DE102007042989A1 - Short-circuiting device for surge arresters - Google Patents

Abstract

The invention relates to a short-circuiting device for surge arresters such as varistors, spark gaps or the like, comprising a movable conductive or conductive sections having short-circuiter, which is held under mechanical prestressing, by a fixing device, wherein the fixing device releases when heating the short-circuiter, so that this the surge arrester connection contacts bridges or connects. According to the fixation device is arranged at a point with determined strongest warming in case of overload directly on or on the surge and configured over a minimized heat capacity, neither the short-circuiter nor the fixing parts of the normally energized in the event of operation elements of the surge arrester.

Description

The The invention relates to a short-circuiting device for surge arresters such as varistors, spark gaps or the like, comprising one movable conductive or conductive sections having short circuiter, which under mechanical Preload is held by a fixing device, wherein the fixing device when heating the short-circuiter free so that it bridges the surge arrester connection contacts or connects, according to the preamble of the claim 1.

According to the state of the art, simple disconnecting devices are used for monitoring varistors as surge arresters, the z. B. have a standing under mechanical bias switching tongue, which exerts a switching movement by thermal separation of a solder joint and thus interrupts the current path. Such thermal separation devices, which can also be combined with a predetermined breaking point for high currents, are for example in the DE 42 41 311 A1 or the DE 38 05 889 A1 explained.

alternative surge arresters can be disconnected if overloads occur also be shorted. Both separation and shorting serve to protect the surge arrester from overloading. For low voltage applications, the separation is dominant. The advantage of this known protection method is that at the most frequent overload cases the separating device disconnects the varistor from the mains, whereby the mains supply exists remains.

In some cases of overload, in which a high fault current is to be interrupted by the separating device or the supply voltage is greatly increased, the switching capacity of the separating device can be exceeded. The resulting arc between the switching tongue and the fixed terminal of a varistor can not be deleted. The resulting long-lasting energy input into the surge arrester can lead to burnup of the connecting parts and ultimately to the destruction of the arrester, but also to consequential damage in the system to be protected. In such cases, the realization of a short circuit of the arrester is advantageous because the upstream overcurrent protection devices have a much higher switching capacity. With regard to the realization of short-circuiting devices for varistors z. B. on the DE 33 18 588 A1 . DE 37 34 214 A1 or the DE 26 34 479 directed.

From the US 4,068,281 or the EP 0 860 927 A1 Protective devices are already known, which activate a short-circuit path via an electronic evaluation of the load.

In the DE 33 18 588 A1 a varistor with short-circuit capability is disclosed. When the varistor is heated, a spring-loaded connection leg is moved directly or after deformation of an insulation part against a short-circuit contact. The disadvantage here is that the temperature-sensitive material is either directly integrated in the circuit and thus is cooled by the metallic leads or that is dissipated via the feed line heat between the varistor and the temperature-sensitive material. This significantly increases the delay time between reaching the critical temperature on the varistor and the response of the temperature sensitive materials. With a very rapid heating of the varistor this can not be sufficiently protected against overloading and destruction.

The DE 26 34 479 A1 shows a varistor with a spring-biased shorting bar. There, although the spring clip is not integrated directly into the supply path, but its direct contact with the temperature-sensitive material leads to a relevant cooling thereof, which also results in this solution of the prior art, a significant delay time. In addition, the above-described solution has a considerable space requirement and it is the short-circuit current carrying capacity limited.

According to DE 37 34 214 A1 a thermal separation device is known which can realize a short circuit in a parallel path via an executed changeover contact. In this separation device, the separation of the varistor via a Lotstelle in the supply path. The heat dissipation and thus the delay time are very high.

A thermally sensitive separation point of a conventional separation device, as shown in the 1 , which represents the state of the art in the most general way, can be used in principle for a short-circuiting. The soldering point here connects two metal parts, which have a high heat conduction and a high heat capacity, since these metal parts forcibly have to control all current loads in the work area of the arrester. The solder joint itself must meet the requirements of the pulse current carrying capacity. In addition, the solder joint is permanently exposed to the mechanical stress of the spring bias acting on the moving part of the feeder. An optimization to the actual function, namely the separation of the varistor during its heating is not possible according to the prior art. Thermal separators of the known type have a considerable inertia, which is based in particular on the thermal conductivity of the materials used, the necessary connection cross-sections and the resulting large heat capacity.

In case of overload, So especially when the heating of the varistor due of prolonged overvoltages or aging of the Varistors is the Lotstelle the separating device due to explained conditions only gradually heated. That means, even after reaching one one more time passes for the varistor critical temperature for a long time, until the soldering point the necessary melting temperature reached. Often this causes an overload of the varistor before thermal separation can occur. An overload of the varistor can also be undefined with respect to the resulting fault current and thus to a variety of different further errors and damage.

As already mentioned, solutions are part of the stand the technique in which a separation of the thermally sensitive part from the main current path. In the previously known solutions could However, the problem of large heat capacity or the strong cooling of the thermally sensitive part can not be eliminated, which in particular at a fast Heating of the varistor does not provide adequate protection could be. The protection devices developed for this reason, among others based on electronic or electromechanical systems Also aim at improved protection of the varistors in fast Heating processes, but are very expensive, costly and prone to failure.

Out The above, it is therefore an object of the invention, a further developed Short-circuiting device for surge arresters, as Varistors, spark gaps or the like means to indicate whose The principle of action consists in the triggered state one Short circuit path in a parallel path to the faulty arrester too turn off, leaving the original current as a short-circuit current commuted into the parallel path. The short-circuiting device to be created should have the shortest possible delay, so that an unwanted destruction of the surge arrester can be avoided or the damage due to arcing limited is. The solution to be created should also be simple, save space and be cost effective.

Furthermore the short-circuiting device should also be combined with be known per se known separation devices.

The Solution of the object of the invention is achieved by a short-circuiting device for surge arresters according to the Feature combination according to claim 1, wherein the dependent claims at least expedient refinements and developments represent.

It it was recognized that surge arresters, z. Varistors, due to the installation situation, the material structure, the geometry and the contacting of the pads and the power distribution Have areas of different heating. Therefore is the point or according to the given circumstances the area of the strongest warming for the positioning of the thermally sensitive part, d. H. the fixing device, select.

The thermally sensitive part is also about have the lowest possible heat capacity and have a low heat dissipation. In one embodiment The invention is a movable contact piece of the supply line applied to the surge arrester with a spring preload. The connection of this movable contact piece with the surge arrester via a Contact point. Cheap for the execution Such a contact point is when the direction of the surge current load occurring current forces does not act against the contact force.

at This embodiment of the invention is merely one further continuous current contact with corresponding Provide counterpotential. This contact is arranged so that between the various potentials a sufficient separation distance is present and that the moving section, which at the further contact is moved, a sufficient continuous current carrying capacity has.

On the area of the varistor with the strongest warming a thermally sensitive part is attached as a fixing device. This fixing device should have a low heat capacity feature. For connecting to the surge arrester Waxes, adhesives, solders or suitable materials are included a melting point or a softening temperature just above the usual operating temperature of the surge arrester at. These materials then either communicate directly or in conjunction with intermediate pieces the actual moving part of the Shunt devices.

If necessary for design reasons, the temperature-sensitive Fixing device not be attached directly to the varistor. In In this case, however, care must be taken to ensure that the Heat conduction between the strongest point expected warming and fixation sufficient is, namely at a per se to be minimized heat capacity.

Then, when the melting temperature of the temperature-sensitive area or the fixing device is reached, the shorting bar moves to the additional contact with the consequence of the desired rapid short-circuiting of the relevant surge arrester.

at a further embodiment of the invention, the short circuit also on two separate opposite polarity contacts by movement of a corresponding Contact piece to be realized towards these contacts.

at very steep and high surges or surge currents, in which the surge arrester, in particular a Varistor, overloaded within a few microseconds is, finds almost no before the destruction of the varistor Warming instead. In these cases, it is suggested the short-circuiting device according to the invention, d. H. the fixing device, in an area of an additional housing to arrange the surge arrester, this area in the case of an emerging arc, temperature and / or gas effects of the arc collects or bundles. This means, the resulting hot gas, which is present in case of damage, is directly to the fixer and provided there thermally directed at sensitive area. This can be realized in the simplest case be that the surge arrester down to the area the contacting of the temperature-sensitive material completely is enclosed. This can be the hot gas or plasma be led to a chimney-like channel, in which a wire or a thread of the fixing is located. When Temperatursensibel here is the contact point of the triggering device with the varistor and in the case of a thread made of insulating material also considered the material of the thread, which in the case of the arc effect Melt or extend.

at a wrapped version of the surge arrester In addition, the pressure development for be used the short circuit. For this purpose, the pressure acts, z. In Shape of a piston system, directly contact the short circuit. The mechanical strength of the holding system (contact point, strength of the wire) is already overloaded at low pressures.

The Short-circuiting device of the invention is about a thermal separation point with the actual monitored Element, d. H. a varistor or a spark gap connected and z. When exceeding a certain amount of heat z. B. soldered or by changing the viscosity triggered an adhesive. As a result, in one Parallel path to the affected element a shorted path closed, without the actual overvoltage protection element separated becomes. Since the parallel path in each case lower impedance than the defective Arrester is, there is an almost complete commutation of the current over the thus created bypass, whereby the Power conversion in the defective arrester element to a negligible lower Value is reducible. What is essential is that the current commutation already done before z. B. a varistor due to its degree of destruction is alloyed. This requires a fast switching device, the invention by a lossless heat transfer from the surge arrester to the thermal separation point and from there to the actual short-circuit switch marked is.

As already explained, there is a direct thermal contact the fixing device or the thermal separation point with the surge arrester or Protective element, in particular a varistor or a spark gap. The thermal separation point is the actual switching device thermally decoupled, the short-circuiting in the Normal state is potential-free. In one embodiment is an potential-free short-circuit contact with high short-circuit and continuous current load through Heat dissipation from the contact point before.

at a further embodiment of the invention is the Short-circuiting device of a device in which a wire applied directly to a varistor over a Spring force is biased. At the opposite end the wire has a preferably circular contact plate on the one hand with its underside the spring in the untried State spans and the other in the triggered state with its top creates a short-circuit connection between two contact bars. These contact bars are in turn with the respective connection potentials of the varistor and so with the external terminals connected so that the contact plate the connection of the bypass and thus triggers the intended current commutation.

there the contact plate preferably consists of a mechanical and thermal highly resilient insulation material, eg. B. of glass fiber reinforced epoxy resin. At the outer edge area is a circular metallic coating available. This metallic coating or a metallic shorting ring soldered to it in the tripped state interposes the intended short-circuit connection the aforementioned contact ironing ago.

By the design of the contact plate takes place in the state "thermal Disconnect the heat dissipation exclusively the wire with a small diameter, but due to its low thermal conductivity and the existing low mass is negligible.

The wire can also be made by a plastic be replaced, which melts in place of the Lotstelle under heat through the varistor and thus releases the bias of the contact plate on the spring force.

If the contact plate the aforementioned circular, or circular ring ring-shaped contact having over an insulating line on the contact plate of the optionally potential-carrying wire separated and thus both thermally and Also electrically isolated from this leads the contact plate in the untripped state no potential. hereby the air and creepage distances can lead to potential Parts are reduced, which reduces the switching path and the Arc duration of the switching arc extremely shortened.

in the disconnected state bridges the ring contact the two differently potentialed contact clips, allowing a very good heat dissipation over the contact bracket or the adjoining Clamp connections is present. Thus, the device can also very permanently cause high short-circuit currents.

The Invention is not limited to the application in connection with varistors limited. Due to the fact that it is in the untriggered state due to the function in contrast to a separating device no load with the over the overvoltage protection element derived surge current and no appropriate interpretation is necessary, can z. B. also lightning current carrying spark gaps with a Fixing device according to the invention are provided, by z. B. whose jacket tube serves as a heat indicator, the over with a metallic wire or a plastic thread a Lotstelle or other separation point is connected. So can too in case of spark gaps in case of overload, thermal destruction the local isolation distances are prevented.

In summary So it is assumed that a short-circuiting, the one moving conductive or conductive Includes short-circuiting having which under mechanical prestressing by a fixing device is held, wherein the fixing device when heated releases the short circuiter so that it bridges the surge arrester connection contacts or connects. According to the invention, the fixing device in a place with determined strongest warming in case of overload directly on or on the surge arrester arranged and has a minimized heat capacity. Neither the short circuiter nor the fixing device are parts the current-carrying elements in normal operation, d. H. in the case of operation potential-free.

The Fixing device is in a first embodiment one with a solder or a heat-soluble adhesive held blocking element. In a second embodiment the fixer is a with a solder or a heat-soluble adhesive held wire or thread.

at A third embodiment is the fixing device a length-variable at temperature load, melting or dissolving wire or thread.

The Invention will be described below with reference to embodiments as well as figures are explained in more detail.

in this connection demonstrate:

1 a block diagram and a schematic diagram of a thermal separation device of the prior art, these being a series circuit of the separation device 2 with a varistor 1 represents;

2a and 2 B Schematic representations of a first embodiment of the invention with a movable tongue as an element of the short-circuiting device;

3 Representations of an embodiment with a movable contact piece for the short-circuiter, which is under spring tension and is fixed by a wire or thread using a temperature-sensitive material directly or indirectly to the surge arrester, in the state not triggered (right side) and triggered (left side);

4 an embodiment in which a varistor is provided with a conventional separating device analogous to the prior art and wherein additionally a short-circuit device analogous to the solution according to 3 is present;

5 an embodiment in which a surge arrester in the form of a varistor is provided with an additional enclosure and wherein the fixing device is located in an area in which collect and bundle in the event of a resulting arc temperature and / or gas effects of the arc;

6 a concrete example of a short-circuiting device with a spring-biased fixing device together with contact plates and contact plate in the untripped condition;

7 a representation similar to that after 6 , but in tripped condition;

8th a plan view of the ring contact and the anchorage for the wire of the fixing device according to the illustrations 6 and 7 and

9 an embodiment similar to the principle according to 6 and 7 , but adapted for use with a surge arrester in the form of an encapsulated spark gap.

As set forth in the introduction to the description, the prior art discloses thermal cut-off devices according to 1 previously known. Here is the actual separation device 2 in series with the varistor 1 which forms the surge arrester.

A separation strip 3 in the form of a movable switching tongue is under the force of a symbolically indicated spring F. A connection 6 of the varistor 1 is about a Lotstelle 5 with one end of the tear strip 3 connected, with the separation strip 3 with the second varistor terminal 7 in contact. In addition, there is a bottleneck 4 in the course of the separation strip 3 present, which acts as a current fuse.

When the varistor heats up 1 in the area of the Lotstelle 5 The solder melts with the consequence of a corresponding movement of the spring biased separating strip 3 from the varistor connection 6 path.

Like in the 2a illustrated, this device of the prior art can be developed according to the invention.

Here is just another contact capable of carrying continuous current 18 present, with a corresponding pole of the varistor 1 communicates. The contact 18 is arranged so that there is a sufficient separation distance between the different potentials.

On the area of the varistor 1 with the strongest heating is a thermally sensitive part or material 11 appropriate. The part 11 can be fixed to it either by a wax, by glue or solders whose melting point is slightly above the operating temperature of the varistor. But it can also be the part 11 even made of such a material. The part or the material 11 hold directly or in connection with spacers, z. B. in the form of a clamping pocket 10 , the moving part 3 the short-circuiting device. The connection to the varistor connection 6 and the moving part 3 (Separation strip after 1 ) becomes loose and lotus free at the with the reference sign 8th marked spot produced.

In the case of a corresponding heating of the fixing device, consisting of the part 11 , The latter is due to the spring force of the separating strip 3 (Moving part) pushed away and there is a short circuit between the moving part 3 and the additional contact 18 her (see 2a , right part of the picture).

The 2 B shows a perspective view of the solution as in the 2a shown in principle, with a clamping pocket 10 for the moving part 3 and a fixing device in the form of a retaining bolt 11 , For reasons of clarity, the additional contact with permanent current bearing was 18 omitted in the illustration.

Like in the 3 recognizable, in a further embodiment of the invention is a movable contact piece 15 present, the two separate gegenpolige contact pieces 16 can bridge. The separate contact pieces 16 each with one connection of the varistor 1 (Connection 6 and 7 ) in connection.

The movable contact piece 15 is using a spring 14 kept under tension. The bias state is fixed by a wire 13 is present with low heat capacity, which with the help of a temperature-sensitive material 12 how solder or wax can be fixed at a position of the varistor, which is subject to the strongest heat in the event of overload.

When the melting temperature of the material 12 is reached, the wire or thread dissolves 13 and it may be the movable contact piece 15 on the opposite polarity contact pieces 16 so that the desired short circuit and a current commutation to the short-circuit bypass ( 3 , right picture).

The embodiment according to 3 can, as in the 4 shown, also in addition to a conventional thermal separation device, such as 1 explained, be provided, ie combined.

In the embodiment according to 4 a known separation device of the prior art is combined with a short-circuiter according to the invention and thus increases the functional range of the arrangement. With a gradual aging or a slightly excessive mains voltage, the separating device responds after a few seconds or a longer time and the arrester is disconnected from the mains as usual. For heavy overload, in which the risk of destruction of the varistor within a very short time z. B. <1 s, the varistor is bridged by the short-circuiting device and separated by the upstream overcurrent protection device. This can z. B. be realized in that the melting temperature of the solder of the separation device is below the reaction temperature of the temperature-sensitive material of the short-circuiting device. In addition, an implementation can also be made via a corresponding vote of the heat capacities.

For very steep and high overvoltages or surge currents, in which the varistor 1 can be overloaded within a few microseconds, takes place before the destruction of the varistor 1 As a rule, no warming takes place. In these cases, a solution according to 5 proposed. This is the varistor 1 with a sheath 17 surround. An erosion resistant contact plate 20 of the varistor 1 leads to a first varistor connection 7 , with one of the opposite polarity contacts 16 communicates. The second varistor connection 6 leads to the second of the opposite pole contact pieces 16 , The temperature-sensitive material 12 which is the wire or thread 13 as a fixing device secures, holds the tension of the spring 14 upright, so that in the untripped condition, the movable contact piece 15 at a sufficient distance from the opposite pole contact pieces 16 located.

Does it come to the creation of an arc 19 , the hot gas or plasma follows the arrow-symbolized path along a chimney 21 , Thus, in this case, the temperature-sensitive material 12 are heated and a triggering movement of the movable contact piece 15 respectively.

Alternatively, there is the possibility of the material of the wire or thread 13 in such a way that it melts in the event of an arc or extends such that an electrical bridging of the opposite pole contact pieces 16 under the effect of the movable contact piece 15 becomes possible.

When in the 5 The embodiment shown is the movable contact piece 15 also formable as a lid, with a bellows 14 may be provided, which is the space below the lid 15 almost tightly closes. The lid is then virtually with overhangs over the fireplace 21 inverted and a piston is created, which responds to the pressure effect of the arc. The pressure increases the mechanical strength of the wire or thread 13 or the connection point exceeded even without an elevated temperature and the short-circuiter is triggered purely mechanically. This is particularly advantageous for a very rapid potential destruction of the varistor, since a detour over the heating is no longer needed.

The wire 13 does not have to be designed as an electrode. However, it is of advantage that the wire has a potential if necessary, so as to represent a lucrative way for the arc, so that the wire can be burned by the action of arcing and thus releases the actual short-circuiter. The wire is not necessarily to be regarded as a power supply to the varistor and is also not in the main current path.

The explained embodiments are characterized characterized in that the functional parts of the thermal tripping function from the live connection parts both physically as are also functionally separated and thus in their respective function can be optimized.

In the embodiments of the 6 to 8th is from a varistor to be secured 100 gone out, which is a first connection point 800 '' and a second connection point 900 '' includes. Both connection points 800 '' and 900 '' are about the connections 800 and 900 on a carrier plate 500 fixed with the help of screw connections.

The fixing device exists in the embodiments 6 to 9 from a wire 300 ,

An end of the wire 300 is with a solder or a heat-soluble adhesive 400 on the varistor 100 or the corresponding contact surface fixed. The other end of the wire 300 is about anchoring 101 on a contact plate 600 held. In this condition ( 6 ) is the compression spring 200 strained, ie it acts a bias on the contact plate 600 with ring contact thereon 700 ,

The contact plate 600 consists in the example shown of a mechanically and thermally highly resilient insulating material, preferably glass fiber reinforced epoxy resin and has at its outer edge region an annular metallic coating, ie the ring contact 700 on. This metallic coating or the metallic short-circuit ring soldered thereon in the tripped state provides the intended short-circuit connection to the contact clips 900 ' and 800 '' dar. The distance between the ring contact 700 and the opposite shorting bar 900 ' and 800 ' is indicated as switching path S.

By the design of the contact plate 600 the heat dissipation takes place only over the wire 300 , which is negligible due to its low thermal conductivity and the existing low mass. The wire 300 can also be replaced by a plastic thread, instead of the Lotstelle under Heat effect through the varistor 100 melts and so the biasing force of the contact plate 600 free.

The design of the contact plate 600 with the ring contact 700 and the wire fixed in the center 300 about anchoring 101 creates, as in the 8th shown a sufficiently large isolation distance Is in both electrical and thermal terms.

When triggered, the ring contact bridges 700 the two differently potentialed contact clip or shorting bar 800 ' and 900 ' , This results in a very good heat dissipation over the contact clip and the adjoining clamp connections, so that the inventive solution is able to permanently lead very high short-circuit currents.

Another advantage of the presented short-circuiting device is that it is not limited to the application in connection with varistors. Due to the fact that the device in the untripped state, in contrast to a separating device, is not loaded with the surge current to be dissipated via the overvoltage protection element and, consequently, does not have to be designed for this, it is possible, for example. B. also lightning current carrying spark gaps 120 ( 9 ) are provided with the elements of the invention by z. B. on the spark gap 120 a copper sleeve is applied and the corresponding solder joint 400 is created. So here it serves the jacket tube of the spark gap as a heat indicator.

In the presentation after 9 with respect to a short-circuiting device for a spark gap 120 are more ideas relevant to the invention embodied. So takes the contact plate 600 not just the ring contact 700 but an additional optical signaling device 110 , z. B. in the form of a signal button. If the short-circuiting device is active, the signal button also moves in the illustration shown 9 upwards and thus enters the area of a viewing window 130 one. This is an optical visualization of the given short circuit. The viewing window 130 can be the upper end of an installation enclosure 140 Form (series connection housing).

1; 100

varistor

2

cut-off

3

tear-off strips; moving part

4

bottleneck

5

solder joint

6 7

varistor

8th

loose, Lotlose connection

9

Connection between varistor connection 7 and separating strips 3

10

glassine envelopes

11

retaining bolt

12

temperature-sensitive Material such as solder, wax or the like

13

wire

14

feather

15

portable contact piece

16

separate opposite pole contact pieces

17

flameproof jacket

18

contact piece

19

Electric arc

20

erosion-resistant contact plate

21

fireplace

200

compression spring

300

wire

400

Lot-separation point; Lot-release device

500

Ladder- and / or carrier plate

600

contact plate

700

ring Contact

800

first outer connection

800 '

first Shorting bar

800 ''

first Connection point varistor / spark gap

900

second outer connection

900 '

second Shorting bar

900 ''

second Connection point varistor / spark gap

101

anchoring for wire or thread

110

signal button

120

radio link with copper cuff

130

window

140

installation Enclosures

F

force action a spring

is

insulating gap

S

/ Switching range

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - DE 4241311 A1 [0002]
• - DE 3805889 A1 [0002]
• - DE 3318588 A1 [0004, 0006]
• DE 3734214 A1 [0004, 0008]
• - DE 2634479 [0004]
• - US 4068281 [0005]
• - EP 0860927 A1 [0005]
• - DE 2634479 A1 [0007]

Claims (10)

Short-circuiting device for surge arresters such as varistors, spark gaps or the like means comprising a movable conductive or conductive sections having short circuiter, which is held under mechanical bias standing by a fixing device, the fixing when heating the short-circuiter releases so that it bridges the surge arrester connection contacts or connects, characterized in that the fixing device is arranged at a point with determined or strongest expected heating in case of overload directly on or on the surge arrester and has a minimized heat capacity. Short-circuiting device according to claim 1, characterized in that the fixing device with a Lot, a heat-soluble adhesive or wax held Blocking element is. Short-circuiting device according to claim 1, characterized in that the fixing device with a Lot, a heat-soluble adhesive or wax held Wire or thread is. Short-circuiting device according to claim 1, characterized in that the fixing device at a temperature load variable in length, melting or dissolving Wire or thread is. Short-circuiting device according to one of the preceding Claims, characterized in that the fixing device is located in the area of an additional housing of the surge arrester, in the case of a developing arc, this area and / or gas effects of the arc collects or bundles. Short-circuiting device according to claim 3 or 4, characterized in that the wire or thread-like Fixing device with its first end on the surface of the surge arrester and with its second, opposite end with a contact plate in conjunction stands and runs inside a biasing spring. Short-circuiting device according to claim 6, characterized in that the connection of the first end of the Fixing device with the surface of the surge arrester through the heat-soluble adhesive, the solder or Wax takes place. Short-circuiting device according to claim 6 or 7, characterized in that the contact surface of a mechanically and thermally loadable insulation material, on the free outside surface of a contact strip or contact ring is made of conductive material. Short-circuiting device according to claim 8, characterized in that the connection elements of the surge arrester each with a contact bracket in conjunction, which in the direction of the contact strip or contact ring of the contact plate extend. Short-circuiting device according to claim 1, characterized in that neither the short circuiter nor the fixing parts of the current in normal operation case Elements of the surge arrester are.