Monitoring device and monitoring method for switchgear with a valve device and use of the valve device

Abstract

Monitoring arrangement (42) comprising a monitoring device (43) comprising a multi-way valve device (44) and a monitoring unit (63) for monitoring at least one gas parameter of a harmful gas in an electrical installation (40), and a test device (19) for checking at least one function of the monitoring unit (43);wherein the multi-way valve device (44) is configured for connecting the monitoring device (63) to the electrical system (40) containing the pollutant gas and to be monitored with respect to the gas parameter, and comprises a first valve path (64) configured as a gas connection (13) for connecting the multi-way valve device (44) to the system (40), a second valve path (65) configured for gas transfer to the monitoring device (63), a third valve path (66) configured for gas transfer to the test device (19) for checking at least one function of the monitoring device (63), and an automatic switching device (56) for selectively automatically connecting the second valve path (65) to the first valve path (64) or the third valve path (66), wherein the test device (10) can be connected to or is connected to the third valve path (66) configured as a third gas connection (15).

Description

[0001] The invention relates to a monitoring arrangement comprising a monitoring device and a valve device for connecting a density monitor or the like to a system to be monitored with respect to gas density or the like. The invention also relates to an electrical system equipped with such a monitoring arrangement. Furthermore, the invention relates to a monitoring method and the use of a valve device.

[0002] GB 347 172 A concerns the connection of a pressure gauge to a pneumatic tire using a multi-way valve assembly. US 2005 / 0072479 A1 concerns a multi-way valve assembly, for example, for irrigation systems.

[0003] From DE 10 2010 055 249 A1 a density monitor for monitoring a gas density in a measuring volume is known, comprising a membrane which is connected to the measuring volume in such a way that it moves when a gas density in the measuring volume changes, and a membrane movement detection device connected to the membrane for converting a membrane movement into an electrical signal.

[0004] For the technological background of density monitors, particular reference is made to JPS5578231A, US 1527597 A, US 3431785 A, US 6125692 A, US 2662394 A, US 5421190 A and DE 10232823 A.

[0005] Density monitors are measuring devices for monitoring the gas density of a gas under observation. As known from DE 10 2010 055 249 A1, density monitors are used in particular for monitoring the density of gases, such as SF6, acting as insulators in gas-insulated high- and medium-voltage systems or devices, such as high-voltage switchgear, transformers, pipelines, switching devices and transformers.

[0006] For example, density monitors based on electronic measuring principles are known from DE 10232823 A1, which are equipped with an electronic density sensor as a measuring transmitter, which has a quartz oscillator arranged in the gas and provides a frequency signal proportional to the density of the gas as the measured value, wherein the frequency signal is supplied to an electronic evaluation unit.

[0007] In contrast, density monitors based on mechanical measuring principles have become established on the market. Due to their mechanical design, these monitors are highly reliable and require little maintenance, even over very long periods. In the simplest and most common configuration, a diaphragm operating via a reference volume is connected to the measuring volume. A change in gas density causes the diaphragm to actuate a switch. For example, in the density monitor known from DE 10 2010 055 249 A1, a diaphragm of a metal bellows is connected to a switch, so that a diaphragm movement beyond a minimum distance triggers a switching operation.

[0008] From DE 27 51 206 A1 a density monitor with a switching device comprising a mercury switch is known.

[0009] From DE 27 44 549 A1, a device for monitoring the density of a gas is known, comprising a manometer with a pointer and a Bourdon tube as an expansion element, and a compensation element between the pointer and the expansion element. A segment lever is provided for driving the pointer.

[0010] From DD 282 076 A5, a density monitor for monitoring the density of a gas in a hermetically sealed container is known, enabling the longest possible maintenance-free operating time even with minor leaks in the container. Two metal bellows are provided for this purpose.

[0011] A plunger is located between the metal bellows, which, via a drive lever and a switching lever, actuates a double-pole switch. Closing the first contact triggers a warning signal; if the pressure continues to drop, a second contact closes, actuating a solenoid valve to refill the container with gas until the contacts are opened again.

[0012] Density monitors are used primarily to monitor gas storage areas filled with gases that pose a risk to the environment, especially for leaks. Therefore, these monitors must operate very reliably and provide consistent warning signals – even over extended periods – when concerning changes in gas density occur.

[0013] The object of the invention is to provide a simple way to further improve the reliability of monitoring a gas space filled with a harmful gas.

[0014] This problem is solved by a monitoring arrangement according to claim 1. Advantageous embodiments are the subject of the dependent claims. The monitoring arrangement comprises a monitoring device, such as a density monitor. A combination of the monitoring arrangement with a system to be monitored, a monitoring method that can be carried out therewith, and the use of a multi-way valve device for such monitoring are described in the dependent claims.

[0015] According to a first aspect, the invention relates to a monitoring arrangement comprising a monitoring device and a testing device.The monitoring device comprises the monitoring unit and a multi-way valve device for connecting the monitoring unit for monitoring at least one gas parameter to an electrical system containing a harmful gas and to be monitored with respect to the gas parameter, wherein the multi-way valve device has a first valve path designed as a gas connection for connecting the valve device to the system, a second valve path designed for gas transfer to the monitoring unit, a third valve path designed for gas transfer to a test device for verifying at least one function of the monitoring unit, and an automatic switching device for selectively connecting the second valve path to the first valve path or the third valve path.

[0016] The monitoring device preferably includes a density monitor and / or a pressure sensor. In a preferred embodiment, a density monitor is provided which optionally or in combination detects both the gas density and the pressure of the gas to be monitored.

[0017] It is preferred that the second valve path includes a check valve arrangement which is biased into a closed position to close the second valve path and which can be moved into an open position by connecting the monitoring device.

[0018] It is preferred that the check valve arrangement has a check valve opener pre-tensioned in its closed position, which is detected by a connection element of the monitoring device when the monitoring device is connected, in order to move the opener into its open position against its pre-tension by connecting.

[0019] It is preferred that the switching device has a valve plunger which is biased into a first switching position in which the third gas connection is closed and the first gas connection is connected to the second valve path and can be moved into a second switching position in which the first gas connection is closed and the second valve path is connected to the third gas connection by connecting the test device to the third gas connection.

[0020] It is preferred that the valve tappet includes a projection or pin which, when the test device is connected, is engaged by a connecting element of the test device and is pressed from the first switching position to the second switching position against its preload.

[0021] It is preferred that at least one sensor device for detecting at least one parameter selected from the group of parameters including temperature, density, pressure, humidity, type of gas and presence of a decomposition product is in fluid communication with the first gas connection and / or the second valve path.

[0022] It is preferred that the first valve path be designed as the first gas connection.

[0023] It is preferred that the second valve path is designed as a second gas connection for connecting the monitoring device to the multi-way valve device.

[0024] It is preferred that the third valve path be designed as a third gas connection for connecting the test device.

[0025] According to the invention, the monitoring device comprises the multi-way valve device and the monitoring device for monitoring at least one gas parameter of a pollutant gas in an electrical system.

[0026] It is preferred that the monitoring device and the multi-way valve device are designed separately, with the monitoring device being connectable to the second valve path.

[0027] In another embodiment, it is preferred that the monitoring device and the multi-way valve device are integrated in a common unit or a common housing.

[0028] It is preferred that the monitoring device includes at least one density monitor and / or a sensor device.

[0029] The monitoring arrangement according to the invention comprises such a monitoring device according to one of the preceding embodiments and the test device for checking at least one function of the monitoring device.

[0030] According to the invention, it is further provided that the test device can be connected to or is connected to the third valve path, which is designed as a third gas connection.

[0031] According to another aspect, the invention provides an electrical system comprising a gas chamber filled with a harmful gas and a monitoring arrangement according to one of the preceding embodiments.

[0032] According to a further aspect, the invention provides a monitoring method for monitoring at least one gas parameter of a pollutant gas in an electrical system by means of a monitoring device comprising a multi-way valve device and a monitoring unit for monitoring the at least one gas parameter of a pollutant gas in an electrical system, comprising the steps: Connecting the monitoring device to the electrical system containing the pollutant gas and to be monitored with regard to the gas parameter by means of the multi-way valve device, wherein the valve device is connected to the system via a first valve path as a gas connection and a gas transfer to the monitoring device takes place via a second valve path of the valve device, and wherein a third valve path of the valve device is used for a gas transfer to a test device for checking at least one function of the monitoring device and the test device is connected to the third valve path designed as a third gas connection, and Optional automatic connection of the second valve path to the first valve path or the third valve path by means of an automatic switching device of the valve assembly.

[0033] According to a further aspect, the invention relates to the use of a multi-way valve device for connecting a monitoring device for monitoring at least one gas parameter to an electrical system containing a harmful gas and to be monitored with respect to the gas parameter, wherein the multi-way valve device comprises a first valve path which is used as a gas connection for connecting the valve device to the system, a second valve path which is used for the gas transfer to the monitoring device, a third valve path which is used for a gas transfer to a test device for checking at least one function of the monitoring device, and an automatic switching device which is used for selectively automatically connecting the second valve path to the first valve path or the third valve path.

[0034] In one embodiment of the monitoring arrangement according to the invention, a multi-way valve device is provided for connecting a monitoring device for monitoring at least one gas parameter to a system containing a harmful gas and to be monitored with respect to the gas parameter, wherein the multi-way valve device comprises a first gas connection for connecting the valve device to the system, a second gas connection for connecting to the monitoring device, a third gas connection for connecting a test device for checking the function of the monitoring device, and a switching device for automatically and selectively connecting the second gas connection to the first or the third gas connection.

[0035] In a preferred embodiment, the invention relates to a monitoring arrangement with a multi-way valve device for connecting a density monitor to a system to be monitored with regard to gas density, comprising a first gas connection for connecting the valve device to the system, a second gas connection for connecting to the density monitor, a third gas connection for connecting a test device for checking the function of the density monitor and a switching device for automatically and selectively connecting the second gas connection to the first or the third gas connection.

[0036] It is preferred that the second gas connection includes a check valve arrangement which is biased into a closed position to shut off the second gas connection and which can be moved into an open position by connecting the monitoring device, in particular the density monitor.

[0037] It is preferred that the switching device has a valve device, in particular a valve tappet, which is biased into a first switching position in which the third gas connection is closed and the first gas connection is connected to the second gas connection and can be moved into a second switching position in which the first gas connection is closed and the second gas connection is connected to the third gas connection by connecting the test device to the third gas connection.

[0038] Preferably, the check valve arrangement comprises a check valve opener pre-tensioned in its closed position, which is detected by a connection element of the monitoring device when the monitoring device is connected, in order to move the opener into its open position against its pre-tension by connecting it.

[0039] Preferably, the valve assembly, in particular the valve plunger, comprises a projection or pin which, when the test device is connected, is engaged by a connecting element of the test device and is pressed against its preload from the first switching position to the second switching position.

[0040] It is preferred that at least one sensor device for detecting at least one parameter selected from the group of parameters including temperature, humidity, type of gas and presence of a decomposition product is in fluid communication with the first gas connection and / or the second gas connection.

[0041] In particular, the invention provides a monitoring arrangement, in particular a density monitoring arrangement, comprising a multi-way valve device according to one of the preceding embodiments and a monitoring device, in particular a density monitoring device, with a gas parameter sensor, in particular a density monitor, wherein the monitoring device can be connected to the second gas connection.

[0042] A preferred embodiment of the monitoring arrangement comprises a test device to be connected to the third gas connection for checking a switching point and / or a function of the monitoring device, in particular the density monitor.

[0043] According to another aspect, the invention provides an electrical system, in particular a switchgear system, comprising a gas space filled with a gas whose density is to be monitored and a multi-way valve device according to one of the previously described embodiments for connecting a density monitor and / or a monitoring device to the gas space.

[0044] The invention provides, in particular, a simple way to periodically check the function of gas monitoring devices. Especially in the case of density monitors mounted on electrical systems such as switchgear, it is desirable that the status or switching points of the density monitor can be checked at any time without disassembling the system. The same applies to density sensors or, more generally, sensors used for monitoring the condition of systems (e.g., humidity sensors, sensors that measure the chemical decomposition of the insulating gas SF6, e.g., SF4, WF6, SOF4, SO2F2, SOF2, SO2, and / or HF; but also detect oils and dust).

[0045] According to a preferred embodiment of the invention, a modular 3-way valve is proposed for this purpose, which preferably adapts to tank flanges from different manufacturers.

[0046] Previously, a check valve was always used between the density monitor and the tank, but this is no longer necessary when using the three-way valve. An advantageous embodiment provides for the integration of other sensors in the flange connection, ideally measuring directly in the gas space to ensure more accurate readings. Preferred embodiments suggest a humidity sensor, a gas quality sensor, and / or a temperature sensor. A simple density sensor, as well as a mixed-gas density sensor for binary mixtures (pressure / temperature / density), could also benefit from this placement.

[0047] A preferred embodiment of the invention relates to the use of an automatic 3-way valve for SF6 density monitors.

[0048] In a preferred embodiment of the invention, a modular 3-way valve is provided for use on electrical switchgear, which (1) allows functional testing of the sensor / monitor in the installed state and / or (2) additional sensors (e.g. humidity, concentration, arc flash monitoring, decomposition products or the like) which can preferably also be checked.

[0049] A preferred use of the invention or its embodiments relates to the case of a density monitor mounted on an electrical switchgear. An advantage of preferred embodiments is that the state or switching points of the monitor can be checked at any time without disassembling the switchgear. The same applies to density sensors or, more generally, sensors used for monitoring the condition of equipment. Examples include humidity sensors, sensors that measure the chemical decomposition of the insulating gas SF6 (e.g., SF4, WF6, SOF4, SO2F2, SOF2, SO2, and / or HF), but also oils and dust. Although the embodiments of the invention are described using the example of a density monitor particularly suitable for SF6, other gases, especially insulating gases, can also be monitored and the monitoring device checked in other applications.

[0050] One design proposes an automatic 3-way valve, which is integrated directly into the density monitor, to allow for checking the density monitor without disassembly.

[0051] In one design, a separate automatic 3-way valve is mounted on the switchgear, and the density monitor is then attached to this valve. With the automatic 3-way valve integrated directly into the density monitor, this additional component can be omitted.

[0052] A particularly preferred embodiment of the monitoring device relates to a density monitor or gas parameter sensor (pressure, temperature, humidity,...) with an integrated automatic 3-way valve for use on electrical switchgear, which allows functional testing of the sensor / monitor in the installed state.

[0053] Two exemplary embodiments are explained in more detail below with reference to the accompanying drawings. These show: Fig. 1 A partially cutaway representation of a first embodiment of a monitoring arrangement for monitoring the gas space of a high-voltage or medium-voltage electrical system, such as, in particular, a switchgear system, wherein the gas space is filled with an insulating gas or protective gas, wherein the monitoring arrangement comprises a monitoring device or a monitoring instrument, in particular a density monitor, for monitoring at least one gas parameter of the insulating gas or protective gas and a multi-way valve device for connecting the monitoring device to the gas space and for optionally connecting the monitoring device to a test instrument. Fig. 2 An enlarged detail of the multi-way valve device in the area of ​​a gas connection for connecting the test device. Fig. 3 An enlarged detail of the multi-way valve device in the area of ​​a gas connection for connecting the monitoring device. Fig. 4 A schematic representation of the switchgear with the monitoring device. Fig. 5 A representation of a second embodiment of a monitoring device for monitoring the gas space of a high-voltage or medium-voltage electrical system, with an integrated multi-way valve device. Fig. 6 An enlarged detail of the multi-way valve device in the area of ​​a valve path for connecting a test device. Fig. 7 a first side view of the monitoring device of Fig. 5. Fig. 8 a front view of the monitoring device of Fig. 5. Fig. 9 another side view of the monitoring device of Fig. 5. Fig. 10 a perspective view of the monitoring device of Fig. 5.

[0054] In the following, exemplary embodiments of an electrical system 40 with a gas chamber 17 filled with an insulating gas and a monitoring arrangement 42 are explained in more detail with reference to the figures. First, the following will be discussed: Fig. 4 Reference is made to a schematic overview.

[0055] The electrical installation 40 is, in particular, a gas-insulated medium-voltage or high-voltage installation, such as a switchgear, a voltage transformer, a high- or medium-voltage pipeline, a switching device, or a transformer. The conductors carrying the high or medium voltage are housed within a closed gas space 17 containing an insulating gas, such as, in particular, SF6, or an insulating gas mixture, e.g., with SF6 and other gas components.

[0056] A monitoring arrangement 42 is connected to the gas space 17 for monitoring the gas space 17, in particular for monitoring the gas density and / or other parameters, such as temperature, humidity, gas composition, pressure, etc. The monitoring arrangement 42 has a monitoring device 43 for this purpose. The monitoring device 43 has a monitoring unit 63 and a multi-way valve 44 for connecting the monitoring unit 63 to the gas space 17.

[0057] During the Fig. In the first embodiment of the monitoring device 43 shown in Figures 1 to 3, the monitoring unit 63 and the multi-way valve device 44 are designed separately. In the embodiment shown in the Fig. In the second embodiment of the monitoring device 43 shown in Figures 5 to 10, the multi-way valve device 44 and the monitoring device 63 are integrated in one unit.

[0058] In both embodiments, the multi-way valve device 44 is designed to connect the monitoring device 63, which is configured to monitor at least one gas parameter, to an electrical system 40 containing a harmful gas and to be monitored with respect to that gas parameter. The multi-way valve device 44 comprises a first valve path 64 for connecting the valve device 44 to the system 40, a second valve path 65 configured for gas transfer to the monitoring device 43, a third valve path 66 configured for gas transfer to a test device 19 for verifying at least one function of the monitoring device 63, and an automatic switching device 56 for selectively and automatically connecting the second valve path 65 to either the first valve path 64 or the third valve path 66.

[0059] The following will be based on the Fig. Sections 1 to 4 explain the first embodiment in more detail.

[0060] The multi-way valve device 44 in the first embodiment has a first gas connection 13 for connecting the gas chamber 17, a second gas connection 14 for connecting the monitoring device 43, and a third gas connection 15 for connecting a test system 46, by means of which at least one function of the monitoring device 43 can be tested. The first gas connection 13 is formed on the first valve path 64, the second gas connection 14 is formed on the second valve path 65, and the third gas connection 15 is formed on the third valve path 66. The gas connections 13, 14, 15 can, for example, be threaded for connecting corresponding gas lines; of course, other gas connection configurations are also conceivable.

[0061] The multi-way valve device 44 is designed for automatically switching and connecting the gas connections 13, 14, 15. Preferably, the multi-way valve device 44 is designed such that when only the gas chamber 17 is connected to the first gas connection 13 and no appliance is connected to the other gas connections 14, 15, the other gas connections 14 and 15 are closed.

[0062] Preferably, the multi-way valve device 44 is designed such that when the monitoring device 43 is connected to the second gas connection 14, but the third gas connection 15 remains unused, the first gas connection is in fluid communication with the second gas connection, so that the gas space 17 is in fluid communication with the monitoring device 43, so that the gas space 17 can be monitored with the monitoring device 43.

[0063] Preferably, the multi-way valve device 44 is further designed such that when the test system 46 is connected to the third gas connection 15, an automatic switching of the fluid connection between the gas connections 13, 14, 15 takes place such that the first gas connection 13 is blocked and the second gas connection 14 is connected to the third gas connection 15, so that the monitoring device 42 connected to the second gas connection 14 can be checked for at least one function by the test system 46.

[0064] For example, the test system 46 can be formed by a mobile test device 19, which can be connected to the respective third gas connection as needed to test several such monitoring devices 43, in order to immediately carry out a test of the monitoring device 43 in its ongoing operation without dismantling or other effort and without impairing the tightness or gas safety.

[0065] In Fig. 1 shows the overall structure, Fig. Figure 2 shows the construction of the multi-way valve device 44 in the area of ​​the third gas connection 15, and Fig. Figure 3 shows the construction of the multi-way valve device 44 in the area of ​​the second gas connection 14.

[0066] As from Fig. As can be seen in Figure 1, the multi-way valve device 44 has a valve housing 1 in which the gas connections 13, 14, 15, e.g. with corresponding connection threads (not shown) are inserted.

[0067] The gas chamber 17 can be formed by a tank from a different manufacturer. The first gas connection 13 can be connected to different tank nozzles, e.g., using different adapters (not shown).

[0068] In the area of ​​the third gas connection 15, a valve plunger 2 is provided as an opener and a closer. The valve plunger 2 can be moved between a closed position and an open position by means of a sensor that detects the connection of a test system 46.

[0069] For this purpose, the valve tappet 2 has in particular a cylinder or pin 3 for an automatic closing and opening function such that the cylinder or pin 3 projects to the end area of ​​the third gas connection 15 and is pressed into the valve housing 1 when the test system 46 is connected, in order to move the valve tappet 2 from its closed position to its open position.

[0070] As can be seen in particular from Fig. As 2 results, the valve tappet 2 is slidably housed in a fluid channel chamber 48. At both longitudinal ends of the fluid channel chamber 48, this chamber has a sealing cone 16, 16'.

[0071] At the in Fig. At the first end shown above, which faces the connection for the test system 46, a first passage 50 to the test system 46 is provided, which is closed by means of a first seal 4 when the valve tappet 2 moves against the first sealing cone 16 arranged here.

[0072] At the in Fig. At the second end shown below, a second passage 52 to the first gas connection 13 is provided, which can be closed by means of a second seal 5 when the valve tappet 2 is moved against the second sealing cone 16'. A gap is left between the valve tappet 2 and the wall of the fluid channel chamber 48. A passage 54 opens laterally into the fluid channel chamber 48 thus left open, leading to the second gas connection 14, which is shown more closely in Fig. 3 is shown.

[0073] The valve tappet 2 is held in its position by a compression spring 6. Fig. 1. The closed position shown is pre-tensioned. Fig. Figure 2 shows the opening position of the valve tappet 2 with the test system 46 connected.

[0074] In the closed position of the valve plunger 2, the first gas connection 13 is connected to the second gas connection 14 via the second passage 52 at the second end of the fluid channel chamber 48, the fluid channel chamber 48 and the lateral passage 54. The valve plunger 2 also fulfills a check valve function by being forced into its closed position by overpressure at the first gas connection 13.

[0075] In the open position of the valve tappet 2, the second passage 52 is closed by the second seal 5 being placed against the second sealing cone 16' and the first passage 54 is open, so that the third gas connection 15 is connected to the second gas connection 14 via the first passage 54, the fluid channel space 48 and the passage 54.

[0076] Thus, the valve tappet 2 forms a switching device 56, with which, when the test system 46 is connected, an automatic switching between a first switching position - the closed position - and a second switching position - the open position - takes place, in order to decouple the monitoring device for checking from the gas space 17 and to couple it to a test device 19 during operation.

[0077] The second gas connection 14 is equipped with a non-return valve assembly 58, which is described in more detail in Fig. Figure 3 shows the check valve arrangement 58 having a closed position in which the second gas connection 14 is closed, and an open position in which the second gas connection 14 is open, and an opening mechanism 60 which detects a connection of the monitoring device 43 to the second gas connection 14 and automatically moves the check valve arrangement 58 from the closed position to the open position upon connection.

[0078] The check valve assembly 58 is designed such that it is forced into its closed position by overpressure inside the valve housing 1, and in particular by overpressure on the side of the first gas connection 13. Preferably, the check valve assembly 58 is also biased into its closed position, e.g. by a compression spring 10.

[0079] As from Fig. As can be seen in Figure 3, the check valve assembly 58, in a preferred embodiment, has an opener 7 slidably arranged in a channel opening 62 for opening and closing the check valve at the connection for the monitoring device 42. Furthermore, a retaining ring 8 is inserted in the channel opening 62 to secure the check valve assembly at the connection for the monitoring device 42. The check valve assembly 58 also has a sleeve 9 with a sealing cone 16 against which a seal 11 attached to the opener 7 can seal. The sleeve 9 is sealed externally against the wall of the channel opening 62 by a seal 12. The opener 7 is biased into its closed position against the sealing cone 16 of the sleeve 9 by the compression spring 10.

[0080] As in Fig. As shown in Figure 1, the multi-way valve device 44, in a preferred embodiment, has a sensor installation 18. Fig. Figure 1 shows two possible connections for the sensor assembly 18. In a first version, the sensor assembly 18 is connected to the first gas connection 13 and is thus permanently and / or directly connected to the gas space 17. In a second embodiment, the sensor assembly 18 is connected to the second gas connection 14. The first embodiment has the advantage of the direct connection. This allows for more immediate measurement of temperature, humidity, and gas composition, and also enables the detection of an electric arc. The second embodiment has the advantage that the sensor assembly 18 can be tested, for example, by the test system 46 without being removed. The sensor assembly 18 can thus be an embodiment of the monitoring device 43 or can be part of the monitoring device 43.

[0081] In a preferred embodiment, the sensor assembly 18 has at least one, several or all of the following sensors: humidity sensor 26, temperature sensor 27, decomposition product sensor 28, arc counter 29 or an arc detection system and pressure sensor.

[0082] As in Fig. As indicated in Figure 1, the monitoring device 43 in a preferred embodiment has at least one density monitor 20. The density monitor 20 is designed in particular as described and shown in WO 2015 / 101442 A1 and DE 10 2013 115 009 A1, to which reference is expressly made for further details.

[0083] In a preferred embodiment, the test system 46 comprises at least one test device 19 for testing a switching point of the density monitor 20 and / or for testing a function of the density monitor 20 and / or of a sensor 26, 27, 28.

[0084] In a preferred embodiment, the test device 19 includes a reference sensor and / or a reference density monitor 21. This allows a signal 30 supplied to the monitoring device 43, for example via a line, to be compared with a reference value in order to verify its function.

[0085] In a preferred embodiment, the test device 19 comprises at least one, several, or all of the following units: a pump 20, a display 23, e.g., a screen, an electronic control 24, a user interface 25, in particular in the form of a GUI, and / or a memory and / or microcontroller 31.

[0086] The function of the monitoring arrangement 42 described here is explained in more detail below. The figures show, in particular, a valve which has at least three ports 13; 14; 15.

[0087] The first gas connection 13 is permanently connected to the gas room 17, in particular to a switchgear. In this state, the second gas connection 14 and the third gas connection 15 are closed.

[0088] By connecting a density monitor 20 to the second gas connection 14, the opener 7 of the check valve is opened and the gas passage from the gas space 17 to the density monitor 20 is enabled.

[0089] During operation, a test device 19 can be connected via the third gas connection 15, which is provided for a test system 46. Connecting the test device 19 automatically disconnects the gas chamber 17 of the switchgear or similar device from the pressure monitor 20 and the test device 19 by means of the valve plunger 2. When the switchgear is disconnected, the gas flow is only ensured between the pressure monitor 20 (second gas connection 14) and the test device 19 (third gas connection 15). The test device 19 uses the residual gas trapped in the gas chamber 17 of the switchgear to test the pressure monitor 20. After testing the pressure monitor 20, the residual gas is pumped back through the test device 19. When the test device 19 is disconnected, the multi-way valve 44 automatically switches back to its original position by means of the valve plunger 2.

[0090] The following will be based on the Fig. 5 to 10 explains in more detail the second embodiment of the monitoring device 43.

[0091] While in a possible use of the first embodiment a separate 3-way valve is to be mounted on a switchgear and a monitoring device 63, such as a density monitor 20 in particular, is to be mounted on this 3-way valve, in a preferred use of the second embodiment an automatic 3-way valve is to be integrated directly together with the monitoring device 63 in a single unit. For example, a multi-way valve device 44 is integrated directly into a density monitor 20.

[0092] In the following description of the second embodiment, the same reference numerals are used for corresponding parts as in the first embodiment, and further details and functions of these parts are referred to the above description of the first embodiment.

[0093] As from the Fig. As can be seen from Figures 5, 7 to 10, the second embodiment of the monitoring device 43 has a multi-part housing 69 which contains the monitoring device 63 and the multi-way valve device 44.

[0094] In the illustrated embodiment, the monitoring device 63 includes the density monitor 20 in a density monitor housing part 70. The monitoring device 63 is connected to the gas space 17 to be monitored via a tubular connection housing part 71. The multi-way valve device 44, which may, for example, include an automatic 3-way valve, is housed in this connection housing part 71.

[0095] The first valve path 64 has the first gas connection 13 for connecting the gas chamber 17. The second valve path 65 is housed in the overall casing 69 and serves to transfer the gas to the monitoring device 63 integrated in the overall casing 69. The second valve path is, for example, configured as a gas transfer from the connection housing part 71 to the leak detector housing part 70. In a preferred embodiment, the third valve path 66 has the third gas connection 15 for connecting the test device 19. In the illustrated embodiment, a protective cap 67, for example, designed as a threaded cover, may be included. The protective cap 67 can be secured to one of the casing parts 70, 71 of the overall casing 69 by a protective cap retainer 68.

[0096] The Fig. 5 and Fig. Figure 6 shows a section through the multi-way valve device 44. The connection housing part 71 serves as the valve housing, i.e., it has a valve housing area 72 in which the movable valve plunger 2 is housed. As in the first embodiment, the pin 3 is provided for the automatic closing and opening function, the seal 4 for the valve test port, the seal 5 for the valve to the gas chamber 17 or to a switching system, and the compression spring 6 for the valve to the test port.

[0097] Fig. Figure 6 shows the valve tappet 2 in its normal position, without the test device 19 being connected to the third gas connection (test connection or service connection) 15. The compression spring 6 pushes the valve tappet 2 in the Fig. 6 to the left, so that the seal 4 closes the third valve path 66, which here leads to the third gas connection 15. There is a fluid connection between the first and second valve paths 64, 65, and thus the monitoring device 63 – in particular the density monitor 20 – and the first gas connection 13 are in fluid contact. For example, the density monitor can monitor the gas space 17 connected to the first gas connection 13.

[0098] When the test device 19 is connected, the valve tappet 2 is moved via pin 3. Fig. 6 is shifted to the right, thereby opening the second valve passage 65 and closing the first valve passage 64 by means of the seal 5. Thus, the monitoring device 63 is in fluid communication with the test device 19, and the connection to the monitored gas chamber 17 is severed.

[0099] The Fig. Figures 5 to 10 show in particular a density monitor 20 with an integrated maintenance connection (third gas connection 15). The first gas connection 13 is permanently connected to the gas chamber 17 of the switchgear.

[0100] In the normal operating state shown, the third gas connection 15 is closed, and the flow from the gas space 17 to the density monitor 20 is ensured.

[0101] In the plant, a test device 19 can be connected via the third gas connection 15 (gas connection test system).

[0102] By connecting a test device 19 to the third gas connection 15, the valve plunger 2 is pushed in, and this movement opens the passage from the test unit 19 to the pressure monitor 20. Simultaneously, the passage from the gas chamber 17 to the pressure monitor 20 is closed. The test device 19 uses the residual gas trapped in the switchgear to test the pressure monitor 20. After the pressure monitor 20 has been tested, the residual gas is pumped back through the test device 19. When the test unit (e.g., test device 19) is disconnected, the valve plunger 2 automatically switches back.

[0103] During the Fig. The embodiment shown in Figures 5 to 10 is therefore a multi-way valve device 44, which is directly integrated into the density monitor 20, and which allows the density monitor 20 to be checked without disassembly.

[0104] As in Fig. As indicated in Figure 5, a monitoring device 43 comprises a monitoring unit 63 and a multi-way valve device 44. The monitoring unit 63 has at least one leak detector 20, which has at least one integrated third valve path 66. The first valve path 64 is permanently connected to the gas chamber of the switchgear 17. In this state, the third valve path 66 is closed, and flow from the gas chamber 17 to the leak detector 20 is ensured. The design allows a test device 19 to be connected via the third valve path 66 during operation.

[0105] Fig. Figure 6 shows an excerpt from Fig. Figure 5 represents a detail of the multi-way valve device 44. By connecting the test device 19 to the third valve path 66, the valve plunger 2 is pushed in against the spring force of the compression spring 6, thus opening the passage from the test unit 19 to the sealing monitor 20, whereby the valve plunger 2 with the seal 5 moves against the sealing cone 16'. When the test unit is disconnected, the valve plunger 2 automatically switches back by moving against the first sealing cone 16.

[0106] Fig. Figures 7 to 10 show further illustrations of the monitoring device 43. In these embodiments, the third valve path 66 is provided with the protective cap 67 with protective cap locking device 68 to prevent contamination of the third valve path 66. Reference symbol list: 1 Valve housing 2 valve tappets: opener / closer 3 cylinder pins for automatic locking / unlocking function 4 Seal Valve Test Port 5 Seal Valve Switchgear 6 Compression spring for valve test port / switchgear 7 opener check valve, pressure monitor connection 8. Retaining ring, check valve assembly, leak detector connection 9 Sleeve Check valve Pressure monitor connection 10 Compression spring for check valve, leak detector connection 11 Seal for check valve, pressure monitor connection 12 Seal Check Valve Assembly 13 First gas connection (especially switchgear) 14 second gas connection (monitoring device, in particular density monitor) 15 Third gas connection (testing facility) 16 first sealing cone 16' second sealing cone 17 Gas space of the switchgear to be monitored 18 Sensor installation 19 Test device for switching point or function testing 20 density monitors 21 Reference sensor or reference density monitor 22 Pump 23 Display 24 Electronic control 25 GUI = User Interface 26 humidity sensor 27 Temperature sensor 28 Decomposition product sensor 29 arc counters, arc detection 30 Signal from the built-in density monitor to the test device 31 Memory & Microcontrollers 40 electrical system 42 Monitoring order 43 Monitoring device 44 Multi-way valve device 46 Test facility 48 Fluid channel space 50 first passage 52 second passage 54 Passage 56 Switching device 58 Check valve arrangement 60 Opening mechanism 62 Channel opening 63 Monitoring device 64 first valve stroke 65 second valve path 66 third valve path 67 Protective cap 68 Protective cap lock 69 Total housing 70 Density monitor housing part 71 Connection housing part 72 Valve housing area

Claims

[1] Monitoring arrangement (42) comprising a monitoring device (43) which comprises a multi-way valve device (44) and a monitoring device (63) for monitoring at least one gas parameter of a harmful gas in an electrical system (40), and a testing device (19) for checking at least one function of the monitoring device (43);wherein the multi-way valve device (44) is designed to connect the monitoring device (63) to the electrical system (40) containing the harmful gas and to be monitored with regard to the gas parameter, and comprises a first valve path (64) designed as a gas connection (13) for connecting the multi-way valve device (44) to the system (40), a second valve path (65) designed for gas transfer to the monitoring device (63), a third valve path (66) designed for gas transfer to the testing device (19) for testing at least one function of the monitoring device (63), and an automatic switching device (56) for selectively automatically connecting the second valve path (65) to the first valve path (64) or the third valve path (66), wherein the testing device (10) is connectable or connected to the third valve path (66) designed as a third gas connection (15); [2] Monitoring arrangement (42) according to claim 1, characterized by that the second valve path (65) contains a check valve arrangement (58) which is prestressed into a closed position to close the second valve path (65) and which can be transferred into the open position by connecting the monitoring device (63). [3] Monitoring arrangement (42) according to claim 2, characterized by that the check valve arrangement (58) has a check valve opener (7) which is prestressed in its closed position and which, when the monitoring device (63) is connected, is detected by a connecting element of the monitoring device (63) in order to move the opener (7) into its open position against its prestress by the connection. [4] Monitoring arrangement (42) according to one of the preceding claims, characterized byin that the switching device (56) has a valve tappet (2) which is pretensioned into a first switching position in which the third gas connection (15) is closed and the first gas connection (13) is connected to the second valve path (65), and which can be transferred into a second switching position by connecting the testing device (19) to the third gas connection (15), in which the first gas connection (13) is closed and the second valve path (65) is connected to the third gas connection (15). [5] Monitoring arrangement (42) according to claim 4, characterized by that the valve tappet (2) comprises a projection or pin (3) which, when the test device (19) is connected, is engaged by a connecting element of the test device (19) and is pressed from the first switching position into the second switching position against its preload. [6] Monitoring arrangement (42) according to one of the preceding claims, characterized bythat at least one sensor device (18) for detecting at least one parameter selected from the group of parameters containing temperature, humidity, type of gas and presence of a decomposition product is in fluid communication with the first gas connection (13) and / or the second valve path (65). [7] Monitoring arrangement (42) according to one of the preceding claims, characterized by that the first valve path (64) is designed as a first gas connection (13) and the second valve path (65) is designed as a second gas connection (14) for connecting the monitoring device (46) to the multi-way valve device (44). [8] Monitoring arrangement (42) according to one of the preceding claims, characterized bythat the monitoring device (63) and the multi-way valve device (44) are designed separately, wherein the monitoring device (63) can be connected to the second valve path (65) or that the monitoring device (63) and the multi-way valve device (44) are integrated in a common unit or a common housing. [9] Monitoring arrangement (42) according to one of the preceding claims, characterized by that the monitoring device (63) has at least one density monitor (20) and / or one sensor device (18). [10] Electrical system (40) comprising a gas chamber (17) filled with a harmful gas and a monitoring arrangement (42) according to one of the preceding claims. [11] Monitoring method for monitoring at least one gas parameter of a harmful gas in an electrical system (40) by means of a monitoring device (43) comprising a multi-way valve device (44) and a monitoring device (63) for monitoring the at least one gas parameter, comprising the steps: Connecting the monitoring device (63) by means of the multi-way valve device (44) to the contaminating gas containing and with respect to the An electrical system (40) to be monitored for gas parameters, wherein the multi-way valve device (44) is connected to the system (40) via a first valve path (64) as a gas connection (13), wherein a gas transfer to the monitoring device (63) takes place via a second valve path (65) of the multi-way valve device (44), and wherein a third valve path (66) of the valve device (44) is used for a gas transfer to a testing device (19) for testing at least one function of the monitoring device (63), and the testing device (19) is connected to the third valve path (66) designed as a third gas connection (15), and selectively automatically connecting the second valve path (65) to the first valve path (64) or the third valve path (66) by means of an automatic switching device (56) of the multi-way valve device (44). [12] Use of a multi-way valve device (44) for connecting a monitoring device (63) for monitoring at least one gas parameter to an electrical system (40) containing a harmful gas and to be monitored with regard to the gas parameter, wherein the multi-way valve device (44) comprises a first valve path (64) which is used as a gas connection (13) for connecting the multi-way valve device (44) to the system (40), a second valve path (65) which is used for the gas transfer to the monitoring device (63), a third valve path (66) which is used for a gas transfer to a testing device (19) for checking at least one function of the monitoring device (63), and an automatic switching device (56) which is used for the selective automatic connection of the second valve path (65) to the first valve path (64) or the third valve path (66).

Images