EP3669951A1 - Electrically triggered melt solder opening element of an extinguishing fluid conducting element - Google Patents

Abstract

There are a large number of different sprinklers which are used in fire-fighting systems, in particular water extinguishing systems with a locked and unlocked state, the extinguishing fluid-conducting element having a fusible link opening element with a predetermined electrical resistance, the fusible link opening element being integrated in an electrical circuit which has a switch (S) and through which current flows when the switch (S) is closed, through which the fusible link opening element is opened.

Description

There are a variety of different sprinklers that are used in fire fighting systems.

Known are among others fusible link sprinklers, or also sprinklers with a "thermally triggering glass ampoule" also called "thermo bulbs". Such thermo bulbs are standard in the sprinkler industry.

With the Thermo Bulb principle, a closed glass ampoule with at least one medium, e.g. B filled with gas or at least two media (liquid and glass bubble). When heated, the gas and / or liquid expands and a pressure is built up inside the glass ampoule until a threshold value is reached at which the glass ampoule bursts / bursts and thus releases the sprinkler function and the fluid extinguishing agent flow. The glass ampoule itself is also mechanically biased, i.e. H. it presses on a closure that is exposed to the water pressure in the pipeline on the overlying side.

The situation is different with fusible link sprinklers, in which the fusible link is under mechanical prestressing, so that when the temperature in the outer vicinity of the fusible link, e.g. B. due to an existing fire or another thermal Event is heated, the solder at a defined temperature softens, melts, or the like and thus yields the solder due to the mechanical bias and releases the sprinkler function and the fluid extinguishing agent flow.

Under certain conditions, the sprinkler function, i. H. Firefighting with the sprinkler is already released before an actual fire event takes on larger proportions and before the thermal energy of the fire event triggers the known sprinkler. In addition, if the fire spreads quickly, it can also make sense to use sprinklers to trigger the actual fire, e.g. carry out a pre-wetting.

In this context, reference is made to the state of the art WO2017 / 105289 .

This prior art discloses a sprinkler with a glass bulb (thermo bulb principle) and on the outside of the bulb an electrically conductive coating, which forms an electrical resistance (R), is applied, which, if necessary, by closing a switch and applying a voltage can be flowed through by a current.

As a result, the glass bulb and thus the medium of the glass bulb are heated until a thermal limit is reached, at which point the glass bulb bursts, thus releasing the sprinkler function.

However, the aforementioned solution is very complicated, especially the production of the glass barrel and the electrically conductive coating, which at the same time forms an electrical resistance, is very complex and causes additional costs.

Finally, it also has the disadvantage that if the sprinkler is stored as part of a fire-fighting system under a ceiling or on a wall for years or even decades, it is possible that dust, cobwebs or other influences will settle on the glass bulb and in the event that then the electrical triggering of the sprinkler is required, a part of the current not through the layer on the outside of the glass bulb, but otherwise z. B. over cobwebs or "shorts" formed from dust or material, flows off.

It may then take too long until the medium in the glass bulb warms up and the glass bulb is "blown up".

The object of the present invention is to provide a solution for a soldering solder opening element for extinguishing fluid-conducting elements for a fire-fighting system, which enables greater reliability and functional reliability than the known solutions.

An extinguishing fluid-conducting element is, according to the understanding of the present application, for. B. a fusible link sprinkler or a control valve with fusible link opening element or another device in which the flow of the extinguishing fluid is made possible by triggering the fusible link opening element by means of a fusible link opening element.

The object is achieved with an extinguishing fluid-conducting element with the feature of claim 1.

Advantageous further developments are described in the subclaims.

Furthermore, the present application and invention also include a fire-fighting system with an extinguishing-fluid-conducting element, as well as a method for testing an extinguishing-fluid-conducting element.

The invention is based on the knowledge that the fusible link opening element regularly consists of electrically conductive parts and that by integrating the fusible link opening element in an electrical circuit, it is possible that not only the conducting parts of the fusible link opening element are flowed through by the current, but that the fusible link is doing so heated to a predetermined temperature, so that the fusible link opening element is opened and the extinguishing fluid-conducting element is thus triggered.

In a variant of the extinguishing fluid-conducting element, it is possible that an electrically operable thermocouple, for. B. a heating resistor, in contact with the fusible link or in close proximity to this.

If a current flows through the electrically heatable element by closing a switch, this heats up very strongly and causes the fusible link to melt, and as a result, the extinguishing fluid-conducting element is triggered. With this heating, the heating resistor can also be designed such that it virtually dissolves itself, such as a classic fuse.

The triggering of the switch does not necessarily have to assume a fire, but can also take place if another parameter in the space on the area where the extinguishing fluid-conducting element is arranged exceeds a predetermined value. If, for example, the room is equipped with a smoke detector, the switch can be closed if a predetermined smoke value is exceeded. In the event that a radiation sensor is installed, the switch is closed when a certain radiation value is exceeded. If a certain heat sensor is installed in the room, the switch closes when a certain room temperature is exceeded. In one of the aforementioned cases, a corresponding sensor, e.g. B. smoke, radiation, heat, temperature sensor, etc. a control function and causes the switch to close when a predetermined value, which is determined by the respective sensors, is exceeded.

The heating element is preferably electrically insulated from the outside, so that in the event that cobwebs, dust, textiles or other weaving materials should have deposited on the heating element, they cannot impair the electrical current flow.

Even after many years or decades where the sprinkler function has not been triggered, cobwebs, dusts, textile fibers etc. that are regularly in the air and also deposit on the fusible link cannot impair the electrical heating function of the thermocouple.

The invention is explained in the following exemplary embodiments and in drawings.

The following should be mentioned regarding the basic function:
The electrically heatable heating element z. B. heating resistor R is connected to a voltage source and an open switch S, by closing the switch S current I flows from the voltage source through the resistor R and then generates thermal energy there according to the formula "I ² R".

Switch S can already be closed when a fire has occurred but the temperature at the sprinkler is not yet high enough to trigger the sprinkler.

The voltage source can be a battery, but can also be the normal electrical supply network and it is possible that a switch z. B. in the fire alarm and / or extinguishing control center, a large number or a defined number of sprinklers for triggering.

It is also conceivable, for example, that if a large number of sprinklers are installed in a building, they are arranged in certain groups and the individual sprinklers can also be triggered in groups by triggering a switch (controlled from the fire alarm center), which is particularly important for the Fighting rapidly spreading fires is important.

But it is also possible to trigger all sprinklers at the same time with a single switching command.

Figur 1a:

Einen Querschnitt durch ein bekanntes löschfluidleitendes Element einer Brandbekämpfungsanlage

Figur 1b:

Eine Seitenansicht eines löschfluidleitenden Elements nach Figur 1a

Figur 2:

Eine Querschnittsdarstellung durch ein erfindungsgemäßes löschfluidleitendes Element in Ausbildung eines Schmelzlotsprinklers.

Figur 3:

Schematische Darstellung eines löschfluidleitenden Elements in Form eines Steuerventils mit Schmelzlotöffnungselements.

Figur 4:

Schematische Darstellung einer Zoneneinteilung eines Raums, bei dem verschiedene Bereiche mit Löschfluid versorgt werden können.

Figur 5:

Eine Querschnittsdarstellung einer alternativen Ausführung gemäß Figur 1a.

Figur 6:

Perspektivische Ansicht eines löschfluidleitenden Elements gemäß Figur 5.

The invention is also explained in the following with the aid of its examples in drawings. The drawings show

Figure 1a:

A cross section through a known extinguishing fluid-conducting element of a fire-fighting system

Figure 1b:

A side view of an extinguishing fluid-conducting element according to Figure 1a

Figure 2:

A cross-sectional view through an extinguishing fluid-conducting element according to the invention in the form of a solder sprinkler.

Figure 3:

Schematic representation of an extinguishing fluid-conducting element in the form of a control valve with a solder opening element.

Figure 4:

Schematic representation of the zoning of a room in which different areas can be supplied with extinguishing fluid.

Figure 5:

A cross-sectional representation of an alternative embodiment according to Figure 1a .

Figure 6:

Perspective view of an extinguishing fluid-conducting element according to Figure 5 .

Figure 1 shows in the two representations in Figure 1a and Figure 1b the cross section ( Figure 1a ) and the view ( Figure 1b ) of a known fusible link sprinkler with a fusible link trigger element.

Such a sprinkler 1 has a deflector 2, which is penetrated centrally by a screw 3. With this screw 3, the trigger mechanism 4 of the fusible link release element can be adjusted, which consists, for example, of a rod 5, a curved lever 6 mounted between the screw 3 and the rod 5, and two plates connected by a fusible link.

As in Figure 1a to recognize, the lever 6 with its front part 7 on a plate 8. On this plate 8 is a further plate 9, which in turn is received by the straight lever 5. In the meantime, the fusible link 23 is located and initially connects the two plates.

The straight lever 5 has a foot end 10, which lies on a base 11, which in turn is received by a receptacle 12 (a so-called pip cap). Furthermore, each lever has a head end 25, which lies in a recess 26 of the lever 6. This receptacle 12 has a circumferential shoulder 13 which on a spring 16 z. B. Belleville washer (Belville), which is circular and comes on the outside on the frame of the sprinkler body 14 to the system. The sprinkler body 14 has a thread 15 in the lower area, which can be screwed into a pipe through which water or other fluid extinguishing agent is brought to the sprinkler and since the sprinkler body 14 is hollow on the inside, the fluid extinguishing agent (Flm) presses against the receptacle 12 and the spring 16 from the inside.

The spring 16 is coated with Teflon in order to develop the highest possible sealing effect, because as long as the sprinkler release mechanism 4 is still in the sprinkler 1, a sufficient force must be opposed to the pressure of the fluid extinguishing agent (Flm) and at the same time the fluid extinguishing agent must not come out of the Escape inside the sprinkler body 14.

Figure 1b shows the side view of the in Figure 1a Sprinklers shown.

This clearly shows that the sprinkler body 14 has an O-shaped frame 16 which supports the deflector 2. The frame 17 is part of the sprinkler body 14 and as can be seen, the screw 3 passes through the frame 16 where the deflector is also held by the frame.

Now screw 3, as in Figure 1a and 1b shown, tightened (ie moved downwards in the picture), it presses (tensions) the release mechanism 4 and over the foot region 10 of the rod 5 into the base. At the same time, the receptacle 12 is pressed against the inner lying area of the spring 16 and as a result the spring 16 also lies with its outer area sealingly on the sprinkler body 14.

As in Figure 1a can also be seen, the connection between the rod 5 and the lever 6 is arranged slightly offset from the ventral axis Z. By tightening the screw 3, a force is thus also exerted on the lever 6, the outer region of which would like to move away from the rod 5.

However, this is prevented by connecting the two plates 8 and 9 to a fusible link 23.

Depending on the application, location, type and desire, the fusible link can be designed so that it melts at a desired temperature, and if this is the case, the plates 8 and 9 separate from one another, ie the front part 7 of the lever 6 moves outwards (in Figure 1a to the right towards 24) and the entire trigger mechanism falls out of its as in Figure 1 Locking shown with the result that no pressure from the outside opposes the internal pressure of the fluid extinguishing agent and this therefore flows from the inside of the sprinkler body 14 and preferably sprayed onto the deflector 2, which ensures that a desired spray plate is set.

Figure 2 shows an inventive development of the known sprinkler.

The following preliminary remarks are made here.

Ideally, when the fusible link melts, all parts of the trigger mechanism detach from the sprinkler so as not to disrupt or distract the fluid flow of the extinguishing agent.

The sprinkler body 14 is regularly made of metal, e.g. B. brass, the deflector is also made of metal, for. B. phosphor bronze, the base 11 is also made of metal, for. B. brass, the screw 3 is also made of metal, for. B. stainless steel and the lever 5 and 6 are also made of metal, e.g. B. stainless steel. The two fusible plates 8 and 9 are also made of metal, for. B. a nickel-beryllium alloy and the receptacle 12 is also made of metal, for. B. brass or copper.

The spring 16 is also made of metal, but is z. B. coated with polytetrafluoroethylene (Teflon). This means that the receptacle 12 lying on the spring 16 is electrically non-conductively connected to the sprinkler body 14.

Furthermore, in Figure 2 Now it can be seen that the frame of the sprinkler body 14 is at least but the screw 13 is connected via an electrical line to the pole of a voltage source. A further line connects in the foot region 10 of the lever 5 to the other pole of the voltage source 27. It can be seen in the illustration that the electrical line is produced between the foot region of the lever 5 and the voltage source 27 via the electrically conductive base 11, which is electrically conductively connected to the receptacle 12 to which the first electrical line 18 is clamped. The second electrical line 19 can, however, also be attached or connected to the frame of the sprinkler 14 directly on the screw 3 or the head end 25 of the trigger mechanism 4 or another part of the sprinkler body (e.g. screwed, soldered, etc.). ).

It can also be seen that a switch S is formed, which in the Figure 2 is in the "open position". Finally, by closing the switch S, current can flow through the frame of the sprinkler body, the metal parts of the trigger mechanism connected to it with the base 10 and receptacle 12, which, as mentioned, consist of electrically conductive materials.

A current then flows through the frame of the sprinkler 14, through the screw, the levers 5 and 6, and through the plates 7 and 8.

In the event that the second electrical line 19 is attached to the frame 14 or on the screw 13 or on the lever 6 and between the head end 25 of the rod 5 on the one hand and the trough 26 of the lever 6 on the other hand, an electrical insulation is attached, in which, for . B. there an electrically non-conductive material or seal, for. B. plastic is attached, then the electric current flows alone through the lever 6 and plates 8, 9 and the solder 23 to the foot region 10 of the rod 9, so that the maximum current through the plates 8, 9 and the solder 23 flow can, in order to bring the temperature of the solder to the melting temperature as quickly as possible.

Since, as mentioned, the spring 16 is coated with Teflon, this spring 16 electrically isolates the receptacle 12 from the frame of the sprinkler 14.

As a result of the current flow, the levers 5 and / or 6 and / or the plates 8 and 9 and possibly also the fusible link 17 which connects the plates heat up instantaneously, so that the triggering mechanism is triggered and released almost immediately , because the solder can be melted very quickly with the flow of the current.

So that the known fusible link sprinkler, that is, an "electrically triggerable function", all that is required is a line connection and a closed circuit, for. B. on the receptacle 12 and the sprinkler frame 14, 17th

When the switch S is closed, a current I flows from the voltage source or current source (voltage source can be a DC voltage or an AC voltage current). By integrating the extinguishing fluid-conducting element into the circuit shown, the current also flows through the levers 5 and 6. or the plates 8 and 9 and the solder 23 located between them. The solder material is preferably one which has a specific electrical resistance.

Typical material for the fusible link is beryllium nickel UNS-N03360. Such a beryllium nickel alloy has a specific electrical resistance of 28.7 to 43 µ cm. Another solder material with an even greater specific electrical resistance is also suitable according to the invention and then leads to an even faster melt, so that an even faster triggering is possible.

In addition, if the rod 5 and the lever 6 also heat up due to the current flowing through them, as mentioned, this leads to a very rapid reaching of the melting temperature of the solder and then to a quasi electrical triggering of the designated solder sprinkler.

In Figure 2 is not shown that the switch S by a sensor, for. B. controlled a harsh, radiation or temperature sensor, ie can be closed when a value detected by the sensor exceeds a predetermined value.

Figure 3 shows the application of the invention also for a control valve with an input line 20 and two output lines 21, 22. These lines are designed for the fluid extinguishing agent flow. As in Figure 2 to recognize, the trigger mechanism 4 is again formed between two pressure points.

In Figure 3 is the fusible link opening element - this is indicated by the circular representation - as designed according to Figure 2 .

While the two pressure points in the Figure 1 form the screw 3 and the base 11 of the receptacle 12, the pressure points exist after Figure 2 again from a screw 30 and a valve tappet 31. The valve tappet 31 presses (from below) onto a plate 32 which on the one hand rests on a counter bearing 34 of the control valve and on the other hand accommodates the trigger mechanism 4.

In the interior of the control valve, the valve tappet 31 closes the flow of a fluid extinguishing agent with its rear part, which is not visible in the figure, and its pressure is applied to the lower connection of the control valve.

If the trigger mechanism by closing an electrical switch S as with the same or similar functionality as in Figure 2 described, triggers, is moved by the fluid pressure of the valve tappet and thus releases the flow of the fluid extinguishing agent through the two outlets 21 and 22.

As an alternative to the solution shown Figures 2 or 3rd it is also possible for a heating wire resistor to be connected to or arranged close to the fusible link and if a current then flows through the heating wire resistor, the resistance heats up and thus causes the fusible link to melt.

It is a further preferred embodiment if the fusible link or the two plates 8 and 9, which are connected by means of the fusible link, are made from a material which has very good heating wire resistance properties, that is to say a high specific resistance, so that when these parts flow through, with As much heat as possible is generated which quickly melts the solder.

The thermal heating element (heating sealing resistor) can be constructed as a heating resistor or in the manner of a fuse (such fuses are state of the art), which means that when the fuse flows through it is not only sufficient Heat for melting the fusible link is generated, but the fuse also destroys itself (tears open).

The fuse is designed so that a predetermined current can flow through it for a predetermined period of time, and this is designed such that enough heat is generated on the one hand for reliable melting of the solder, but on the other hand also for melting the fuse.

Another variant is that the solder itself is electrically conductive and / or magnetic and is surrounded by a coil which, when a current flows through the coil, applies a force to the solder, which tears it, or which in turn melts the solder heated to such an extent that it melts almost instantaneously and thus releases the sprinkler or valve function.

In Figure 4 the elevation of an area is shown, which is divided into 4 sectors a, b, c, d. Each sector is assigned a corresponding switch S1, S2, S3, S4, so that, if necessary, the corresponding sprinklers of a sector can also be activated by closing the corresponding switch, that is to say that with a single switch command, e.g. B. with the closure of switch S1, the sprinklers of sector a begin almost simultaneously to bring water to the area of sector a.

It is of course also possible with a single switch that is in the Figure 3 is arranged as switch S5 to bring all sprinklers of all sectors to activation.

The switches can be located in the fire alarm and / or extinguishing control center (BMZ), but can also be spatially assigned to the individual sectors so that they can be triggered by the appropriate personnel if a fire develops. However, the individual assignment of switches to the sprinklers is also conceivable.

So far in Figure 2 the solution according to the invention for a direct voltage / direct current source is shown, it should be pointed out that the invention works equally well with an alternating voltage / alternating current source.

The voltage / current-carrying cables to the sprinkler can be attached to the sprinkler or its supply parts (such as sprinkler pipes) either detachably (e.g. by screwing) or non-detachably (e.g. welding, soldering, gluing), as is one Clamp bracket possible. It is important that there is an electrically conductive contact between the current / voltage-carrying cables and the connected components of the sprinkler are guaranteed at all times, so that when the switch is closed, the current mentioned can flow in order to melt the solder and thus trigger the sprinkler.

The division of an area into different sectors, e.g. B. in a large hall, in a large building, etc. is known as such, for. B. from US 2017/0120090 , Figure 1 . However, it is not known from this document that individual sectors are also assigned corresponding switches, by means of which an electrical triggering of the sprinklers provided can be made possible.

The invention also includes the possibility that the electrical conductivity is tested in a test mode by (for a short time) a small test current flowing through the line and by measuring the existence of the electrical contacts and the conductivity of the current by the defined current part becomes. The resulting current is measurable, but it is not sufficient to melt the solder.

Such a check can also be routinely carried out at recurring intervals, e.g. B. once a week, once a year, etc., and the test result can be logged, saved and / or displayed on a corresponding display of the fire alarm and / or extinguishing control center (BMZ).

As mentioned, a test cycle is designed so that a current flows through the current-carrying parts which is significantly lower than current by means of which the soldering sprinkler can be triggered electrically.

For example, if the current for electrically triggering the fusible link sprinkler is 10 A, then a significantly lower test current is a current of the order of 10%, that is 1 A or less, e.g. B. 1 mA. It is crucial that the test current can still be measured safely in the test cycle.

The test cycle according to the invention also has the advantage that damage to the sprinkler can be determined under certain circumstances. An aging of the components of the sprinkler can also be determined with this, namely when the components of the sprinkler through which the current flows assume an increased or decreased resistance due to their aging, which can also happen due to material setting, material oxidation and other aging influences.

It is possible to determine from the test cycle whether a sprinkler was exposed to too high a temperature when it was transported to the installation site. If this was the case, an invisible detachment of the two plates can occur, which reduces the electrical conductivity, which can be determined in the test cycle.

Figure 5 shows a cross section through an alternative arrangement or design of a solder sprinkler. The reference numerals relate to the parts that are also in Figure 2 are described.

It should be noted that the mechanical structure and thus the mechanical structure of the in Figures 5 and 6 Sprinklers shown is known as such, e.g. B. from US-A-4,623,023 . In Figure 5 it is shown how such a sprinkler can be equipped so that it can also be triggered electrically.

The only essential difference is the design and arrangement of the rod 5, the lever 6 and the plates 8 and 9. As in Figure 5 can be seen, the plate 9 is an integral part of the rod 5, while the plate 8 is an integral part of the lever 6. As in Figure 5 can be seen, the rod 5 is arranged slightly inclined from the central axis Z, so that the screw acts on the front part of the lever 6, so that tightening the screw of the lever with its plate 8 tries to move away from the rod or its plate 9 to move. This is prevented by the fusible link 23 located between the plates 8 and 9, as long as it is still in a solid state and as long as this fusible link is not yet heated to its predefined release temperature. If this is done by closing the switch S, a current I then flows through the electrical circuit, in which the fusible link opening element is integrated.

Figure 6 shows a perspective view of the solder sprinkler according to Figure 5 .

It can be clearly seen in the figure that the outer structure of the soldering sprinkler has a structure similar to that of Figure 1b Known structure that the essential difference is only the formation, shaping and arrangement of the levers 5 and 6 and the plates 8 and 9, which are connected by the fusible link.

It is also pointed out that an electrical check as to whether a fusible link sprinkler is functional and is known as such is e.g. B. from US 2017/0120090 . However, the solution shown in this prior art is extremely complicated and allowed only the technical function check, but not the electrical triggering of a solder sprinkler.

As shown in the present application, however, the technical function control can also be carried out with the devices for electrically triggering the solder sprinkler when the electrically conductive parts are only subjected to a low test current, as mentioned, but without solving the sprinkler cause.

Thus, the configuration and structure of the extinguishing fluid-conducting element according to the invention also enables a method for testing the extinguishing-fluid-conducting element to be carried out, a test cycle being provided in which a test current flows through the electrical circuit, the test current being significantly lower, i. H. e.g. B. is less than 10%, 5% or less than the current for triggering the fusible link opening element and wherein in the test cycle the contacts and / or aging or by functionality of the extinguishing fluid-conducting element or the fusible link opening element are checked, it is determined, for example, in the test cycle that the Test current does not flow through the electrical circuit, it can be assumed that there is a clock interruption, e.g. B. there is a line break so that in such a case a targeted error check or maintenance can take place.

Thus, the very complex test structure as it is based on US 2017/0120090 is known to be dispensed with entirely and a simpler solution will be provided which at the same time has at least two functions, namely on the one hand to carry out the function test of the sprinkler and on the other hand to carry out its electrical triggering.

Reference list

1

Soldering sprinkler

2nd

Deflector

3rd

screw

4th

Trigger mechanism

5

pole

6

lever

7

Front part

8th

1st plate

9

2nd plate

10th

Foot end

11

document

12

admission

13

shoulder

14

Sprinkler body

15

thread

16

feather

17th

frame

18th

1. Management

19th

2nd line

21st

1. Output line

22

2. Output line

23

Fusible link

24th

Outward direction

25th

Headboard

26

trough

27th

Voltage / current source

30th

screw

31

Valve lifter

32

plate

34

Counter bearing

S

counter

Claims (6)

Extinguishing fluid-conducting element for a fire-fighting system, in particular water extinguishing system with a locked and released state, the extinguishing-fluid-conducting element having a soldering solder opening element with a predetermined electrical resistance, the melting solder opening element being integrated in an electrical circuit which has a switch (S) and through which when closed of the switch (S) current flows through which the fusible link opening element is opened. Extinguishing fluid-conducting element according to claim 1, characterized in that the solder opening element has melting solder and softens, melts, disintegrates or the like by flowing the electric current through the solder opening element. Extinguishing fluid conducting element according to one of the preceding claims, characterized in that the extinguishing fluid conducting element has a thermal resistance which touches or is arranged in the immediate vicinity of the soldering solder opening element and which is integrated in the electrical circuit and which is closed when the switch (S) closes a predetermined amount generated at thermal energy by means of the temperature defined by the solder, so that the parts of the solder opening element, which are held together by the solder, separate. Extinguishing fluid conducting element according to one of the preceding claims, characterized in that the extinguishing fluid conducting element is a soldering sprinkler or a control valve with a melting solder opening element. Fire-fighting system, in particular a water extinguishing system with a locked and released state with an extinguishing fluid-conducting element according to one of the preceding claims. Method for testing an extinguishing fluid-conducting element according to one of the preceding claims, characterized in that a test cycle is provided in which a test current flows through the electrical circuit, the test current being significantly less than the current for triggering the soldering solder opening element and wherein contacts and / or aging or functionality of the extinguishing fluid-conducting element or of the fusible link opening element are checked.

Images