Separating Device For A Surge Arrester And Arrangement

Abstract

A separating device for a surge arrester has a housing and a fuse is arranged in the housing. There is also described an arrangement that includes a surge arrester and a separating device as described.

Claims

1-16. (canceled)

17. A separating device for a surge arrester, the separating device comprising: a housing; and a fuse disposed in said housing.

18. The separating device according to claim 17, wherein said fuse, for the purpose of a tripping event, comprises an electrical conductor configured to melt as a result of a heating effect of a current flow, and also an insulating material which encloses said electrical conductor.

19. The separating device according to claim 17, wherein said housing at least partially comprises a glass fiber-reinforced plastic.

20. The separating device according to claim 17, further comprising an insulating sleeve with leakage path-extending shields arranged on said housing.

21. The separating device according to claim 20, wherein said insulating sleeve at least partially comprises silicone rubber.

22. The separating device according to claim 17, further comprising a first connecting device disposed at a first end of the separating device in order to connect the separating device to a suspension.

23. The separating device according to claim 22, further comprising a second connecting device disposed at a second end of the separating device in order to connect the separating device to a surge arrester.

24. The separating device according to claim 23, wherein said second connecting device is configured to form an angle of between 10 and 170 between the separating device and the surge arrester.

25. The separating device according to claim 24, wherein said second connecting device forms a substantially right angle between the separating device and the surge arrester.

26. The separating device according to claim 17, wherein said fuse is configured to break a current path before a maximum short-circuit current is reached.

27. The separating device according to claim 17, wherein said fuse is configured to break a current path when temporary surges of a predetermined voltage level and duration occur.

28. The separating device according to claim 17, further comprising an arc rotation apparatus.

29. The separating device according to claim 17, further comprising an indicator apparatus configured to indicate a tripping of the separating device.

30. An arrangement, comprising: a separating device according to claim 17; and a surge arrester connected to said separating device.

31. The arrangement according to claim 30, wherein said surge arrester is configured for medium voltage.

32. The arrangement according to claim 30, further comprising a suspension connecting said surge arrester to said separating device.

Description

[0035] For better explanation of the invention, in a schematic representation:

[0036] FIG. 1 shows a surge arrester having a separating device according to the invention, and

[0037] FIG. 2 shows a section of the separating device in the tripped state.

[0038] FIG. 1 shows a surge arrester 1 having a multiplicity of varistor disks 22 stacked on one another. These are fixed in a tube 23 between two end fittings. The surge arrester comprises a housing having shields 24, which extend the creepage path. The surge arrester furthermore comprises a first connecting bolt 25 and a second connecting bolt 20. The second connecting bolt 20 is provided with an external screw thread and is fed through an opening in a second connecting device 12. The surge arrester is fixed on the second connecting device 12 by means of a threaded nut 21, which is arranged on the second connecting bolt 20.

[0039] A first part, which is used for connecting the surge arrester, of the second connecting device 12 is denoted by the reference 28. A second part 29, which is used for connecting a separating device 1 according to the invention, is arranged at a right angle a to the aforementioned first part 28 of the second connecting device 12. The separating device 1 is configured as a GFRP tube 8. An insulating housing 9 made of silicone rubber, which like the surge arrester is provided with shields, is fitted on the tube 8. The tube 8 is closed on both sides by covers 4, 5. A fuse is arranged inside the separating device 1. For the event of tripping, the latter comprises an electrical conductor 6 which can be melted as a result of a heating effect of a current flow. In the example, the conductor 6 is configured as a thin wire made of silver. The conductor 6 is tensioned between two connecting terminals 10, 11. An insulating material 7, which encloses the conductor, is furthermore provided inside the housing 4, 5, 8 of the separating device 1. For example, the insulating material 7 is at least partially a sand, in particular quartz sand. If a fault event occurs, the conductor 6 melts because of the heating effect and an arc discharge is formed. The arc discharge is in this case formed, in particular, when the metal of the conductor is converted from the liquid state to the gaseous state. The insulating material 7 has the property of rapidly causing the arc discharge to quench, wherein a fusion zone which is formed vitreously is created in the case of a quartz sand. In this way, the electrical connection which previously existed through the conductor 6 is securely DC-isolated and is no longer electrically conductive.

[0040] In order to make a fault event visible, a local mechanical indicator apparatus 13, 14, 15 is provided. In the simplest case, this is a tube 14 which is fed through an opening in the part 29 onto the cover 5. A coil spring 13 is held under constraint inside the tube by being compressed by an indicator means 15. The indicator means 15 is connected under constraint to the conductor 6. A holding device 3 is connected to the cover 4 on the side of the separating device 1 facing away from the surge arrester. The holding device 3 connects the arrangement consisting of the surge arrester and the separating device 1 to a schematically indicated suspension 2, which is for example configured as an overhead line pylon.

[0041] One great advantage of the arrangement represented is that the separating device 1 with the fuse is simultaneously configured as an insulating bracket, or carrier arm or holding arm, for the surge arrester. This saves material and costs. Furthermore, the explosive charge-free configuration of the separating device entirely prevents the formation of sparks. The arrester represented with the separating device may therefore advantageously be used particularly in climatic regions with a risk of bush fires, for example Australia or California.

[0042] FIG. 2 shows a section of the separating device 1 in the tripped state. In this case, the conductor 6 is melted and a disconnection point 16 has been formed. By the tripping of the separating device 1, or by separation of the conductor 6, the coil spring 13 has been able to expand and push the indicator means 15 partially out from the tube 14. Ejection of the indicator means 15 from the tube 14 may, for example, be prevented by a suitable stop (not represented). The indicator means 15 may for example be configured with a signal color, for instance red, so that in the event of tripping it indicates in a way which is visible to maintenance engineers over a large distance that the separating device has tripped and the arrester, or the separating device, needs to be replaced.