HIGH-VOLTAGE CURRENT-LIMITING CUTOUT Russian patent published in 1998 - IPC

FIELD: electrical engineering, cutouts with high switching-off capability. SUBSTANCE: high-voltage current-limiting cutout has insulation case 1 filled with quartz sand closed by caps 2 on ends inside which fuse link 3 is placed. Fuse link presents core 4 with spiral wound on it and with at least one fuse element 5 made of round wire. Fuse element 5 comprises repeating identical sections 6 incorporating two parts: First one 7 which section smoothly grows in axial direction from minimal to maximal value followed by subsequent smooth decrease to minimal value. Relation of perimeter of fuse element to its section smoothly changes in axial direction from maximal value in minimal section to minimal value in maximal section. Second part 8 has minimal section. Ratio of maximal value of section to minimal value amounts to 1.3:1.5. Relation of entire length of section 6 to length of its part 8 with minimal section is 5:10 depending of diameter of wire. EFFECT: improved functional efficiency and reliability. 2 dwg