(19)
(11)EP 3 222 976 B1

(12)EUROPEAN PATENT SPECIFICATION

(45)Mention of the grant of the patent:
09.09.2020 Bulletin 2020/37

(21)Application number: 17161962.0

(22)Date of filing:  21.03.2017
(51)International Patent Classification (IPC): 
G01D 21/00(2006.01)

(54)

FIELD DEVICE AND DETECTOR

FELDVORRICHTUNG UND -DETEKTOR

DISPOSITIF DE TERRAIN ET DÉTECTEUR


(84)Designated Contracting States:
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

(30)Priority: 22.03.2016 JP 2016056791
03.02.2017 JP 2017018961

(43)Date of publication of application:
27.09.2017 Bulletin 2017/39

(73)Proprietor: Yokogawa Electric Corporation
Tokyo 180-8750 (JP)

(72)Inventor:
  • YOSHIDA, Shinnosuke
    Tokyo (JP)

(74)Representative: Henkel & Partner mbB 
Patentanwaltskanzlei, Rechtsanwaltskanzlei Maximiliansplatz 21
80333 München
80333 München (DE)


(56)References cited: : 
EP-A2- 2 187 175
DE-A1-102012 223 706
DE-A1-102009 026 785
DE-A1-102014 009 354
  
      
    Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


    Description

    BACKGROUND


    Technical Field



    [0001] Disclosure of the present application relates generally to a field device and a detector wherein a detector includes a sensor converts a measurement signal into a physical quantity and transmits the physical quantity as digital data to a converter. Disclosure of the present application also relates to a detector in which a detector includes a sensor converts a measurement signal into a physical quantity and outputs the physical quantity as digital data.

    Related Art



    [0002] Conventionally, in a field device in which a detector includes a sensor and a converter for converting a measurement value into a unified instrumentation signal and outputting the unified instrumentation signal are separate, all electric circuits required for calculation are mounted on the converter side, and the converter performs a process of converting a measurement signal which is analog-transmitted from the detector into a physical quantity, converting the physical quantity into a unified instrumentation signal, and outputting the unified instrumentation signal to the outside.

    [0003] In recent years, intelligentization of field devices has been in progress, and a field device referred to as a smart sensor that converts a measurement signal into a measurement value which is a physical quantity on the detector side and transmits the obtained measurement value as digital data to the converter is being put to practical use.

    [0004] FIG. 4 is a block diagram illustrating a configuration example of a conventional smart sensor 500. The smart sensor 500 includes a detector 510 and a converter 520, which are connected by a cable 530.

    [0005] The detector 510 includes a first microprocessor 511, a random access memory (RAM) 512, a read-only memory (ROM) 513, a sensor 514, an amplifier 515, a filter 516, an analog-to-digital (A/D) converter 517, and an internal power source 518. In the example of FIG. 4, measurement systems including a system A and a system B are assumed to be provided, and the sensor 514, the amplifier 515, the filter 516, and the A/D converter 517 are provided in two systems corresponding to the system A and the system B.

    [0006] In each of the systems, an analog measurement signal acquired by the sensor 514 is amplified by the amplifier 515, a required band is extracted by the filter 516, and then the analog measurement signal is converted into a digital form by the A/D converter 517.

    [0007] Then, the first microprocessor 511 performs calculation using the RAM 512 and the ROM 513, thereby converting the digital signal into a measurement value which is a physical quantity and outputting the obtained measurement value as digital data to the converter 520 via the cable 530.

    [0008] The converter 520 includes a second microprocessor 521, a RAM 522, a ROM 523, a 4-20 mA current output circuit 524, and an internal power source 525. The second microprocessor 521 receives the digital data transmitted from the detector 510 and performs predetermined processing on the digital data by using the RAM 522 and the ROM 523. The 4-20 mA current output circuit 524 converts the measurement value into a 4-20 mA direct current which is a unified instrumentation signal and outputs the 4-20 mA direct current to an external device 540.

    [0009] Power is supplied to the smart sensor 500 from the external device 540 via a signal line that outputs the 4-20 mA direct current. The smart sensor 500 uses the supplied power as the internal power source 525 of the converter 120 and also supplies the power to the internal power source 518 of the detector 510 via the cable 530.

    [0010] Japanese Unexamined Patent Application, First Publication No. H10-221132 is an example of the above-described related art.

    [0011] When trouble occurs in the detector 510, there is a need to analyze a measurement signal output from the sensor 514 to find the cause, or the like. Generally, the detector 510 installed on site is often installed in a place that is difficult for an operator to enter or work. Consequently, in such a case, the analysis is performed using the digital data output by the first microprocessor 511.

    [0012] However, because the digital data output by the first microprocessor 511 is a result of the A/D converter 517 discretizing (digitizing) the measurement signal output from the sensor 514 and the first microprocessor 511 converting the discretized measurement signal into a measurement value which is a physical quantity, the digital data is not necessarily suitable for the analysis of the measurement signal.

    [0013] Thus, an objective of the present invention is to facilitate analysis of a measurement signal of a sensor in a field device in which a detector includes a sensor converts a measurement signal into a physical quantity and transmits the physical quantity as digital data to a converter. Another objective of the present invention is to facilitate analysis of a measurement signal of a sensor also in a converter in which a detector includes a sensor converts a measurement signal into a physical quantity and outputs the physical quantity as digital data to the outside.

    [0014] DE 10 2014 009354 A1 discloses a field device implemented to communicate with an external input-output device of a control system so as to transmit a digital signal and an analog signal.

    [0015] DE 10 2012 223706 A1 and DE 10 2009 026785 A1 disclose further background state of the art.

    SUMMARY



    [0016] According to the present invention the above object is achieved by a field device according to claim 1 and a method according to claim 10. The dependent claims are directed to different advantageous aspects of the invention.

    BRIEF DESCRIPTION OF THE DRAWINGS



    [0017] 

    FIG. 1 is a block diagram illustrating a configuration of a smart sensor according to a first embodiment not forming part of the invention.

    FIG. 2 is a block diagram illustrating a modified example of the smart sensor according to a second embodiment not forming part of the invention.

    FIG. 3 is a block diagram illustrating a third embodiment of the smart sensor according to the invention.

    FIG. 4 is a block diagram illustrating a configuration example of a conventional smart sensor.


    DESCRIPTION OF EMBODIMENTS



    [0018] Embodiments of the present invention will be described with reference to the drawings.

    [First embodiment]



    [0019] FIG. 1 is a block diagram illustrating a configuration of a smart sensor 100 according to the present embodiment. The smart sensor 100 includes a detector 110 and a converter 120. The detector 110 and the converter 120 are connected to each other via a cable 130. The smart sensor 100 is constituted in a form in which the detector 110 and the converter 120 are separated. The smart sensor 100 is a field device in which the detector 110 transmits a measurement value as digital data to the converter 120, and may be a vortex flowmeter, an electromagnetic flowmeter, a Coriolis flowmeter, a differential pressure transmitter, or the like. In the present embodiment, the detector 110 and the converter 120 are installed to be spaced apart from each other. Access to the detector 110 is assumed to not be as easy as access to the converter 120.

    [0020] The detector 110 includes a first microprocessor 111 (first processor), a random access memory (RAM) 112, a read-only memory (ROM) 113, a sensor 114, an amplifier 115, a filter 116, an analog-to-digital (A/D) converter 117, and an internal power source 118. In the example of FIG. 1, the detector 110 includes measurement systems including a system A and a system B. In the detector 110, the sensor 114, the amplifier 115, the filter 116, and the A/D converter 117 are provided in two systems corresponding to the system A and the system B.

    [0021] In each of the systems, an analog measurement signal acquired by the sensor 114 is amplified by the amplifier 115, a required band is extracted by the filter 116, and then the analog measurement signal is converted into a digital form by the A/D converter 117.

    [0022] Then, the first microprocessor 111 performs calculation using the RAM 112 and the ROM 113, thereby converting the digital signal into a measurement value which is a physical quantity and outputting the obtained measurement value as digital data to the converter 120 via the cable 130.

    [0023] The converter 120 includes a second microprocessor 121 (second processor), a RAM 122, a ROM 123, a 4-20 mA current output circuit 124, an internal power source 125, and a sensor A signal monitoring terminal 126.

    [0024] The second microprocessor 121 receives the digital data transmitted from the detector 110. The second microprocessor 121 performs predetermined processing on the transmitted digital data using the RAM 122 and the ROM 123. The 4-20 mA current output circuit 124 converts the measurement value into a 4-20 mA direct current which is a unified instrumentation signal and outputs the unified instrumentation signal to the external device 140. However, instrumentation signals of other standards may be adopted.

    [0025] Also, an insulation circuit may be provided in a previous stage with respect to the second microprocessor 121. As the isolation circuit, for example, a capacitor, an insulating transformer, a photo coupler, or the like can be used. In this way, even in a field device that requires the earth (ground) of the detector, a feedback current generated inside the device can be prevented from flowing out to the external earth (ground). Thus, the feedback current inside the device can be accurately controlled, and accuracy of a current output of the 4-20 mA current output circuit 124 can be increased. In addition, noise resistance from both the converter 120 and the detector 110 can be improved.

    [0026] Power is supplied to the smart sensor 100 from the external device 140 via a signal line that outputs a 4-20 mA direct current. The smart sensor 100 uses the supplied power as the internal power source 125 of the converter 120 and also supplies the power to the internal power source 118 of the detector 110 via the cable 130. A converter of a four-wire field device such as an electromagnetic flowmeter or a Coriolis flowmeter may receive power from a commercial power source.

    [0027] Further, in the present embodiment, analog data (an analog signal) output from a filter A116a of the system A in the detector 110 is transmitted to the converter 120 via the cable 130. Therefore, the cable 130 includes wires of three systems including a digital data system (digital signal system), an analog signal system, and a power supply system.

    [0028] That is, by being connected to the detector 110 by a signal line for digital communication, the converter 120 can acquire a numerical value by digital data obtained by converting a sensor signal. The numerical value may be assumed to be data obtained by converting a physical quantity corresponding to the sensor signal. Further, the converter 120 is connected to the detector 110 via a signal line for at least one analog signal, separate from the above-mentioned signal line for digital communication. The analog signal is for transmitting at least one sensor acquisition signal from the detector 110 to the converter 120. The converter 120 can monitor sensor signals by the analog signal line.

    [0029] The digital data (digital signal) herein refers to a signal obtained by digitizing a signal, that is processed on the detector 110 and derived from an instantaneous value of a process value or a diagnostic value. The digital signal is, for example, a signal for transmitting such information to the converter 120 by serial communication or parallel communication, or a signal obtained by binarizing (for example, a binary of High or Low) a state such as normality/abnormality of a circuit of the detector 110, and the like. In addition, the digital data is appropriately encoded as necessary and transmitted from the detector 110 to the converter 120 in some cases.

    [0030] Here, the diagnostic value is a value of a state diagnosis of a sensor A114a or a sensor B114b. The diagnostic value is a value that serves as a basis for indicating normality or abnormality of the sensor.

    [0031] Also, the analog signal is a signal that is processed by the detector 110 of various field devices and analogically represents an instantaneous value of a process value or a diagnostic value. An analog signal may be associated with a numerical value represented by a voltage level, for example.

    [0032] For example, in the case of a vortex flowmeter, the analog signal is a signal itself output from the sensor (a signal after a charge amp (amplifier)). Alternatively, the analog signal is a signal passed (filtered) only through a band in which a sensor signal is present. Alternatively, the analog signal is a signal that represents a current value of a frequency indicating a flow rate measured by the vortex flowmeter, such as a pulse signal representing a result of comparison of a sensor signal at a predetermined comparative level after the sensor signal is amplified. Alternatively, the analog signal may be an analog signal related to temperature for correcting the vortex flowmeter (a voltage output from a temperature measurement circuit) or an analog signal related to pressure (a voltage output from a pressure measurement circuit). Further, the above-described various analog signals may be switched in a time division manner and transmitted from the detector 110 to the converter 120.

    [0033] For example, in the case of an electromagnetic flowmeter, the analog signal is a signal itself output from the sensor (signal after the charge amplifier). Alternatively, the analog signal is a signal passed only through a band in which a sensor signal is present. Alternatively, the analog signal may be an analog signal acquired by a diagnosis circuit (an electrode potential signal, an inter-electrode impedance, a signal related to an exciting current).

    [0034] For example, in the case of the Coriolis flowmeter or an ultrasonic flowmeter, the analog signal is the signal itself output from the sensor (signal after charge amplifier). Alternatively, the analog signal is a signal passed only through a band in which a sensor signal is present. Alternatively, the analog signal may be an analog signal acquired by the diagnostic circuit.

    [0035] The analog signal transmitted to the converter 120 can be extracted from the outside of the converter 120 via the sensor A signal monitoring terminal 126. The analog signal may also be received by the second microprocessor 121.

    [0036] The transmitted analog signal can be regarded as a measurement signal of the sensor because the transmitted analog signal is a result of an amplifier A 115a amplifying the measurement signal of the sensor A114a and the amplified measurement signal passing through the filter A116a. Thus, analysis of a measurement signal of the sensor can be facilitated by the analog signal being extracted from the sensor A signal monitoring terminal 126 provided in the converter 120. Also, the operator may perform the analysis by opening a cover of the converter 120, connecting a measurement input unit of an external measurement device to the sensor A signal monitoring terminal 126, and measuring an analog signal.

    [0037] The analog signal transmitted to the converter 120 can be used for purposes other than analyzing a measurement signal of the sensor. For example, a device that has received an analog signal from the sensor A signal monitoring terminal 126 or the second microprocessor 121 that has received an analog signal may calculate a measurement value on the basis of a measurement signal of the analog signal and compare the measurement value with a measurement value of digital data sent from the detector 110. The converter 120 may be constituted to output an alarm when a difference in the physical quantities converted from signals of a digital signal and an analog signal exceeds a predetermined range (e.g., a tolerance range of 1% and the like). The tolerance range is predetermined on the basis of measurement accuracy and the like, for example. In other words, the second microprocessor 121 outputs an alarm when a difference between a measurement value based on the analog signal and a measurement value based on the digital signal exceeds a predetermined amount. The predetermined amount may be a ratio related to a physical quantity obtained as described above. Also, the predetermined amount may be an absolute value of a physical quantity obtained as described above. As a result, diagnosis can be performed by means of dualized signals (the analog signal and the digital signal) having different techniques in safety instrumentation. That is, reliability of a measurement value can be improved or a detection rate of an abnormal operation of the field device can be improved.

    [0038] Also, a device that has received an analog signal from the sensor A signal monitoring terminal 126 or the second microprocessor 121 that has received an analog signal may compare a measurement value based on a measurement signal of the analog signal with a measurement value of digital data and determine the soundness of a transmitted digital signal (whether the digital signal is sound). For example, a measurement value indicating a digital signal may include a large error due to external noise, etc. However, by determining the soundness as described above, unsound events such as noise can be detected.

    [0039] Here, to ensure simultaneity of comparison between the analog signal and the digital signal, an acquisition timing of the digital signal is matched with an acquisition timing of the analog signal at the converter 120. For example, when the digital signal represents data from one calculation cycle before, the analog signal is sampled and stored to also be data from one calculation cycle before. For this, a delay circuit is appropriately provided or a memory for storing data is provided.

    [0040] Alternatively, the analog signal and the digital signal may also be compared using integrated values during a time in which a calculation cycle is negligible. That is, a period for taking the integrated values is made to be sufficiently longer than the calculation cycle. In this case, the calculation cycle does not need to be adjusted, and the realization means becomes simpler.

    [0041] When a calculated measurement value does not match a measurement value of transmitted digital data, for example, degradation of the cable 130 may be diagnosed as the cause when the mismatch is permanent, and airborne noise may be diagnosed as the cause when the mismatch is temporary.

    [0042] Also, periodic noise caused by the surrounding environment such as piping vibration and a commercial power source can be detected by performing frequency analysis through a fast Fourier transform (FFT) or the like on an analog signal input from the sensor A signal monitoring terminal 126. Specifically, for example, this can be realized by performing frequency analysis of an analog signal read from the sensor A signal monitoring terminal 126 by the second microprocessor 121. Also, a behavior of an object to be detected can be sensed by performing various analysis processes other than the frequency analysis.

    [0043] The present embodiment is not limited to the embodiment described above, and various modifications can be made thereto. For example, although the measurement signal of the sensor of the system A is transmitted as the analog signal to the converter 120 in the above-described embodiment, a measurement signal of a sensor of another system may be transmitted to the converter 120 as an analog signal, and a measurement signal of a sensor may be transmitted as an analog signal to the converter 120 for the entire system.

    [Second embodiment]



    [0044] FIG. 2 is a block diagram illustrating a configuration of a smart sensor 200 according to the present embodiment. The smart sensor 200 includes a detector 210 and a converter 220, which are connected via the cable 130. As a feature of the present embodiment, the detector 210 includes a selector 119. That is, by having the selector 119, the detector 210 may switch between output data of the filter A116a and output data of a filter B116b and transmit data to a sensor signal monitoring terminal 127 provided in the converter 120.

    [0045] For the switching operation of the selector 119, the second microprocessor 121 may give a switching instruction to the first microprocessor 11 1 so that the first microprocessor 111 performs switching control.

    [Third embodiment]



    [0046] FIG. 3 is a block diagram illustrating a configuration of a smart sensor 300 according to the invention. The smart sensor 300 includes a detector 310 and a converter 320, which are connected via the cable 130. In the present embodiment, as illustrated, the first microprocessor 111 selects one of digital sensor measurement signals input from an A/D converter A117a and an A/D converter B 117b, converts the selected digital sensor measurement signal into an analog signal by a digital-to-analog (D/A) converter 151, and transmits the analog signal to the sensor signal monitoring terminal 127 provided in the converter 120.

    [0047] The first to third embodiments have been described above. Also, although two A/D converters are provided in the detectors of FIGS. 1, 2 and 3 (110, 210 and 310, respectively), only one A/D converter may be provided therein, and an analog signal from the filter A116a and the filter B116b may be selectively input using a multiplexer (not illustrated). That is, in this case, the detector transmits a digital signal, which is converted on the basis of any one of a plurality of analog signals, to the converter.

    [0048] Also, a sensor measurement signal transmitted from the detector 110 (or 210, 310) to the converter 120 (or 220, 320) may be converted into a predetermined general format and transmitted. For example, by converting a sensor measurement signal into a voltage signal of 1-5 V, a general-purpose device for extracting an analog signal from the sensor A signal monitoring terminal 126 and performing analysis of the analog signal can be used.

    [0049] The functions of the first microprocessor 111 illustrated in FIGS. 1, 2, and 3 are processes based on commands to acquire an A/D conversion value, calculate an A/D conversion value, perform data transmission of the values to the second microprocessor 121 (serial communication or parallel communication), and perform data transmission from the second microprocessor 121 (serial communication or parallel communication). The functions can be realized by an application-specific integrated circuit (ASIC) (gate array) as well as by the microprocessor. When the functions are realized by the ASIC, the ASIC requires to have only the functions listed above. Thus, compared to the case in which the functions are realized by the microprocessor, the amount of memory and peripherals (timers, serial communication, and general input/output (I/O)) being used can be reduced. In this way, the present embodiment or the modified examples thereof can be realized with lower power consumption, lower cost, or smaller area.

    [0050] Also, although power is supplied from the external device 140 in each of the smart sensors 100, 200, and 300, a modified example thereof may be as follows. That is, in each of the detectors 110, 210, and 310, the internal power source 118 functions as a power source without power being supplied from the converters 120, 220, and 320. In this way, a detector that outputs a signal to an external device may have a configuration that does not require a converter. In other words, the detector in this example includes a sensor for acquiring a measurement signal, an A/D converter for converting an analog signal based on the measurement signal into a digital form, and a first processor for converting the digitally converted measurement signal into a measurement value and outputting the measurement value as a digital signal. The detector outputs the analog signal together with the digital signal to the outside.

    [0051] Each element for the field device described above can be implemented by hardware with or without software. In some cases, the field device may be implemented by one or more hardware processors and one or more software components wherein the one or more software components are to be executed by the one or more hardware processors to implement each element for the field device. In some other cases, the field device may be implemented by a system of circuits or circuitry configured to perform each operation of each element for the field device.

    [0052] While preferred embodiments of the invention have been described and illustrated above, it should be understood that these are exemplary of the invention and are not to be considered as limiting. Accordingly, the invention is not to be considered as being limited by the foregoing description, and is only limited by the scope of the appended claims.


    Claims

    1. A field device comprising:

    a detector (310) comprising:

    a sensor (114) configured to acquire an analog measurement signal;

    an analog-to-digital converter (117) configured to convert the analog measurement signal to a digital signal; and

    a first processor (111) configured to convert the digital signal into a measurement value to generate a digital signal representing at least the measurement value;

    a converter (320) configured to convert the digital signal representing at least the measurement value into an instrumentation signal to output the instrumentation signal, the converter (120) comprising a second processor (121);

    wherein the sensor (114) comprises a first sensor (114a) configured to acquire a first analog measurement signal and a second sensor (114b) configured to acquire a second analog measurement signal,

    wherein the analog-to-digital converter (117) comprises a first analog-to-digital converter (117a) configured to convert the first analog measurement signal to a first digital signal and a second analog-to-digital converter (117b) configured to convert the second analog measurement signal to a second digital signal,

    wherein the first processor (111) is configured to perform a calculation using the first digital signal converted by the first analog-to-digital converter (117a) and the second digital signal converted by the second analog-to-digital converter (117b) to convert the digital signal into the measurement value,

    wherein the detector (310) further comprises a digital-to-analog converter (151) configured to convert a digital signal obtained by the calculation of the first processor (111) into an analog signal, and

    wherein the detector (310) is configured to transmit the digital signal representing at least the measurement value generated by the first processor (111) together with the analog signal converted by the digital-to-analog converter (151) to the converter (310).


     
    2. The field device according to Claim 1, wherein the converter (320) comprises a monitoring terminal for measuring the analog measurement signal.
     
    3. The field device according to any one of Claims 1 or 2, wherein

    the second processor (320) is configured to calculate a measurement value from the analog measurement signal transmitted from the detector (310), and

    that the second processor (121) is configured to compare the measurement value from the analog measurement signal with the measurement value from the digital signal representing at least the measurement value.


     
    4. The field device according to Claim 3, wherein
    the second processor (121) is configured to generate an alarm in case that a difference between the measurement value from the analog measurement signal and the measurement value from the digital signal representing at least the measurement value exceeds a predefined threshold.
     
    5. The field device according to Claim 3 or 4, wherein
    the second processor (121) is configured to determine soundness of the digital signal based on a degree of identity as a result of comparing the measurement value from the analog measurement signal with the measurement value from the digital signal representing at least the measurement value.
     
    6. The field device according to any one of Claims 1 to 5, wherein
    the second processor (121) is configured to process the digital signal representing at least the measurement value transmitted from the detector (310).
     
    7. The field device according to Claim 6, wherein
    the second processor (121) is configured to convert the digital signal representing at least the measurement value, and:
    the converter (320) further comprises an isolation circuit disposed on a previous stage with respect to the second processor (121).
     
    8. The field device according to any one of Claims 1 to 7, wherein
    the detector (310) is configured to transmit, to the second processor (121), the analog measurement signal and the digital signal representing at least the measurement value to cause the second processor (121) to receive the analog measurement signal and the digital signal representing at least the measurement value at the same timing.
     
    9. The field device according to any one of Claims 1 to 8, wherein
    the second processor (121) is configured to calculate a measurement value from the analog measurement signal transmitted; and to compare an integrated value of measurement values from the analog measurement signals with an integrated value of the measurement values from the digital signals representing the measurement values.
     
    10. A method comprising:

    acquiring, by a sensor (114) of a detector (310), an analog measurement signal;

    converting, by an analog-to-digital converter (117) of the detector (310), the analog measurement signal to a digital signal;

    converting, by a first processor (111) of the detector (310), the digital signal into a measurement value to generate a digital signal representing at least the measurement value;

    converting, by a second processor (121) of a converter (320), digital signal representing at least the measurement value into an instrumentation signal to output the instrumentation signal,

    wherein the sensor (114) comprises a first sensor (114a) configured to acquire a first analog measurement signal and a second sensor (114b) configured to acquire a second analog measurement signal,

    wherein the analog-to-digital converter (117) comprises a first analog-to-digital converter (117a) configured to convert the first analog measurement signal to a first digital signal and a second analog-to-digital converter (117b) configured to convert the second analog measurement signal to a second digital signal, and

    wherein the method further comprises:

    performing, by the first processor (111), a calculation to the first digital signal converted by the first analog-to-digital converter (117a) and the second digital signal converted by the second analog-to-digital converter (117b) to convert the digital signal into the measurement value;

    converting, by a digital-to-analog converter (151) of the detector (320), a digital signal obtained by the calculation of the first processor (111) into an analog signal; and

    transmitting by the detector (310) the digital signal representing at least the measurement value generated by the first processor (111) together with the analog signal converted by the digital-to-analog converter (151) to the convert (320).


     
    11. The method according to Claim 10, further comprising:

    calculating, by the second processor (121), a measurement value from the analog measurement signal transmitted; and

    comparing, by the second processor (121), the measurement value from the analog measurement signal with the measurement value from the digital signal representing at least the measurement value.


     
    12. The method according to Claim 10 or 11, further comprising:
    determining, by the second processor (121), soundness of the digital signal based on a degree of identity as a result of comparing the measurement value from the analog measurement signal with the measurement value from the digital signal representing at least the measurement value.
     


    Ansprüche

    1. Ein Feldgerät, aufweisend:

    einen Detektor (310), aufweisend:

    einen Sensor (114), der konfiguriert ist, um ein analoges Messsignal zu akquirieren;

    einen Analog-Digital-Wandler (117), der konfiguriert ist, um das analoge Messsignal in ein digitales Signal umzuwandeln; und

    einen ersten Prozessor (111), der konfiguriert ist, um das digitale Signal in einen Messwert umzuwandeln, um ein digitales Signal zu erzeugen, das mindestens den Messwert repräsentiert;

    einen Wandler (320), der konfiguriert ist, um das digitale Signal, das mindestens den Messwert repräsentiert, in ein Instrumentierungssignal umzuwandeln, um das Instrumentierungssignal auszugeben, wobei der Wandler (120) einen zweiten Prozessor (121) aufweist;

    wobei der Sensor (114) einen ersten Sensor (114a), der konfiguriert ist, um ein erstes analoges Messsignal zu akquirieren, und einen zweiten Sensor (114b) aufweist, der konfiguriert ist, um ein zweites analoges Messsignal zu akquirieren,

    wobei der Analog-Digital-Wandler (117) einen ersten Analog-Digital-Wandler (117a), der konfiguriert ist, um das erste analoge Messsignal in ein erstes digitales Signal umzuwandeln, und einen zweiten Analog-Digital-Wandler (117b) aufweist, der konfiguriert ist, um das zweite analoge Messsignal in ein zweites digitales Signal umzuwandeln,

    wobei der erste Prozessor (111) konfiguriert ist, um eine Berechnung unter Verwendung des ersten digitalen Signals, das durch den ersten Analog-Digital-Wandler (117a) umgewandelt wird, und des zweiten digitalen Signals, das durch den zweiten Analog-Digital-Wandler (117b) umgewandelt wird, durchzuführen, um das digitale Signal in den Messwert umzuwandeln,

    wobei der Detektor (310) ferner einen Digital-Analog-Wandler (151) aufweist, der konfiguriert ist, um ein durch die Berechnung des ersten Prozessors (111) erhaltenes digitales Signal in ein analoges Signal umzuwandeln, und

    wobei der Detektor (310) konfiguriert ist, um das digitale Signal, das mindestens den von dem ersten Prozessor (111) erzeugten Messwert repräsentiert, zusammen mit dem von dem Digital-Analog-Wandler (151) umgewandelten analogen Signal an den Wandler (310) zu übertragen.


     
    2. Das Feldgerät nach Anspruch 1, wobei der Wandler (320) einen Überwachungsanschluss zur Messung des analogen Messsignals aufweist.
     
    3. Das Feldgerät nach einem der Ansprüche 1 oder 2, wobei
    der zweite Prozessor (121) konfiguriert ist, um einen Messwert aus dem von dem Detektor (310) übertragenen analogen Messsignal zu berechnen, und
    der zweite Prozessor (121) konfiguriert ist, um den Messwert aus dem analogen Messsignal mit dem Messwert aus dem digitalen Signal zu vergleichen, das mindestens den Messwert repräsentiert.
     
    4. Das Feldgerät nach Anspruch 3, wobei
    der zweite Prozessor (121) konfiguriert ist, um einen Alarm zu erzeugen, falls eine Differenz zwischen dem Messwert aus dem analogen Messsignal und dem Messwert aus dem digitalen Signal, das mindestens den Messwert repräsentiert, einen vordefinierten Schwellenwert überschreitet.
     
    5. Das Feldgerät nach Anspruch 3 oder 4, wobei
    der zweite Prozessor (121) konfiguriert ist, um die Tauglichkeit des digitalen Signals auf der Grundlage eines Identitätsgrades als Ergebnis des Vergleichs des Messwerts aus dem analogen Messsignal mit dem Messwert aus dem digitalen Signal zu bestimmen, das mindestens den Messwert repräsentiert.
     
    6. Das Feldgerät nach einem der Ansprüche 1 bis 5, wobei
    der zweite Prozessor (121) konfiguriert ist, um das digitale Signal zu verarbeiten, das mindestens den von dem Detektor (310) übertragenen Messwert repräsentiert.
     
    7. Das Feldgerät nach Anspruch 6, wobei
    der zweite Prozessor (121) konfiguriert ist, um das digitale Signal, das mindestens den Messwert repräsentiert, umzuwandeln, und
    der Wandler (320) ferner eine Isolierschaltung aufweist, die auf einer vorhergehenden Stufe in Bezug auf den zweiten Prozessor (121) angeordnet ist.
     
    8. Das Feldgerät nach einem der Ansprüche 1 bis 7, wobei
    der Detektor (310) konfiguriert ist, um an den zweiten Prozessor (121) das analoge Messsignal und das digitale Signal, das mindestens den Messwert repräsentiert, zu übertragen, um den zweiten Prozessor (121) zu veranlassen, das analoge Messsignal und das digitale Signal, das mindestens den Messwert repräsentiert, zum gleichen Zeitpunkt zu empfangen.
     
    9. Das Feldgerät nach einem der Ansprüche 1 bis 8, wobei
    der zweite Prozessor (121) konfiguriert ist, um einen Messwert aus dem übertragenen analogen Messsignal zu berechnen und einen integrierten Wert der Messwerte aus den analogen Messsignalen mit einem integrierten Wert der Messwerte aus den digitalen Signalen, die die Messwerte repräsentieren, zu vergleichen.
     
    10. Ein Verfahren, aufweisend:

    Akquirieren eines analogen Messsignals durch einen Sensor (114) eines Detektors (310);

    Umwandeln des analogen Messsignals durch einen Analog-Digital-Wandler (117) des Detektors (310) in ein digitales Signal;

    Umwandeln des digitalen Signals durch einen ersten Prozessor (111) des Detektors (310) in einen Messwert, um ein digitales Signal zu erzeugen, das mindestens den Messwert repräsentiert;

    Umwandeln eines digitalen Signals, das mindestens den Messwert repräsentiert, durch einen zweiten Prozessor (121) eines Wandlers (320) in ein Instrumentierungssignal, um das Instrumentierungssignal auszugeben,

    wobei der Sensor (114) einen ersten Sensor (114a), der konfiguriert ist, um ein erstes analoges Messsignal zu akquirieren, und einen zweiten Sensor (114b) aufweist, der konfiguriert ist, um ein zweites analoges Messsignal zu akquirieren,

    wobei der Analog-Digital-Wandler (117) einen ersten Analog-Digital-Wandler (117a), der konfiguriert ist, um das erste analoge Messsignal in ein erstes digitales Signal umzuwandeln, und einen zweiten Analog-Digital-Wandler (117b) aufweist, der konfiguriert ist, um das zweite analoge Messsignal in ein zweites digitales Signal umzuwandeln, und

    wobei das Verfahren ferner aufweist:

    Durchführen einer Berechnung durch den ersten Prozessor (111) bezüglich des ersten digitalen Signals, das durch den ersten Analog-Digital-Wandler (117a) umgewandelt wurde, und des zweiten digitalen Signals, das durch den zweiten Analog-Digital-Wandler (117b) umgewandelt wurde, um das digitale Signal in den Messwert umzuwandeln;

    Umwandeln eines durch die Berechnung des ersten Prozessors (111) erhaltenen digitalen Signals durch einen Digital-Analog-Wandler (151) des Detektors (310) in ein analoges Signal; und

    Übertragen des digitalen Signals, das mindestens den von dem ersten Prozessor (111) erzeugten Messwert repräsentiert, zusammen mit dem von dem Digital-Analog-Wandler (151) umgewandelten analogen Signal durch den Detektor (310) an den Wandler (320).


     
    11. Das Verfahren nach Anspruch 10, ferner aufweisend:

    Berechnen eines Messwerts aus dem übertragenen analogen Messsignal durch den zweiten Prozessor (121); und

    Vergleichen des Messwerts aus dem analogen Messsignal mit dem Messwert aus dem digitalen Signal, das mindestens den Messwert repräsentiert, durch den zweiten Prozessor (121).


     
    12. Das Verfahren nach Anspruch 10 oder 11, ferner aufweisend:
    Bestimmen der Tauglichkeit des digitalen Signals durch den zweiten Prozessor (121) auf der Grundlage eines Identitätsgrades als Ergebnis des Vergleichs des Messwerts aus dem analogen Messsignal mit dem Messwert aus dem digitalen Signal, das mindestens den Messwert repräsentiert.
     


    Revendications

    1. Dispositif de terrain, comprenant :

    un détecteur (310) comprenant :

    un capteur (114) configuré de manière à acquérir un signal de mesure analogique ;

    un convertisseur analogique-numérique (117) configuré de manière à convertir le signal de mesure analogique en un signal numérique ; et

    un premier processeur (111) configuré de manière à convertir le signal numérique en une valeur de mesure en vue de générer un signal numérique représentant au moins la valeur de mesure ;

    un convertisseur (320) configuré de manière à convertir le signal numérique représentant au moins la valeur de mesure, en un signal d'instrumentation, en vue de fournir en sortie le signal d'instrumentation, le convertisseur (120) comprenant un second processeur (121) ;

    dans lequel le capteur (114) comprend un premier capteur (114a) configuré de manière à acquérir un premier signal de mesure analogique, et un second capteur (114b) configuré de manière à acquérir un second signal de mesure analogique ;

    dans lequel le convertisseur analogique-numérique (117) comprend un premier convertisseur analogique-numérique (117a) configuré de manière à convertir le premier signal de mesure analogique en un premier signal numérique, et un second convertisseur analogique-numérique (117b) configuré de manière à convertir le second signal de mesure analogique en un second signal numérique ;

    dans lequel le premier processeur (111) est configuré de manière à mettre en œuvre un calcul en utilisant le premier signal numérique converti par le premier convertisseur analogique-numérique (117a), et le second signal numérique converti par le second convertisseur analogique-numérique (117b), en vue de convertir le signal numérique en la valeur de mesure ;

    dans lequel le détecteur (310) comprend en outre un convertisseur numérique-analogique (151) configuré de manière à convertir un signal numérique obtenu par le calcul du premier processeur (111), en un signal analogique ; et

    dans lequel le détecteur (310) est configuré de manière à transmettre le signal numérique représentant au moins la valeur de mesure générée par le premier processeur (111), conjointement avec le signal analogique converti par le convertisseur numérique-analogique (151), au convertisseur (310).


     
    2. Dispositif de terrain selon la revendication 1, dans lequel le convertisseur (320) comprend un terminal de surveillance pour mesurer le signal de mesure analogique.
     
    3. Dispositif de terrain selon l'une quelconque des revendications 1 et 2, dans lequel :

    le second processeur (121) est configuré de manière à calculer une valeur de mesure à partir du signal de mesure analogique transmis par le détecteur (310) ; et

    le second processeur (121) est configuré de manière à comparer la valeur de mesure en provenance du signal de mesure analogique à la valeur de mesure en provenance du signal numérique représentant au moins la valeur de mesure.


     
    4. Dispositif de terrain selon la revendication 3, dans lequel :
    le second processeur (121) est configuré de manière à générer une alarme dans le cas où une différence entre la valeur de mesure en provenance du signal de mesure analogique et la valeur de mesure en provenance du signal numérique représentant au moins la valeur de mesure dépasse un seuil prédéfini.
     
    5. Dispositif de terrain selon la revendication 3 ou 4, dans lequel :
    le second processeur (121) est configuré de manière à déterminer une robustesse du signal numérique sur la base d'un degré d'identité, en conséquence de la comparaison de la valeur de mesure en provenance du signal de mesure analogique à la valeur de mesure en provenance du signal numérique représentant au moins la valeur de mesure.
     
    6. Dispositif de terrain selon l'une quelconque des revendications 1 à 5, dans lequel :
    le second processeur (121) est configuré de manière à traiter le signal numérique représentant au moins la valeur de mesure transmise par le détecteur (310).
     
    7. Dispositif de terrain selon la revendication 6, dans lequel :

    le second processeur (121) est configuré de manière à convertir le signal numérique représentant au moins la valeur de mesure ; et

    le convertisseur (320) comprend en outre un circuit d'isolation disposé sur un étage précédent par rapport au second processeur (121).


     
    8. Dispositif de terrain selon l'une quelconque des revendications 1 à 7, dans lequel :
    le détecteur (310) est configuré de manière à transmettre, au second processeur (121), le signal de mesure analogique et le signal numérique représentant au moins la valeur de mesure, en vue d'amener le second processeur (121) à recevoir, simultanément, le signal de mesure analogique et le signal numérique représentant au moins la valeur de mesure.
     
    9. Dispositif de terrain selon l'une quelconque des revendications 1 à 8, dans lequel :
    le second processeur (121) est configuré de manière à calculer une valeur de mesure à partir du signal de mesure analogique transmis, et à comparer une valeur intégrée de valeurs de mesure provenant des signaux de mesure analogiques, à une valeur intégrée des valeurs de mesure provenant des signaux numériques représentant les valeurs de mesure.
     
    10. Procédé comprenant les étapes ci-dessous consistant à :

    acquérir, par le biais d'un capteur (114) d'un détecteur (310), un signal de mesure analogique ;

    convertir, par le biais d'un convertisseur analogique-numérique (117) du détecteur (310), le signal de mesure analogique en un signal numérique ;

    convertir, par le biais d'un premier processeur (111) du détecteur (310), le signal numérique, en une valeur de mesure en vue de générer un signal numérique représentant au moins la valeur de mesure ;

    convertir, par le biais d'un second processeur (121) d'un convertisseur (320), un signal numérique représentant au moins la valeur de mesure, en un signal d'instrumentation, en vue de fournir en sortie le signal d'instrumentation ;

    dans lequel le capteur (114) comprend un premier capteur (114a) configuré de manière à acquérir un premier signal de mesure analogique, et un second capteur (114b) configuré de manière à acquérir un second signal de mesure analogique ;

    dans lequel le convertisseur analogique-numérique (117) comprend un premier convertisseur analogique-numérique (117a) configuré de manière à convertir le premier signal de mesure analogique en un premier signal numérique, et un second convertisseur analogique-numérique (117b) configuré de manière à convertir le second signal de mesure analogique en un second signal numérique ; et

    dans lequel le procédé comprend en outre les étapes ci-dessous consistant à :

    mettre en œuvre, par le biais du premier processeur (111), un calcul sur le premier signal numérique converti par le premier convertisseur analogique-numérique (117a), et sur le second signal numérique converti par le second convertisseur analogique-numérique (117b), en vue de convertir le signal numérique en la valeur de mesure ;

    convertir, par le biais d'un convertisseur numérique-analogique (151) du détecteur (310), un signal numérique obtenu par le calcul du premier processeur (111), en un signal analogique ; et

    transmettre, par le biais du détecteur (310), le signal numérique représentant au moins la valeur de mesure, généré par le premier processeur (111), conjointement avec le signal analogique converti par le convertisseur numérique-analogique (151), au convertisseur (320).


     
    11. Procédé selon la revendication 10, comprenant en outre les étapes ci-dessous consistant à :

    calculer, par le biais du second processeur (121), une valeur de mesure à partir du signal de mesure analogique transmis ; et

    comparer, par le biais du second processeur (121), la valeur de mesure en provenance du signal de mesure analogique à la valeur de mesure en provenance du signal numérique représentant au moins la valeur de mesure.


     
    12. Procédé selon la revendication 10 ou 11, comprenant en outre l'étape ci-dessous consistant à :
    déterminer, par le biais du second processeur (121), une robustesse du signal numérique, sur la base d'un degré d'identité, en conséquence de la comparaison de la valeur de mesure en provenance du signal de mesure analogique, à la valeur de mesure en provenance du signal numérique représentant au moins la valeur de mesure.
     




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    Cited references

    REFERENCES CITED IN THE DESCRIPTION



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    Patent documents cited in the description