Method for characterising a measuring point and for optimising the corresponding measuring point

Abstract

The invention relates to a method for characterising a measuring point (100), wherein measurement values (MW) detected by a first measuring device (1) are compared with one or more specified target measurement value ranges (SMW1; SMW2,...), each of which is associated with second measuring devices (21, 22,...) that can be installed at the measuring point (100). The measuring point (100) is evaluated with regard to suitability for one or more of the second measuring devices (21,...) on the basis of the comparison. The invention further relates to a method for optimising the measuring point (100), wherein the measuring point (100) has already been evaluated as part of the method for characterising the measuring point (100).

Description

[0001] Methods for characterizing a measuring point and for optimizing the corresponding measuring point

[0002] The invention relates to a method for characterizing a measuring point. Furthermore, the invention relates to a method for optimizing the measuring point. For example, the measuring point is a measuring point in a process plant of automation technology.

[0003] In automation technology, particularly process automation, field devices are used as measuring instruments at measuring points. For the purposes of this application, field devices are defined as all measuring instruments for determining and / or monitoring process variables that are installed close to the process at a measuring point in a process plant and provide and / or process process-relevant information. These include, for example, level gauges, flow meters, pressure gauges, humidity gauges, temperature gauges, pH and redox potential meters, conductivity meters, etc., which measure the corresponding parameters such as level, flow rate, pressure, humidity, temperature, pH value, or conductivity of a (process) medium. The applicant manufactures and distributes such field devices in a wide variety of configurations.

[0004] Depending on the type of measuring point, different types of field devices are suitable. Often, the user selects a suitable field device for their measuring point, taking into account the specific application, especially the expected measurement range. However, a user doesn't always have an overview of all measuring devices from a single manufacturer. Particularly if the application changes, an initial measuring device already installed at the measuring point may be less suitable than a different, alternative device.

[0005] The invention is based on the objective of providing a simple way to determine a measuring device that is (better) suitable for the measuring point.

[0006] The task is solved by a method for characterizing a measuring point and by a method for optimizing a measuring point.

[0007] Advantageous embodiments are specified in the dependent claims, wherein the method for optimization also includes, mutatis mutandis, all embodiments of the method for characterizing the measuring point and vice versa.

[0008] Regarding the characterization procedure, the problem is solved by a procedure for characterizing a measuring point, in particular a measuring point in a process plant of automation technology, the procedure comprising:

[0009] Providing a first measuring instrument for determining and / or monitoring a measurand, wherein the first measuring instrument is installed at the measuring point, recording measured values ​​for the measurand during a characterization period, using the first measuring instrument,

[0010] Reading one or more predefined target measurement ranges stored in a first database from the first database, wherein each of the predefined target measurement ranges is associated with a second measuring device, which can be installed at the measuring point and is different from the first measuring device, for determining and / or monitoring the measured quantity.

[0011] Comparison of the recorded measured values ​​with one or more predefined target measured value ranges,

[0012] Evaluating the measuring point with regard to its suitability for one or more of the second measuring devices, based on comparison.

[0013] The suitability assessment is carried out in-situ, where "in-situ" means that the assessment is carried out on site with the first measuring device installed at the measuring point, in particular during and / or alternating with the monitoring and / or determination of the measured quantity using the first measuring device.

[0014] This enables a user to determine the suitability of the measuring point for a further field device, in particular a second field device that differs from the first. The second field device or measuring instrument is, for example, a second field device manufactured by the same manufacturer, which is particularly suitable for the measuring point, in particular at least better suited, compared to the first field device. This assessment is carried out within the scope of the invention based on the data collected during the

[0015] The characterization period is determined using the measured values ​​obtained with the first field device. Preferably, the procedure is carried out essentially automatically, e.g., initiated by the first measuring device. As mentioned above, the characterization period can overlap with a measurement period. For example, the characterization period covers the entire

[0016] Operating time of the first measuring device, and / or a period which represents normal operation of the measuring point.

[0017] The first database, from which one or more target measurement ranges are read, is associated, for example, with a physical storage device. This storage device is comprised, in particular, of the first measuring device and / or the device communicating with the measuring device or configured to communicate with the measuring device. The first database can also be associated with a virtual storage device, such as a cloud, with which, for example, the first measuring device and / or the device are configured to communicate. In the latter case, it is advantageous if a second measuring device, which may not have been available when the first measuring device was installed, is subsequently added to the cloud with a target measurement range associated with this second measuring device. This allows the method according to the invention to detect that the measuring point may be unsuitable for the second measuring device.A second measuring device that is subsequently available is better suited, at least by means of the measured values ​​of the first measuring device.

[0018] In one form of the procedure, this includes

[0019] Determining a maximum and a minimum value for the measured quantity present at the measuring point during the characterization period, based on the recorded measured values; evaluating the measuring point as suitable for one or more of the second measuring devices, if at least the maximum and the minimum values ​​cover a measuring point measurement range in which the respective specified target measurement range is included.

[0020] In one embodiment of the procedure, the measuring point is evaluated by the first measuring device or by a device that communicates with the first measuring device or is designed to communicate with the first measuring device, wherein the device is in particular a mobile terminal and / or a control unit.

[0021] The mobile device and / or control unit can be a smartphone, a tablet, smart glasses, or a mobile device specifically designed for process automation, such as the FieldXpert distributed by the Endress+Hauser Group.

[0022] Of course, the method can also be implemented, especially at least partially, through the aforementioned cloud, e.g. by means of an evaluation algorithm stored therein, by means of which one or more of the steps of the method according to the invention are implemented.

[0023] In one embodiment of the method, a first target measurement range of the predefined target measurement ranges is associated with a second measuring device that can be installed at the measuring point and calibrated and / or validated in-situ at the measuring point. A predefined calibration range is stored in the first database, specifying which predefined calibration range lies within the first target measurement range and which predefined calibration range is relevant for calibrating the in-situ calibratable and / or validateable second measuring device. In this embodiment, the method comprises:

[0024] Reading the specified calibration range from the first database and

[0025] Assess the measuring point as suitable for the in-situ calibratable and / or validatable second measuring device, provided that at least the calibration range is included in the measuring point measurement range.

[0026] The calibration range is associated with the second measuring instrument in such a way that the second instrument, which can be calibrated and / or validated in situ, requires a specific calibration range. The second instrument should therefore receive measurements from within the calibration range so that it can be calibrated and / or validated in situ at the measuring point. In this configuration, the suitability of the measuring point for the in-situ calibrated and / or validated measuring instrument is verified.

[0027] In a further development of the aforementioned embodiment of the procedure, a predetermined upper limit change rate is stored in the first database, which predetermined upper limit change rate is associated with the second measuring device, which can be installed at the measuring point and is calibratable and / or validated in situ, in such a way that the upper limit change rate, for measured values ​​from the calibration range, limits a change rate range preferred for calibration, in particular a required range, from above, the procedure comprising:

[0028] Extracting the upper limit change rate from the first database,

[0029] Determining the maximum rate of change of measured values ​​present at the measuring point during the characterization period, for measured values ​​from the calibration range, and evaluating the measuring point as suitable for the in-situ calibratable and / or validatable measuring instrument if the maximum rate of change of measured values ​​is less than the upper limit rate of change.

[0030] The upper limit change rate is associated with the in-situ calibratable and / or validatable measuring instrument in such a way that the upper limit change rate for (or: on) measured values ​​from the calibration range limits a change rate range preferred for calibration, in particular a required one.

[0031] The upper limit change rate is, for example, an upper limit for a cooling rate, e.g., for the in-situ calibratable and / or validatable temperature measuring device mentioned below.

[0032] In one embodiment of the method, a predetermined lower limit change rate is stored in the first database, which predetermined lower limit change rate is associated with the second measuring device, which can be installed at the measuring point and is calibratable and / or validated in situ, such that the lower limit change rate, for measured values ​​from the calibration range, limits a change rate range preferred for calibration, in particular a required range, from below, the method comprising:

[0033] The process involves reading the specified lower limit change rate from the first database, recording the minimum measurement change rate present at the measuring point during the characterization period (for measurements within the calibration range), and evaluating the measuring point as suitable for the in-situ calibratable and / or validatable second measuring device if at least the minimum measurement change rate is greater than the lower limit change rate. The lower limit change rate is associated with the in-situ calibratable and / or validatable measuring device in such a way that, for (or at) measurement values ​​within the calibration range, the lower limit of the change rate range is defined from below as a preferred, and in particular required, range for calibration.

[0034] In one embodiment of the procedure, the measured quantity is at least one of the following:

[0035] Temperature, flow rate, pressure, fill level, conductivity, pH value, humidity.

[0036] Therefore, the first measuring device and the second measuring device are at least one of the following:

[0037] A temperature measuring device, a flow meter, a pressure measuring device, a level measuring device, a conductivity meter, a pH meter, a humidity meter.

[0038] In one embodiment of the procedure, the first target measurement range, the specified calibration range and, if applicable, in particular,the specified upper limit change rate and / or the specified lower limit change rate, associated with a temperature measuring device that can be installed at the measuring point and is in-situ calibratable and / or validatable as the second measuring device, which in-situ calibratable and / or validatable temperature measuring device comprises a temperature sensor and at least one reference element for in-situ calibration and / or validation of at least the temperature sensor, wherein the reference element consists at least partially of at least one material for which material in a temperature range relevant for the calibration of the temperature sensor at least one phase transition occurs at at least one specified phase transition temperature, for which phase transition the material remains in the solid phase, such that the calibration range is the temperature range relevant for the calibration of the temperature sensor.

[0039] Such a self-calibrating temperature measuring device is manufactured and marketed by the applicant under the trade name “iTherm TrustSens”. In this respect, reference is made to patent application EP 2 612 122 A1 and the associated patent specification EP 2 612 122 B1, to which full reference is made in the present patent application.

[0040] In a further development of the latter embodiment, a predetermined minimum initial time period is stored in the first database, which predetermined minimum initial time period is associated with the temperature measuring device that can be installed at the measuring point, calibrated in-situ and / or validated, the procedure encompassing:

[0041] Reading the specified minimum first time period from the first database, recording a time period during the characterization period during which the recorded measured values ​​are continuously above the calibration range, and evaluating the measuring point as suitable for the in-situ calibratable and / or validatable measuring device if at least the recorded time period is greater than the specified minimum first time period.

[0042] The minimum initial time period is associated with the in-situ calibratable and / or validatable temperature measuring device in such a way that it limits a preferred, and in particular required, exceedance period from below for calibration.

[0043] In one embodiment of the method, the first target measurement range, the specified calibration range and, if applicable, in particular the specified upper limit rate of change and the specified lower limit rate of change, are associated with a mass flow meter, in particular a Coriolis mass flow meter, which can be installed at the measuring point and is calibratable and / or validatable in situ, as the second measuring device, wherein in particular the specified upper limit rate of change and the specified lower limit rate of change define a range containing a rate of change of zero.

[0044] An in-situ calibratable Coriolis mass flow meter is disclosed in patent application DE 10 2022 112 523 A1, to which full reference is made for this embodiment within the scope of the present patent application.

[0045] In a further development of the above configuration, a predefined minimum second time period is stored in the first database, which predefined minimum second time period is associated with the mass flow meter that can be installed at the measuring point, calibrated in-situ and / or validated, the procedure comprising:

[0046] Reading the specified minimum second time period from the first database, recording a time period during the characterization period during which the recorded measurements continuously assume an essentially constant mass flow measurement value, in particular a mass flow measurement value of zero, such that during this time the mass flow measurement change rate is essentially zero, evaluating the measuring point as suitable for the in-situ calibratable and / or validatable mass flow measuring device if at least the recorded time period is greater than the specified minimum second time period.

[0047] In one embodiment of the procedure, this includes storing the existence of a calibration possibility, in particular together with an associated calibration possibility time, in the event that the measuring point, in particular at at least one calibration possibility time, is assessed as suitable for the in-situ calibratable and / or validatable measuring instrument, wherein the existence of the calibration possibility, in particular together with the associated calibration possibility time, is stored in the first database and / or a second database.

[0048] The second database is also associated with physical storage, which in turn is comprised of, for example, the first measuring device and / or the device communicating with the measuring device or designed to communicate with the measuring device. The second database can also be associated with virtual storage, such as a modern cloud, with which, for example, the first measuring device and / or the device designed to communicate with the measuring device is configured.

[0049] In one embodiment of the method, the first measuring device comprises a time recording unit, in particular an operating hours counter, and the method comprises:

[0050] Taking into account time measurements recorded by the time recording unit when determining at least one of the following: the maximum measurement change rate, the minimum measurement change rate, the recorded time duration, the calibration opportunity time.

[0051] In one embodiment of the procedure, if a calibration opportunity is available for the measuring point at different times during the characterization period, at least one of the following characterization parameters is determined and stored, in particular in the first database and / or the second database: a total number of calibration opportunities during the characterization period, a time interval since the last calibration opportunity, a time interval averaged over the entire duration of the characterization period between two successive calibration opportunities, a time rate of successive calibration opportunities averaged over the entire duration of the characterization period.

[0052] For the averaged calibration time and / or averaged time rate, for example a mean value, a median, or a comparable known averaging method is used.

[0053] Naturally, the term "characterization parameter" also includes one or more of the parameters already mentioned above that are present and / or determined during the characterization period, including: the measurement point measurement range, the maximum measurement rate of change and minimum measurement rate of change present during the characterization period, in the case of measurement values ​​from the calibration range.

[0054] In one embodiment of the procedure, the procedure includes the following in the event that the measuring point is deemed suitable for several second and each different type of measuring device:

[0055] Comparative evaluation, in particular including the creation of a ranking of the suitability of the several second measuring devices, based on at least a comparison of the recorded measured values ​​with the several target measured value ranges.

[0056] In one embodiment of the procedure, at least one of the following is displayed by means of a display, in particular a virtual or physical one.

[0057] The assessment of the measuring point as suitable or unsuitable for one or more of the second measuring devices,

[0058] One or more of the characterization parameters, if available and if the measuring point was assessed as suitable for at least one of the second measuring devices; a result of the comparative assessment, in particular the ranking.

[0059] The aforementioned comparative assessment compares the suitability of different, fundamentally suitable second measurement variables based on at least the steps mentioned above.

[0060] The invention may further include the provision of a physical display unit, in particular with a display, wherein the display is a physical display, which physical display is shown on a physical display unit, and wherein the physical display unit is included by the first measuring device or the device.

[0061] Regarding the procedure for optimizing a measuring point, the problem is solved by a procedure for optimizing a measuring point, the procedure comprising:

[0062] Characterizing the measuring point, wherein a first measuring device is installed at the measuring point and, according to the inventive method,

[0063] Removal of the first measuring device and installation of a second measuring device at the measuring point, in place of the first measuring device, in the event that the measuring point is assessed as suitable for the second measuring device during the characterization of the measuring point, in particular the one of the measuring devices which was assessed as most suitable for the measuring point, in the case of comparative assessment.

[0064] In one embodiment of the method, the second measuring device is a second measuring device designed for in-situ calibration and / or validation.In one embodiment of the method, the first measuring device is a temperature measuring device, and the second measuring device, designed for in situ calibration and / or validation, is an in situ calibratable and / or validatable temperature measuring device, which temperature measuring device comprises a temperature sensor and at least one reference element for in situ calibration and / or validation of at least the temperature sensor, wherein the reference element consists at least partially of at least one material for which material, in a temperature range relevant for the calibration of the temperature sensor, at least one phase transition occurs at at least one predetermined phase transition temperature, for which phase transition the material remains in the solid phase, and wherein the calibration range is the temperature range relevant for the calibration of the temperature sensor.

[0065] The invention is explained in more detail with reference to the following figures, which are not to scale, where identical reference numerals denote identical features. Where clarity requires it or where it otherwise appears appropriate, previously mentioned reference numerals are omitted in subsequent figures.

[0066] They show:

[0067] Fig. 1 : A measuring point 100 with a first measuring device 1, which is installed at the measuring point 100, in an embodiment of the invention;

[0068] Fig. 2a: A flowchart for steps of the inventive method in one embodiment of the invention;

[0069] Fig. 2b: A graph in which the recorded temperature measurements MW are plotted against the time t of the characterization period CZ; and

[0070] Fig. 3: An embodiment of the method for optimizing measuring point 100.

[0071] Without limiting the generality of the invention, for the sake of clarity, it will now and in the following be explained using a temperature measuring device as the first measuring device 1 and temperature as the measured quantity. The invention naturally also encompasses, mutatis mutandis, other types of measuring devices, including, for example, the aforementioned flow meter.

[0072] The first measuring device 1 comprises a temperature sensor, for example, a resistive element such as a so-called PTC thermistor (PTC stands for positive temperature coefficient). PTC thermistors are characterized by the fact that their resistance increases linearly with rising temperature, especially in the first order. Platinum is widely used among PTC thermistors because platinum exhibits a resistance that is at most quadratic in its dependence on temperature.

[0073] The resistance element is designed, for example, to exhibit a specific nominal resistance at a reference temperature, such as 0°C, and is accordingly designated as Pt10 (10 ohms), Pt100 (100 ohms), and Pt1000 (1 kOhm). In a temperature sensor in the form of a thermocouple, the temperature is measured using a thermoelectric voltage generated between thermocouple wires made of different materials connected at one end. Thermocouples conforming to DIN standard IEC 584, such as types K, J, N, S, R, B, T, or E, are commonly used for temperature measurement.

[0074] The temperature sensor, as well as connecting leads at least partially attached to the sensor element, are arranged within a lumen of an elongated measuring insert enclosing the sensor element, particularly in a distal end region. The temperature sensor and at least partially the connecting leads are enclosed and / or encapsulated within the lumen or interior of the measuring insert in an electrically insulating material, e.g., a ceramic powder, especially magnesium oxide (MgO) or aluminum oxide (Al₂O₃), or a ceramic potting compound, particularly a hardening one.

[0075] The measuring insert is located inside an immersion body 9, in particular a protective tube. The measuring insert can be removed from the protective tube, especially repeatedly, for example for replacement and / or maintenance purposes. The immersion body 9 or the protective tube is connected via a process connection to a container holding the medium (here: a pipeline carrying the medium), whereby the measuring point 100, comprising the first measuring instrument 1, is formed.

[0076] For processing and / or forwarding a measurement signal generated by the temperature sensor, the first measuring device 1 has a (head) transmitter unit which is mechanically connected to the measuring insert, in particular at a proximal end region of the measuring insert. The transmitter unit includes measuring electronics for processing and / or forwarding measurement signals acquired by the temperature sensor. The measuring electronics provide the measured values ​​MW acquired by the first measuring device 1 during a characterization period CZ. The first measuring device 1 includes a time recording unit 5, e.g., an operating hours counter, which is, for example, enclosed by the measuring electronics.

[0077] A device 4 is equipped to communicate with the first measuring device 1 via a communication link, in particular a wireless communication link. Device 4 is a mobile terminal, e.g., a smartphone, a tablet, smart glasses, and / or a mobile terminal specifically designed for process automation technology, such as the FieldXpert distributed by the applicant. Within the scope of this application, the term "mobile terminal" also includes all other mobile devices that are configured for communication – preferably wireless – with the first measuring device 1.

[0078] The measured values ​​MW for the temperature recorded by the first measuring device 1 during the characterization period CZ, together with the corresponding time points recorded by the time recording unit 5, are transmitted to the device 4 via the at least unidirectional communication link in the configuration shown in Fig. 1.

[0079] In addition, one or more predefined target measurement ranges SMW1, SMW2, ... , each associated with a second temperature measuring device 2; 21; 22; ... , are read from a first database 31. The first database 31 and one or more predefined target measurement ranges SMW1, SMW2, ... stored therein are therefore part of the subject matter of the invention, "method for characterization". The respective predefined target measurement range SMW1; SMW2; ... is preferred, in particular required, when using a second measuring device 2 that can be installed at the measuring point 100.

[0080] The device 4 now compares, for example by means of an algorithm implemented therein to execute the procedure, the measuring point measurement range Int, which is limited by the maximum and the minimum of the measured values ​​MW recorded during the characterization period CZ, with the one or more predefined target measurement ranges SMW1 , SMW2, ... .

[0081] The invention is not limited to the use of the device 4 shown in this embodiment. Depending on the configuration, e.g., of the first measuring device 1 or its measuring electronics, the method according to the invention can, mutatis mutandis, also be implemented at least partially or completely in the first measuring device 1, in particular its steps being carried out by the first measuring device, especially in a substantially automated manner. For example, the first measuring device 1 itself determines the characterization parameters CG1, CG2,... and optionally displays them on a display, such as a screen of the first measuring device 1. Furthermore, the method according to the invention can, mutatis mutandis, also rely on a fixed (control) device, e.g., a programmable logic controller (PLC) and / or a cloud for the implementation of its steps.

[0082] The invention is used, for example, to test the suitability of measuring point 100 for a second, in-situ calibratable temperature measuring device 21a that can be installed at measuring point 100. For in-situ calibration and / or validation of the in-situ calibratable second measuring device 21, a predefined temperature range should be observed as the calibration range KB from measuring point 100 during normal (measuring and / or cleaning) operation. For example, the in-situ calibratable second temperature measuring device 21a, marketed under the name "iTherm TrustSens" (not shown here, see Fig. 3), has a reference element 8 for in-situ calibration and / or validation of at least the temperature sensor 7.

[0083] The reference element 8 consists at least partially of a material for which at least one phase transition occurs at at least one predetermined phase transition temperature within a temperature range relevant for calibrating the temperature sensor 7. In this case, the calibration range KB is the temperature range relevant for calibrating the temperature sensor 7. Therefore, the device 4 is used to check whether the measuring point 100 would meet the criteria for in-situ self-calibration if the in-situ calibratable second temperature measuring device 21a were installed at the measuring point 100 instead of the first measuring device 1.

[0084] This is explained in more detail in connection with Figures 2a and 2b, where Figure 2a shows a flowchart of process steps. Figure 2b shows a time course of recorded measured values ​​MW, i.e., temperature versus (operating) time, plotted together with the criteria for in-situ self-calibration.

[0085] In a first step, the maximum (Max) and minimum (Min) measured values ​​(MW) experienced by the first measuring device 1 at measuring point 100 during the characterization period CZ are checked. This step is shown in Box A) of Fig. 2a. For this purpose, the values ​​for the maximum (Max) and minimum (Min) can be continuously recorded by the measuring electronics, for example, as with a simple drag pointer.

[0086] In a subsequent step – see Box B) in Fig. 2a – it is checked whether the recorded temperature measurements MW cover at least the specified calibration range KB. Additionally, it can be checked, for example, whether the temperature at measuring point 100 was above the specified calibration range KB for at least a recorded time period t greater than a specified minimum initial time period tminl, i.e., long enough, as shown in Fig. 2b.

[0087] In a subsequent step – see Box C) in Fig. 2a and the recorded rate of change in Fig. 2b – it is determined whether a recorded rate of change of the measured quantity, for measured values ​​from the specified calibration range KB, is greater than a specified lower rate of change Rt_min and less than a specified lower rate of change Rt_max. For the self-calibration of the in-situ calibratable second temperature measuring device 21a, it is preferred if the cooling rate is neither too low nor too high. A maximum / minimum value of the rate of change present during the characterization period CZ can also be recorded using a type of drag pointer.

[0088] If the criteria queried in steps B) and C) are not met, measuring point 100 is deemed unsuitable for the in-situ calibratable second temperature measuring device 21a (see crossed-out box). If measuring point 100 is deemed suitable for the in-situ calibratable second temperature measuring device 21a, the availability of a calibration option at measuring point 100 is recognized. If applicable – see box D) in Fig. 2a – the number of calibration options is recorded as a characterization parameter CG1; a drag indicator may also be used here. One or more of the characterization parameters CG1, CG2, ... determined by the method are displayed on a display 6, e.g., of the device 4 (see also Fig. 1).

[0089] The invention includes, for example, a display such as: "If an iTHERM TrustSens were used, this measuring point 100 would have already performed 50 self-calibrations, most recently 8 operating hours ago during a total operating time of 450 operating hours. This corresponds to a self-calibration rate of 3 self-calibrations per month." This display 6 is then optionally summarized under a headline "Ready for iTHERM TrustSens."

[0090] Fig. 3: finally shows another embodiment of the method for optimizing the measuring point 100. In this case, the first measuring device 1 is removed if the measuring point 100 has been evaluated as suitable for the in-situ calibratable second temperature measuring device 21a within the framework of the inventive method for characterization, and the in-situ calibratable second temperature measuring device 21a, which comprises an immersion body (or protective tube) 9 and a measuring insert with a temperature sensor ? and a reference element 8, is installed in its place.

[0091] In the event that both the first measuring instrument 1 and the in-situ calibratable second measuring instrument 21 have a similar immersion body 9, when replacing the first temperature measuring instrument 1 with the in-situ calibratable second temperature measuring instrument 21a, the immersion body 9 at the measuring point 100 can remain in its installed state and, advantageously, for example, only the measuring insert and the transmitter unit need to be replaced.

[0092] Reference signs and symbols

[0093] 100 measuring points

[0094] 1 first measuring device

[0095] 21, 22 second measuring device, associated with target measurement range

[0096] 21 in-situ calibratable second measuring device

[0097] 21a in-situ calibratable temperature measuring device

[0098] 21 b in-situ calibratable flowmeter

[0099] 31, 32 first, second database

[0100] 4 Device

[0101] 5 Time recording unit

[0102] 6 ads

[0103] 7 Temperature sensor

[0104] 8 Reference element

[0105] 9 Protective tube

[0106] MW recorded measurements

[0107] CZ Characterization Period

[0108] SMW1, SMW2, ... specified target measurement ranges

[0109] Maximum of measured values

[0110] Minimum of recorded measured values

[0111] Int measuring point measurement range

[0112] KB specified calibration range

[0113] Rt_max, Rt_min: predefined upper / lower limit rate of change; tminl, tmin12: predefined minimum first, second duration

[0114] CG1, CG2, CG3, CG4, .... Characterization parameters

Claims

Patent claims 1. Method for characterizing a measuring point (100), in particular a measuring point in a process plant of automation technology, the method comprising: Providing a first measuring device (1) for determining and / or monitoring a measurand, wherein the first measuring device (1) is installed at the measuring point (100), recording measured values ​​(MW) for the measurand during a characterization period (CZ), using the first measuring device (1), Reading one or more predefined target measurement ranges (SMW1 ; SMW2, ...) stored in a first database (31) from the first database (21), wherein each of the predefined target measurement ranges (SMW1 ; SMW2, ...) is associated with a second measuring device (21 , ...) that can be installed at the measuring point (100) and is different from the first measuring device (1) for determining and / or monitoring the measured quantity, Comparison of the recorded measured values ​​(MW) with one or more predefined target measured value ranges (SMW1 ; SMW2, ...), Evaluating the measuring point (100) with regard to its suitability for one or more of the second measuring devices (21 , ...), based on the comparison.

2. A method for characterizing according to claim 1, comprising: Determining a maximum value (Max) and a minimum value (Min) for the measured quantity present at the measuring point (100) during the characterization period (CZ), based on the recorded measured values ​​(MW), Evaluate the measuring point (100) as suitable for one or more of the second measuring devices (21 ; ...), if at least the maximum value (Max) and the minimum value (Min) cover a measuring point measurement range (Int) in which the respective specified target measurement range (SMW1 ; SMW2, ...) is included.

3. Method according to claim 1 or 2, wherein the measuring point (100) is evaluated by the first measuring device (1) or by a device (4) which communicates with the first measuring device (1) or is designed to communicate with the first measuring device (1), wherein the device (4) is in particular a mobile terminal and / or a control unit.

4. Method according to at least one of the preceding claims, wherein a first target measurement range (SMW1) of the specified target measurement ranges (SMW1; SMW2,...) is associated with a second measuring device (21) that can be installed at the measuring point (100) and calibrated and / or validated in-situ at the measuring point, and wherein a specified calibration range (KB) is stored in the first database, which specified calibration range (21) lies within the first target measurement range (SMW1) and which where the specified calibration range (KB) is a relevant measurement range for the calibration of the in-situ calibratable and / or validatable second measuring instrument (21), the procedure comprises: reading the specified calibration range (KB) from the first database (31) and evaluating the measuring point (100) as suitable for the in-situ calibratable and / or validatable second measuring instrument (21), if at least the calibration range (KB) is included in the measuring point measurement range (Int).

5. Method according to at least claim 4, wherein a predetermined upper limit change rate (Rt_max) is stored in the first database (31), which predetermined upper limit change rate (Rt_max) is associated with the second measuring device (21) that can be installed at the measuring point (100), calibrated in situ and / or validated, such that the upper limit change rate (Rt_max) limits a change rate range preferred for calibration, in particular a required range, from above for measured values ​​from the calibration range (KB), the method comprising: Reading the upper limit change rate (Rt_max) from the first database (31), recording a maximum measurement change rate present at the measuring point (100) during the characterization period (CZ), for measurement values ​​from the calibration range (KB), and Evaluate the measuring point (100) as suitable for the in-situ calibratable and / or validatable measuring device (21) if at least the maximum rate of change of measured values ​​is less than the upper limit rate of change (Rt_max).

6. Method according to claim 4 or 5, wherein a predetermined lower limit change rate (Rt_min) is stored in the first database (31), which predetermined lower limit change rate (Rt_min) is associated with the second measuring device (21) that can be installed at the measuring point (100), calibrated in situ and / or validated, such that the lower limit change rate (Rt_min) limits a change rate range preferred for calibration, in particular required, from below for measured values ​​from the calibration range (KB), the method comprising: Reading the specified lower limit rate of change (Rt_min) from the first database (31), Determining a minimum rate of change of measured values ​​present at the measuring point (100) during the characterization period (CZ), for measured values ​​from the calibration range (KB), and Evaluate the measuring point (100) as suitable for the in-situ calibratable and / or validatable second measuring device (21) if at least the minimum measured value change rate is greater than the lower limit value change rate (Rt_min).

7. Method according to at least one of the following claims, wherein the measured quantity is at least one of the following: Temperature, flow rate, pressure, fill level, conductivity, pH value, humidity, 8. Method according to at least one of the following claims 3 to 7, wherein the first target measurement range (SMW1), the predetermined calibration range (KB) and, if applicable, in particular the predetermined upper limit change rate (Rt_max) and / or the predetermined lower limit change rate (Rt_min), are associated with a temperature measuring device (21a) that can be installed at the measuring point (100) and is in-situ calibratable and / or validatable, which is the second measuring device (21a), which in-situ calibratable and / or validatable temperature measuring device (21a) comprises a temperature sensor for detecting the temperature and at least one reference element for in-situ calibration and / or validation of at least the temperature sensor, wherein the reference element consists at least partially of at least one material for which at least one phase transition occurs at at least one predetermined phase transition temperature in a temperature range relevant for the calibration of the temperature sensor.for which phase transition the material remains in the solid phase, such that the calibration range (KB) is the temperature range relevant for calibrating the temperature sensor.

9. Method according to claim 8, wherein a predetermined minimum first time period (tminl) is stored in the first database (31), which predetermined minimum first time period (tminl) is associated with the temperature measuring device (21a) that can be installed at the measuring point (100) and is calibratable and / or validated in situ, the method comprising: Reading the specified minimum first time duration (tminl) from the first database (31), Recording the duration during the characterization period (CZ) during which the recorded measured values ​​(MW) are continuously above the calibration range (KB). Evaluate the measuring point (100) as suitable for the in-situ calibratable and / or validatable temperature measuring device (21a) if at least the recorded time duration is greater than the specified minimum first time duration (tminl).

10. Method according to at least one of the following claims 3 to 7, wherein the first target measurement range (SMW1), the specified calibration range (KB) and, if applicable, in particular the specified upper limit rate of change (Rt_max) and the specified lower limit rate of change (Rt_min), with a mass flow meter (21 b) that can be installed at the measuring point (100), which can be calibrated and / or validated in situ, in particular a Coriolis mass flow meter, as the second measuring device (21), and wherein in particular the specified upper limit rate of change (Rt_max) and the specified lower limit rate of change (Rt_min) limit a range containing a rate of change of zero.

11. Method according to claim 10, wherein a predetermined minimum second time period (tmin2) is stored in the first database (31), which predetermined minimum time period (tmin2) is associated with the mass flow meter (21 b) that can be installed at the measuring point (100) and is calibratable and / or validated in situ, the method comprising: Reading the specified minimum second time duration (tmin2) from the first database (31), Recording a time period during the characterization period (CZ) during which the recorded measurements (MW) continuously assume a substantially constant mass flow measurement value, in particular a mass flow measurement value of zero, such that during this time the mass flow measurement rate of change is substantially zero. Evaluate the measuring point (100) as suitable for the in-situ calibratable and / or validatable mass flow meter (21 b) if at least the recorded time duration is greater than the specified minimum second time duration (tmin2).

12. Method according to at least one of the preceding claims 4 to 9 or 10 to 11, comprising: Storing the existence of a calibration possibility, in particular together with an associated calibration possibility time, in the event that the measuring point (100) is assessed as suitable for the in-situ calibratable and / or validatable measuring instrument (21), wherein the existence of the calibration possibility, in particular together with an associated calibration possibility time, is stored in the first database (31) and / or a second database (32).

13. Method according to at least one of the preceding claims, wherein the first measuring device (21 ; ...) comprises a time recording unit (5), in particular an operating hours counter, the method comprising: Taking into account time measurements recorded by means of the time recording unit (5) when determining at least one of the following: the maximum measured value- Rate of change, minimum measurement rate of change, recorded time duration, calibration opportunity time.

14. Method according to claim 12 or 13, wherein, in the event that a calibration opportunity is available for the measuring point (100) at different times during the characterization period (CZ), at least one of the following characterization parameters (CG1; CG2; CG3; CG4) is determined and stored, in particular in the first database (31) and / or the second database (32): a total number of calibration opportunities (CG1) during the characterization period (CZ), a time interval (CG2) elapsed since the last calibration opportunity, a time interval (CG3) averaged over the entire duration of the characterization period (CZ) between two successive calibration opportunities, and a time rate (CG4) averaged over the entire duration of the characterization period (CZ) of successive calibration opportunities.

15. Method according to at least one of the preceding claims, wherein, in the event that the measuring point (100) is deemed suitable for several second and each different measuring devices (21 , 22; ...) the method comprises: Comparative evaluation, in particular including the creation of a ranking of the suitability of the second measuring instruments (21 , 22; ...), at least on the basis of a comparison of the recorded measured values ​​(MW1) with the several target measured value ranges (SMW1 , SMW2, ...).

16. Method according to at least one of the preceding claims, wherein at least one of the following is displayed by means of a display (6), in particular a virtual or physical display. The assessment of the measuring point (100) as suitable or unsuitable for one or more of the second measuring devices (21 ; 22...), One or more of the characterization parameters (CG1 ; CG2; CG3, CG4, ...), if available and if the measuring point (100) has been assessed as suitable for at least one of the second measuring devices (21 ; 22; ...), One result of the comparative evaluation, especially the ranking.

17. Method for optimizing a measuring point (100), comprising: Characterizing the measuring point (100) according to the method of one of the preceding claims, wherein a first measuring device (2) is installed at the measuring point (100) and, removing the first measuring device (1) and installing a second measuring device (21; 22...) at the measuring point (100) in place of the first measuring device (1), in the event that the measuring point (100) is found to be unsuitable for the second measuring device during the characterization of the measuring point (100). (21; 22,...) is appropriately evaluated, in particular the measuring device (21, 22,...) which was evaluated as being most suitable for the measuring point (100) in the case of comparative evaluation.

18. Method Claim 17, wherein the second measuring device (21, 22, ...) is a device suitable for in-situ Calibration and / or validation of a trained second measuring instrument (21).

19. Method Claim 18, wherein the first measuring device (1) is a The temperature measuring device is a temperature measuring device, and the second measuring device (21) designed for in situ calibration and / or validation is a temperature measuring device (21a), which temperature measuring device (21a) comprises a temperature sensor (7) for detecting the temperature and at least one reference element (8) for in situ calibration and / or validation of at least the temperature sensor (7), wherein the reference element (8) consists at least partially of at least one material for which material in a temperature range relevant for the calibration of the temperature sensor (7) at least one phase transition occurs at at least one predetermined phase transition temperature, for which phase transition the material remains in the solid phase, and wherein the calibration range is the temperature range relevant for the calibration of the temperature sensor (7).

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