JP2020508557A5 - - Google Patents

Description

In addition, fuses are used in so-called shunt arms as backup protection for surge arresters. Here, a suitable fuse must guarantee protection in the event of a short circuit.

The fuses according to the invention are specifically intended for use in shunt arms in combination with surge protectors. The possibility of active operation of the short circuit auxiliary path is achieved by destroying the insulating element, especially the insulating foil, i.e. by using an exothermic reaction.

No additional external switching device is required as the insulating elements used, especially the insulating foil, meet the electrical requirements required for the insulating path for use in the shunt arm.

The fuse is used in the shunt arm, i.e. because there is no continuous current load, the fuse or cutting device is designed in such a way that the rated current of the fuse can be significantly reduced despite the same pulse current capacity. As a result, the scope of protection has already been significantly expanded.

This switching device meets the dielectric strength requirements for use in shunt arms. The dielectric strength corresponds at least to the protection level of the protected arrester in normal operation.

Claims (10)

It is composed of at least one soluble conductor located between the two contacts and arranged in the fuse housing, and a short-circuit auxiliary contact having an internal insulation distance from the soluble conductor, and can be connected to the supply network. A safety fuse for low voltage applications for surge protectors
An externally operable switching device to overcome the insulation distance causes a low impedance or a short circuit containing impedance between the auxiliary contact and the soluble conductor in the fuse housing. The switching device is formed and has an insulating element that forms the insulation distance and is subject to state changes to the external activator, the activator is connected to at least one control connection, and the safety fuse is A safety fuse, characterized in that it is connected to the surge protection device and is located on a shunt arm. The safety fuse according to claim 1, wherein the insulating element is designed as an insulating foil. The safety fuse according to claim 1 or 2, wherein the exothermic activator is formed as a reaction foil connected to an ignition device. The safety fuse according to claim 1 or 2, wherein the heat generating activator includes an electric bridge line igniter that directly or indirectly destroys the insulating element. The safety fuse according to claim 4, wherein the electric bridge line igniter drives a conductive element so as to overcome the insulation distance. The ignition device has an ignition element (A; B) that heats when an electric current flows, and the ignition element (A; B) is connected to the control connection (8). The safety fuse according to claim 3. A plurality of soluble conductors (1) are formed in parallel with each other in the fuse housing (6), and the plurality of soluble conductors (1) are guided by a disk supported in the fuse housing (6). The safety fuse according to any one of claims 1 to 6, wherein the switching device is arranged on the disk (13) or is arranged on the disk (13). The soluble conductor (1) has a portion in which the region is reduced and / or the cross section is reduced in each length range, and the switching device is made smaller on the surface and / or the cross section side. The safety fuse according to any one of claims 1 to 7, wherein the safety fuse is located in a portion not provided. In the case of a substantially cylindrical housing (6) having a cap-shaped contact (9) on the end face, the short-circuit auxiliary contact (3) exceeds one of the cap-shaped contacts (9). The safety fuse according to any one of claims 1 to 8, wherein the safety fuse is guided. The safety fuse according to claim 9 , wherein the at least one control connection (8) is guided through one of the cap-shaped contacts (9).