| 摘要 |
<p>1,134,906. Protective arrangements. BROWN, BOVERI & CO. Ltd. 21 Sept., 1967 [23 Sept., 1966], No. 43037/67. Heading H2H. Electrical apparatus comprising elements mounted on a withdrawable housing is so arranged that disconnection of the elements and withdrawal of the housing can be effected whatever the voltage condition of the apparatus. A thyristor 2 is connected to electrical bus-bars 4, 6 by means of a fuse 3 and a connector 5 respectively, the bus-bars 4, 6 being secured to a fixed part of the housing 1. The thyristor with its heavy current connections is contained in a withdrawable part of the housing and has a wall 9 at the front end thereof in which is an opening 22 and which carries a cover-plate 25 containing an opening 26. The openings 22, 26 are in axial alignment with sleeves 19 in which are captive screws 17 by means of which the thyristor 2 is connected to the bus-bars 4, 6. The control gear for the thyristor is contained in a chamber 10 at the front of the housing 1 and connected to a cable channel 13 by means of a plug and socket device 12. A displaceable wall 15 is secured in front of the wall 9 by means of a screw 24 to a bracket 30, the wall having openings 23, 27 therein. Thus when it is required to remove the withdrawable part of the housing access to the screws 17 can only be gained by first removing the plug from the plug and socket connection 12 thereby disabling the thyristor 2. After removal of the plug the screw 24 can be loosened whereby the wall 15 can be displaced to bring the openings 23, 22 and 27, 26 into alignment thus allowing the insertion of an insulated tool into the sleeves 19 whereupon the screws 17 can be removed to break the heavy current connections between the thyristor 2 and the bus-bars 4, 6. The housing 1 and the wall 15 may be of insulating material.</p> |
