted on the cross bar 13 are low-tension fuses 23 which act as bridging members to connect pairs of fixed contact members 22, the upper sets of which are connected bv leads 26 to the low-tension side of the transformer 3 and the lower set passing to low-tension power lines 4, 5. When the frame 13, 14 is raised the lower contacts 19 act as guides for the fuses 10, the high and low tension circuits being simultaneously completed. The frame may be partially lowered for breaking these circuits or completely lowered to ground level for renewal of the fuses. The construction of the low-tension fuses is shown in Fig. 3, the cartridge fuse, 24 being mounted within an insulating casing 25 secured to the bar 13. The lower fuse contact rests on a metal plate 40 connected to an external annular contact 31 the upper contact 30 being connected by a clip 29 to a metal end cap 28. These contacts cooperate with sets of fixed contacts 32, 33 when the bar 13 is raised.