FIELD DEVICE WITH PROCESS-SPECIFIC CONDITION MONITORING CAPABILITY

Abstract

The present invention relates to an apparatus for determining and/or monitoring at least one process variable of a medium, comprising a sensor unit for registering a value for the process variable, a time registration unit for registering at least one duration of operation and a calculating unit, which is embodied at least based on the duration of operation registered by the time registration unit and based on at least one influencing variable influencing the duration of operation to make at least one statement with reference to condition of at least one component of the apparatus. Furthermore, the present invention relates to a method for operating an apparatus of the invention.

Claims

1-15. (canceled)

16. An apparatus for determining and monitoring at least one process variable of a medium, comprising a sensor unit for registering a value for the process variable; a time registration unit for registering a duration of operation; and a calculating unit embodied at least based on the duration of operation registered by the time registration unit and based on at least one influencing variable influencing the duration of operation to make at least one statement with reference to condition of at least one component of the apparatus.

17. The apparatus as claimed in claim 16, wherein the influencing variable is a process parameter, a process variable or an environmental parameter, including a temperature of the process or of a component of the apparatus; a pressure, including a pressure in a container in which the medium is located; a moisture content, including a humidity of the surroundings; vibrations which occur in the region of the apparatus; flow of the medium; a pH value of the medium; or a conductivity of the medium.

18. The apparatus as claimed in claim 16, further comprising: a measuring unit for registering a value for the influencing variable, wherein the measuring unit is an apparatus for determining a temperature, a pressure, a moisture content, an apparatus for detecting vibrations, or an apparatus for determining a flow, a pH value, or a conductivity.

19. The apparatus as claimed in claim 16, further comprising: a first and a second module, wherein the calculating unit is embodied at least based on the duration of operation registered by the time registration unit and based on at least one influencing variable influencing the duration of operation to make a first statement with reference to condition of the first module of the apparatus and a second statement with reference to condition of the second module of the apparatus, or wherein two calculating units are present, wherein a first calculating unit is embodied to make the first statement with reference to condition of the first module, and wherein a second calculating unit is embodied to make the second statement with reference to condition of the second module.

20. The apparatus as claimed in claim 19, wherein the first module is the sensor unit of the apparatus and/or the second module is an electronics unit of the apparatus.

21. The apparatus as claimed in claim 16, further comprising: a display unit for a visual display of the at least one statement with reference to condition of the component of the apparatus.

22. A method for operating an apparatus for determining and monitoring at least one process variable of a medium, comprising: providing the apparatus, including: a sensor unit for registering a value for the process variable; a time registration unit for registering a duration of operation; and a calculating unit embodied at least based on the duration of operation registered by the time registration unit and based on at least one influencing variable influencing the duration of operation to make at least one statement with reference to condition of at least one component of the apparatus; registering a value for the at least one process variable; registering a duration of operation; and making at least one statement with reference to condition of the at least one component of the apparatus, wherein the statement is made at least based on the registered duration of operation and based on at least one influencing variable influencing the duration of operation.

23. The method as claimed in claim 22, wherein the statement with reference to condition of the at least one component of the apparatus is a process specific duration of operation of the at least one component of the apparatus.

24. The method as claimed in claim 22, wherein the statement with reference to condition of the at least one component of the apparatus is a probability for occurrence of a defect or a failure of the at least one component of the apparatus.

25. The method as claimed in one of claim 22, wherein the statement with reference to condition of the at least one component of the apparatus is a loading of the at least one component of the apparatus.

26. The method as claimed in one of claim 22, wherein a statement is made with reference to condition of an additional apparatus, which serves for monitoring the medium.

27. The method as claimed in one of claim 22, wherein at least first and second value ranges are predetermined for the influencing variable.

28. The method as claimed in claim 27, wherein statements with reference to at least one component of the apparatus are made for each of the at least two value ranges.

29. The method as claimed in claim 27, wherein a weighting factor is specified for at least one value range.

30. The method as claimed in claim 29, wherein the statement concerning the at least one component of the apparatus is made based on the at least two value ranges for the influencing variable and based on the at least one weighting factor.

Description

[0033] FIG. 1 a first embodiment of an apparatus of the invention having a sensor unit, a time registration unit, a calculating unit and an additional measuring unit,

[0034] FIG. 2 a second embodiment of an apparatus of the invention with two calculating units as well as a display unit,

[0035] FIG. 3 examples for the specification of different value ranges for an influencing variable, and

[0036] FIG. 4 an apparatus of the invention in the form of a thermometer with two modules

[0037] In the figures, equal elements are provided with equal reference characters.

[0038] FIG. 1 shows a field device 1 for determining and/or monitoring at least one process variable P of a medium M, wherein the medium M is located in a container 2. Of course, a medium M in the context of the present invention can, however, also be located in some other kind of containment, for example, a pipeline, and even have no containment whatever.

[0039] The apparatus 1 includes a sensor unit 3 for registering a value for the particular process variable P as well as an electronics unit 4. Involved in the present example is a modular field device 1 of compact construction, wherein a first module is provided by the sensor unit 3 and a second module by the electronics unit 4. However, also other types of field devices fall within the scope of the present invention.

[0040] Arranged in the electronics unit 4 is a time registration unit 5 for registering at least one duration of operation t of the apparatus 1. Moreover, the electronics unit 4 includes a calculating unit 6. It is to be noted here that the time registration unit 5 and calculating unit 6 do not have to be arranged within electronics unit 4. They can as well also be arranged outside of the same.

[0041] The apparatus 1 additionally includes a measuring unit 7 for registering a value for the influencing variable IV. Such in the present example is arranged such as the sensor unit 3 such that it registers a process parameter p of the medium M. In other embodiments, the measuring unit 7 can also be embodied for determining an environmental parameter e, thus, a parameter outside of the medium M and/or container 2. The process parameter p is, for example, the temperature or the pressure of the medium. As described above, however, also other process parameters can be taken into consideration.

[0042] According to the invention, the calculating unit 6 is embodied based on the duration of operation t registered by the time registration unit 5 and based on at least the influencing variable IV influencing the duration of operation t to make at least one statement with reference to condition of the apparatus 1. This statement can be, for example, a process specific duration of operation t.sub.p of the apparatus 1, a probability for occurrence of a defect or a failure of the apparatus 1, or a loading of the apparatus.

[0043] FIG. 2 shows a second possible embodiment for an apparatus 1 of the invention. In contrast with FIG. 1, this apparatus 1 includes a first calculating unit 6 and a second calculating unit 8. The first calculating unit 6 is so embodied at least based on the duration of operation t registered by the time registration unit 5 and the second calculating unit 8 is embodied based on at least one influencing variable IV the duration of operation t to make a first statement with reference to condition of the sensor unit 3 and a second statement with reference to condition of the electronics unit 4 of the apparatus 1. The first and second calculating unit 6, 8 can for ascertaining the first and second statements take into consideration the same influencing variable IV or different influencing variables IV1, IV2. In other embodiments, in turn, a plurality of statements, especially the two, concerning the electronics unit 4 and the sensor unit 3, can be ascertained by means of the same calculating unit 6. Also, each module 3, 4 can have its own time registration unit 5, 9 [the second time registration unit is drawn dashed].

[0044] Moreover, the apparatus 1 of FIG. 2 includes a display unit 10. This serves for the, especially visual, display of the at least one statement with reference to condition of the apparatus 1. For the embodiment shown here, the display unit 10 is likewise associated with the electronics unit 4. In other embodiments, the display unit can be a separate unit.

[0045] It is to be noted here that the individual components of the apparatuses of FIGS. 1 and 2 in other embodiments can also be combined with one another in other ways. The illustrated embodiments are, thus, to be considered only as individual, possible examples.

[0046] Shown in FIG. 3 are possible examples for the specification of individual value ranges for an apparatus 1 of the invention, or fora method of the invention. For the examples of FIGS. 3a and 3b, two v.sub.1, v.sub.2, or three equally long value ranges v.sub.1-v.sub.3, were predetermined for the influencing variable IV. In the case of FIG. 3c, in contrast, four differently large value ranges v.sub.1-v.sub.4 were predetermined. The value ranges v are, in such case, preferably predetermined, or correspondingly selected, as a function of the influence IV on the duration of operation t of the apparatus 1. It is then, for example, an option, to make for each of the value ranges v, in each case, a statement with reference to apparatus 1, or, for at least one of the value ranges v, a weighting factor can be specified. Then it is, in turn, possible to make the statement concerning the apparatus based on the at least two value ranges v.sub.1, v.sub.2 for the influencing variable IV and based on the at least one weighting factor.

[0047] Another option for additional embodiments is obtained by specifying differently many value ranges v for the different modules 3, 4 of the apparatus 1, or different value ranges v for different influencing variables IV. The different statements can, in such case, be ascertained in a single calculating unit 6 or in a plurality of processing units 6, 8.

[0048] It is to be noted here that for the embodiments shown in FIG. 1-FIG. 3 instead of statements concerning the entire apparatus 1 also different statements can be made for different modules, for example, an electronics unit 4 or a sensor unit 3.

[0049] FIG. 4 shows another example of an embodiment of the present invention with an apparatus in the form of a thermometer 1. Thermometer 1 includes a sensor unit 3 in the form of a resistance element, which is connected with the electronics unit 4 via two connection lines 11a, 11b. In other embodiments, for example, also a sensor element 3 with a thermocouple can be used. In principle, all sensor units 3 known from the state of the art and used in connection with thermometers 1 can be put to use.

[0050] For the example of an embodiment shown in FIG. 4, the temperature T of the medium is both the process variable P as well as also the influencing variable IV. Correspondingly, no separate measuring unit 7 is needed for the apparatus 1 of FIG. 4.

[0051] Usually in the case of thermometers 1, different maximum temperatures are permitted for the sensor unit 3 and for the electronics unit 4. An operating of the particular module, thus, the sensor unit 3, or the electronics unit 4, at relatively high temperatures T, i.e. at temperatures near the maximum allowable operating temperature, leads to an increased probability for occurrence of defects in the particular modules 3,4, or can make a replacement of the particular module necessary at an earlier point in time than in a case, in which the thermometer 1 is operated only at lower temperatures T. Thus, the temperature T of the medium represents an influencing variable IV influencing the duration of operation t of the apparatus 1. In the context of the present invention, for the entire apparatus 1, or separately for different modules 3, 4 and/or for different value ranges, a statement can be made in each case. Or, weighting factors can be ascertained for the different modules 3, 4 and/or value ranges. Based on the different statements or based on the individual statements and the corresponding weighting factors, then, for example, a process specific duration of operation t.sub.p can be ascertained for one of the modules 3, 4 or for the apparatus 1.

[0052] Advantageously, the present invention enables a reliable and exact condition monitoring based on the duration of operation t of the apparatus and based on at least one influencing variable influencing the duration of operation t.

REFERENCE CHARACTERS

[0053] 1 apparatus [0054] 2 container [0055] 3 sensor unit [0056] 4 electronics unit [0057] 5 time registration unit [0058] 6 calculating unit [0059] 7 measuring unit [0060] 8 second calculating unit [0061] 9 second time registration unit [0062] 10 display unit [0063] 11 11a, 11b connection lines [0064] M medium [0065] P process variable [0066] IV influencing variable [0067] p process parameter [0068] e environmental parameter [0069] T temperature [0070] v value ranges [0071] t duration of operation [0072] t.sub.p process specific duration of operation