Water extinguishing system and method for controlling a pump test run in a water extinguishing system

Abstract

The invention relates to a water extinguishing system with a fluid supply for providing an extinguishing fluid, a pump which is configured to pump the extinguishing fluid from the fluid supply into a supply line of a pipe system of the water extinguishing system, a test line which branches off from the supply line of the pipe system and is configured to conduct the extinguishing fluid pumped by the pump away from the pipe system, and a fluid bypass line with a cross section reduced in comparison to the cross section of the test line, where the fluid bypass line is configured to conduct a predefined portion of the extinguishing fluid around an opening element of the test line away from the pipe system, where the water extinguishing system further comprises at least one control device which is configured to determine at least one parameter indicative of the cross-section of the fluid bypass line, and to control the pump test run of the pump on the basis of that parameter. The invention further relates to a corresponding control device and a method for controlling a corresponding pump test run.

Claims

1. A water extinguishing system comprising: a fluid supply for providing an extinguishing fluid; a pump which is configured to pump the extinguishing fluid from the fluid supply into a supply line of a pipe system of the water extinguishing system, a test line which branches off from the supply line of the pipe system and is configured to conduct the extinguishing fluid pumped by the pump away from the pipe system, wherein the test line has an opening element, which is configured to be movable between a locking position, in which the opening element closes the test line, and an unlocking position, in which the opening element opens the test line, and a fluid bypass line which in comparison with the test line has a reduced cross-section and is configured to conduct a predefined portion of the extinguishing fluid around the opening element away from the pipe system, wherein the water extinguishing system further comprises: at least one control device which is configured to determine at least one parameter value of a parameter indicative of the cross-section of the fluid bypass line and to control a pump test run of the pump on the basis of the parameter value dependent on whether the fluid bypass line can sufficiently conduct the extinguishing fluid pumped by the pump during the pump test run away from the pipe system.

2. The water extinguishing system according to claim 1, wherein the fluid bypass line is configured to branch off from the test line or from the supply line of the pipe system.

3. The water extinguishing system according to claim 1, wherein controlling the pump test run comprises comparing the parameter value with a predetermined threshold value, wherein the control device is configured to terminate the pump test run and/or to not start the pump test run if the threshold value is exceeded or not reached.

4. The water extinguishing system according to claim 1, wherein the control device is configured to ensure a state of operational readiness of the water extinguishing system in the event of an energy failure during the pump test run.

5. The water extinguishing system according to claim 1, wherein the control device is configured to ensure an operating state of the water extinguishing system in the event of fire during the pump test run.

6. The water extinguishing system according to claim 1, further comprising an input device configured to receive an automated input causing the pump to start the pump test run.

7. The water extinguishing system according to claim 1, wherein the control device comprises at least one flow sensor, and wherein the parameter indicates a flow volume of the extinguishing fluid per unit of time through the fluid bypass line.

8. The water extinguishing system according to claim 1, wherein the control device comprises at least one pressure sensor, and wherein the parameter indicates a differential pressure of the extinguishing fluid through the fluid bypass line.

9. The water extinguishing system according to claim 1, wherein the control device comprises at least one noise sensor, and wherein the parameter indicates a noise output of the pump indicative of a state of the pump.

10. The water extinguishing system according to claim 1, wherein the control device comprises at least one vibration sensor, and wherein the parameter indicates a vibration state of the pump indicative of a state of the pump.

11. The water extinguishing system according to claim 1, wherein the control device comprises a switching arrangement which is configured to switch between an activation position and a deactivation position, wherein the deactivation position represents an energetically more favorable state and is switched when a flow rate falls below a threshold value, and wherein the pump operation is terminated in the deactivation position.

12. The water extinguishing system according to claim 1, further comprising a temperature sensor arranged in the vicinity of the pump and configured to determine a temperature of the extinguishing fluid, wherein controlling, based on the parameter, comprises comparing a temperature value of the temperature of the extinguishing fluid in the vicinity of the pump with a temperature threshold value.

13. The water extinguishing system according to claim 12, wherein the control device is configured to terminate the pump test run if the temperature threshold value is exceeded.

14. The water extinguishing system according to claim 1, wherein the cross-section of the fluid bypass line is reduced by a value of more than 90% in comparison with the test line.

15. A hazard reporting center for the water extinguishing system according to claim 1.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention is described in more detail below with reference to the attached figures and using preferred embodiment examples. The figures show:

(2) FIG. 1 is a schematic diagram of a water extinguishing system according to a preferred embodiment.

(3) FIG. 2 is a schematic diagram of a water extinguishing system according to another preferred embodiment.

(4) FIG. 3 is a schematic diagram of a water extinguishing system according to yet another preferred embodiment.

(5) FIG. 4 is a schematic diagram of a water extinguishing system according to yet another embodiment.

(6) FIG. 5 is a schematic diagram of a water extinguishing system according to yet another embodiment.

MODE(S) FOR CARRYING OUT THE INVENTION

(7) FIG. 1 shows a water extinguishing system 1 according to a preferred embodiment of the invention. In this embodiment, the water extinguishing system 1 is a sprinkler system comprising a plurality of sprinklers 501, which are supplied with extinguishing fluid via a pipe system 500.

(8) The extinguishing fluid is provided by a fluid supply, which in the exemplary embodiment of FIG. 1 is designed as fluid supply tank 10. The fluid supply tank 10 is connected to the pipe system 500 via a supply line 2 in order to supply the pipe system 500 with extinguishing fluid.

(9) The supply line 2 is preferably implemented as a pipe in which a shut-off valve 101, a pressure indicator 102, a pump 20, a non-return valve 50 and a shut-off valve 51 are arranged. The pump 20 is used in this case to pump the extinguishing fluid from the fluid supply tank 10. In this embodiment, the pump 20 is designed as a sprinkler pump.

(10) A test line 3 branches off from the supply line 2 and comprises a shut-off element 31. In accordance with the prior art, this test line 3 was used to carry out a pump test run by moving the opening element 31 from a locking position to an unlocking position to open a test circuit.

(11) The test line 3 according to FIG. 1 is configured to conduct the extinguishing fluid pumped by the pump 20 into a fluid reservoir 11. In the specific embodiment of FIG. 1, this fluid reservoir is connected to the fluid supply tank 10 in fluid communication, such that the extinguishing fluid is conducted back to the fluid supply. In other embodiments, however, the test line 3 may also be configured in such a way that the extinguishing fluid conducted through it is lost to the extinguishing circuit by being conducted into a discharge.

(12) In the locking position of the opening element 31, the opening element 31 is positioned such that no fluid can flow through the test line 3. However, a fluid bypass line 4 branches off from the test line 3, which in the embodiment of FIG. 1 has a cross-section that is 98% reduced in comparison with the test line 3, i.e. has only about 2% of the cross-section of test line 3. This fluid bypass line 4 allows a small portion of the extinguishing fluid to flow around the opening element and thus to end up in the fluid reservoir 11.

(13) In the specific embodiment of FIG. 1, the fluid bypass line 4 branches off from the test line 3. In other embodiments, however, the fluid bypass line can alternatively or additionally also branch off from the supply line 2, as long as it allows some of the extinguishing fluid to be conducted around the opening element when the extinguishing fluid is pumped by the pump 20.

(14) The water extinguishing system 1 as shown in FIG. 1 further comprises a pump control 21 with a pressure switch 22. The pump control 21 is used to start the pump 20. If a pump test run is to be carried out, it is started in accordance with FIG. 1 by reducing the pressure detected by pressure switch 22. This pressure drop causes the pressure switch 22 to switch, thereby activating the pump control 21 and thus the pump 20. The pump 20 now starts to operate, thus pumping extinguishing fluid. Since the shut-off valve 51 to the pipe system is closed, the extinguishing fluid is conducted through the test line 3, where it is conducted via the fluid bypass line 4.

(15) In the specific embodiment of FIG. 1, the pump control 21 comprises a module which comprises the control unit 211. The control unit 211 is in communicative signal connection with the flow sensor 41, which is arranged at the test line 3. In the specific embodiment of FIG. 1, the flow sensor 41 and the control unit 211 form the control device for controlling the pump test run.

(16) The flow sensor 41 is configured to determine the flow volume per unit of time of the extinguishing fluid pumped by the pump 20 and thus to determine a parameter indicative of the cross-section of the fluid bypass line 4. The value of this parameter is then evaluated by the control unit 211. Based on this evaluation, the control unit 211 controls the pump test run of the pump 20. In particular, the control unit determines whether the pump test run should be aborted because of faults that could damage the pump, or whether the pump test run should not be started at all because of such faults, or whether the pump test run can be carried out as planned. In the latter case, the control unit deactivates the pump 20 once the pump test run has been successfully completed, i.e. once the operating parameters of the pump 20 have been reached.

(17) In the embodiment of FIG. 1, the pump test run is thus controlled by a control device comprising a control unit 211 and a flow sensor, where the parameter indicative of the cross-section of the fluid bypass line 4 is a flow parameter. The extinguishing fluid pumped by the pump 20 during the pump test run is discharged via the fluid bypass line 4, which in this manner prevents damage to the pump.

(18) The water extinguishing system 1 of FIG. 1 thus enables an automatic pump test run in which, even in the event of fire or energy failure, it can be ensured that, on the one hand, the water extinguishing system 1 provides sufficient extinguishing fluid for firefighting and that, on the other hand, the pump 20 is controlled in such a way that it remains active in the event of fire, even if the pump test run has been completed.

(19) FIG. 2 shows a water extinguishing system 1′ according to another preferred embodiment of the invention. The embodiment of FIG. 2 is in many respects similar to the embodiment of FIG. 1, and identical components are designated with identical reference numbers. The water extinguishing system 1′ also comprises a fluid supply tank 10, a fluid reservoir 11, a supply line 2 to a pipe system 500 with a shut-off valve 101, a pressure indicator 102, a pump 20, a non-return valve 50 and a second shut-off valve 51. In the embodiment of FIG. 2 the pump 20 also is controlled by the pump control 21 which comprises the control unit 211 and is connected to the pressure switch 22. The functionalities of these elements correspond to those of the embodiment of FIG. 1, which is why no further description is given here.

(20) The water extinguishing system 1′ of FIG. 2 is also configured for an automatic pump test run, which, as described in relation to FIG. 1, is started by the pump control 21 by means of the pressure switch 22. In the embodiment of FIG. 2, the water extinguishing system 1′ also comprises a test line 3 with an opening element 31 and a fluid bypass line 4. However, in the embodiment of FIG. 2, no flow sensor 41 is arranged at the test line. Instead, the water extinguishing system 1′ comprises a pressure difference sensor 42 which is configured to determine a first pressure value at a first position 43 at a first end of the fluid bypass line 4, more precisely where the fluid bypass line 4 branches off from the test line 3, and to determine a second pressure value at a second position 44 at a second end of the fluid bypass line 4, more precisely where the fluid bypass line 4 branches off to the test line 3. The pressure difference sensor 42 thus allows for the determination of the pressure difference between a position at the beginning of the fluid bypass line 4 and a position at the end of the fluid bypass line 4. This enables the measurement of a pressure loss of the extinguishing fluid along the fluid bypass line 4. This in turn allows for conclusions to be drawn about the properties of the cross-section of the fluid bypass line 4.

(21) For this purpose, the pressure difference is transmitted from the pressure difference sensor 42 to the control unit 211 in the pump control 21. The control unit 211 evaluates the determined pressure difference and thus determines whether the cross-section of the fluid bypass line is sufficient to reliably conduct the extinguishing fluid pumped by the pump 20 during the pump test run away from this pump and thus prevent damage to the pump 20.

(22) For this purpose, the control unit 211 is preferably configured to compare the value of the pressure difference with a previously defined threshold value. This threshold value may in particular indicate a maximum value for the pressure difference. If the value of the pressure difference exceeds this maximum value, this indicates that the cross-section of the fluid bypass line 4 is insufficient to prevent damage to the pump.

(23) Should the evaluation show that this is the case, the control unit 211 is configured to output a signal that aborts the pump test run. If the pump test run has not yet been started, this signal may also have the effect that the pump cannot be started at all.

(24) However, if the evaluation shows that the maximum value is not being exceeded, the pump test run can be carried out until the operating parameters of the pump 20 are reached, at which time it is terminated regularly by the control unit 211 of the control device.

(25) FIG. 3 shows a water extinguishing system 1″ according to another preferred embodiment. Here again, identical elements are designated with identical reference numbers. This means that the water extinguishing system 1″ also comprises a fluid supply tank 10, a fluid reservoir 11, a supply line 2 to a pipe system 500 with a first shut-off valve 101, a pressure indicator 102, a pump 20, a non-return valve 50 and a second shut-off valve 51. In the embodiment of FIG. 3 the pump 20 also is controlled by the pump control 21, which comprises the control unit 211 and is connected to the pressure switch 22.

(26) In contrast to the embodiments of FIGS. 1 and 2, however, in the water extinguishing system 1″ of FIG. 3, no measurement of the pressure or flow rate is carried out at the test line 3 or the fluid bypass line 4. Instead, the water extinguishing system 1″ comprises a temperature sensor 23, which is in communicative signal connection with the control unit 211 and together with it forms the control device for controlling the pump test run.

(27) In this case, the temperature sensor 23 is arranged at an outlet of the pump 20 and is configured to determine the temperature of the extinguishing fluid that has been pumped through the pump 20. This allows for the indirect determination of the temperature of the pump 20 and thus the determination whether or not the flow of the extinguishing fluid pumped by the pump 20 is sufficient to protect it from running dry and/or overheating—and thereby from damage. Although in the specific embodiment of FIG. 3 a temperature sensor 23 is used to detect possible damage to the pump 20, it should be understood that, alternatively or additionally, a noise sensor and/or a vibration sensor may be used to monitor the state of the pump. Such a noise sensor and/or a vibration sensor would also be arranged similar to the temperature sensor. Preferably a noise and/or vibration sensor may also be mounted directly at the pump casing.

(28) For this purpose, the temperature measured in this way is transmitted to the control unit 211. The control unit 211 is configured to compare the temperature with a temperature threshold value. If this temperature threshold value is exceeded, it means that the extinguishing fluid—and thus also the pump 20—has become too warm. If this is the case, the control unit 211 outputs a signal that aborts a pump test run that has already started or prevents a pump test run from being started. However, if the temperature is below the temperature threshold value, the control unit 211 allows the pump test run to continue until the operating parameters of the pump are reached and only then outputs a signal to terminate the pump test run.

(29) FIG. 4 shows a water extinguishing system 1′″ according to yet another preferred embodiment with a supply line 2, a test line 3, a fluid bypass line 4, a pump 20, a pipe system 500, a fluid supply tank 10 and a fluid reservoir 11, as described above. Again, identical elements are designated with identical reference numbers. This means that also in the water extinguishing system 1′″ a first shut-off valve 101, a pressure indicator 102, a non-return valve 50 and a second shut-off valve 51 are arranged along supply line 2 and the pump 20 is activated by a pump control 21 with a pressure switch 22.

(30) In contrast to the previous embodiments, however, in the embodiment of FIG. 4, the control device is no longer designed as a combination of a control unit 211 and a sensor, but rather as a switching arrangement 212, which is arranged at the fluid bypass line 4 and comprises a flow switch which is configured to switch from a deactivation position to an activation position at a specified flow volume of the extinguishing fluid through the fluid bypass line 4. If the pump is started with the pump control 21 by means of the pressure switch, as described in connection with FIG. 1, the extinguishing fluid flows through the fluid bypass line 4 with a specified amount of extinguishing fluid per unit of time. The pressure switch in the switching arrangement 212 is configured in such a way that it switches to the activation position if a specified amount of extinguishing fluid per unit of time is exceeded. In the activation position, the switching arrangement 212 causes the pump test run of the pump 20 to continue.

(31) However, if the flow volume per unit of time is too low, for example due to cavitation and/or deposits in the fluid bypass line 4, the switching arrangement 212 either does not switch to the activation position in the first place or switches back to the deactivation position, whereby the pump test run of the pump 20 is either not started at all or is aborted. In this way, the switching arrangement 212 prevents damage to the pump caused by an insufficient extinguishing fluid line.

(32) However, if the flow volume of the extinguishing fluid per unit of time is sufficient for the entire pump test run, no such switching of the switching arrangement 212 takes place. In this case, the pump 20 can reach its operating parameters and the pump test run is terminated regularly. The pump 20 then switches off and the flow volume through the fluid bypass line 4 per unit of time is reduced. This switches the switching arrangement 212, i.e. the flow switch changes from the activation position to the deactivation position, and thus also sends a deactivation signal for the pump test run.

(33) However, if a fire occurs during the pump test run, the flow volume per unit of time is not reduced by the continuously open fluid bypass line 4 as long as extinguishing fluid is still available, since the pump 20 continues to operate. In this case, the flow switch of the switching arrangement 212 remains in the activation position. This ensures that the pump is not switched off after the (supposed) completion of the pump test run, but continues to pump extinguishing fluid to fight the fire. This arrangement thus makes it possible to ensure operational readiness in the event of fire.

(34) FIG. 5 shows a water extinguishing system 1″″ according to yet another preferred embodiment. The arrangement of the water extinguishing system 1″ corresponds to that of the water extinguishing system 1′″ of FIG. 4 with regard to the sensors and its operating principle, with the difference that the fluid bypass line 4 in the water extinguishing system 1″″ of FIG. 5 branches off from the supply line 2 in order to conduct the extinguishing fluid around the shut-off element 31 of the test line 3 away from the pipe system 500. The arrangement of the fluid bypass line 4 changed in this way does not affect the pump test run described above in connection with FIG. 4. It should be understood in this regard that the water extinguishing systems 1, 1′ and 1″ of FIGS. 1, 2 and 3 may also be equipped with a design of the fluid bypass line 4 according to FIG. 5 without affecting the general operating principle of the water extinguishing systems 1, 1′ and 1″ and the corresponding pump test runs.

(35) A combination of the sensor arrangements and/or designs of the fluid bypass line 4 and/or the test line 3 according to the exemplary embodiments of FIGS. 1 to 5 is also conceivable. For example, a combination of a temperature sensor in the vicinity of the pump 20 with a pressure difference sensor at the fluid bypass line 4 may be used to ensure improved monitoring of the pump test run. This combination may also be combined with a flow sensor at the fluid bypass line 4 and/or a vibration sensor at the pump 20 and/or a noise sensor at or in the vicinity of the pump 20 to improve monitoring even further. Other combinations which are immediately apparent to the person skilled in the art after studying the above description are also provided according to the invention.

LIST OF UTILIZED REFERENCE NUMBERS

(36) 1, 1′, 1″, 1′″, 1″″ water extinguishing system 10 fluid supply tank 11 fluid reservoir 101 first shut-off valve 102 pressure indicator 2 supply line 20 pump 21 pump control 22 pressure switch for pump control 23 temperature sensor 211 control unit 212 switching arrangement 3 test line 31 opening element 4 fluid bypass line 41 flow sensor 42 differential pressure sensor 43 first position 44 second position 50 non-return valve 51 second shut-off valve 500 pipe system 501 sprinkler