EP3230699A1

EP3230699A1 - Additional module for a processing and/or automation field device

Info

Publication number: EP3230699A1
Application number: EP15790116.6A
Authority: EP
Inventors: Benjamin MONSE; Kaj Uppenkamp; Wolfgang Brutschin; Izabella SANDOR
Original assignee: Endress and Hauser SE and Co KG
Current assignee: Endress and Hauser SE and Co KG
Priority date: 2014-12-11
Filing date: 2015-11-03
Publication date: 2017-10-18
Also published as: US20180350294A1; CN107003166A; WO2016091480A1; US10692421B2; DE102014118394A1

Abstract

The invention relates to an additional module (10) for a processing and/or automation field device (1), at least comprising a module housing (11), an optical receiving unit (13) which is arranged at least partly within the module housing (11), an electronic module unit (15), and a display/transmission unit (17). The optical receiving unit (13) is designed to wirelessly receive at least one first optical signal (12) from the field device (1) and to convert the at least one first optical signal (12) into at least one first electric signal (14), and the electronic module unit (15) is electrically connected to the receiving unit (13) and to the display/transmission unit (17). The electronic module unit (15) is designed to extract at least one piece of field device information from the at least one first electric signal (14) and to transmit the at least one piece of field information to the display/transmission unit (17), and the display/transmission unit (17) is designed to display the at least one piece of information and/or to transmit the at least one piece of information to at least one external unit (18).

Description

Additional module for a field device of process and / or automation technology

The invention relates to an additional module for a field device of process and / or automation technology to at least display information about a switching state, and / or a parameter and / or diagnostic information and / or to transmit to an external unit.

In process and / or automation technology, many different field devices are used to determine and / or monitor at least one process variable. These are, for example, level gauges,

Flowmeters, pressure and temperature measuring devices, pH redox potential measuring devices, conductivity measuring devices, etc., which record the corresponding process variables level, flow, pressure, temperature, pH or conductivity. A field device typically comprises at least one at least partially and at least temporarily come into contact with the process sensor unit and an electronic unit, which serves for example the signal detection, evaluation and / or - supply. In the context of the present application, field devices are in principle all measuring devices that are used close to the process and that provide or process process-relevant information, including remote I / Os, radio adapters or generally electronic components, which are arranged at the field level. A variety of such field devices is manufactured and sold by the company Endress + Hauser.

Flowmeters are especially Coriolis, ultrasonic, vortex, thermal and / or magnetic inductive flowmeters.

Level gauges are in particular microwave level gauges, ultrasonic level gauges, time domain reflectometric level gauges (TDR), radiometric level gauges, capacitive level gauges, conductive level gauges and / or temperature-sensitive level gauges.

Pressure gauges are in particular absolute, relative or differential pressure devices.

Temperature measuring devices are in particular measuring devices with thermocouples and temperature-dependent resistors.

Point level measuring devices are in particular vibronic point level measuring devices, ultrasonic point level measuring devices and / or capacitive or conductive

Point level measurement devices. Analytical measuring devices are in particular pH sensors, conductivity sensors, oxygen and active oxygen sensors, (spectro) -photometric sensors, and / or

ion-selective electrodes. To display information, operating states, measured values, device parameters or the like, field devices often have at least one display unit, such as a display, or at least one optical and / or acoustic display element. An optical display element is a light-emitting element, in particular an LED. An acoustic element is for example a beeper.

The use of individual optical or acoustic display elements is advantageous in terms of the required space, the power consumption of the respective field device, and / or when using the field device in a potentially explosive environment such as encapsulated field devices that meet the IP69K standard from. However, the bandwidth of the display options is limited to switching states, operating states and / or the presence of malfunctions or malfunctions.

DE102006016381 A1 describes, for example, a field device with a

Display unit comprising at least one LED. DE102008037194A1 describes a field device with a housing, within which a display element is arranged, which comprises for example at least one LED, for displaying the function or a state of a wireless communication unit.

In addition to a firm integration of such a display element in an existing field device and the use of subsequently attachable connector is known. For this purpose M12 connectors are often used in process and / or automation technology. However, these are not able to display malfunctions or malfunctions of the field device on site (ie at the place of assembly in the process). In order to expand the display options of corresponding display modules, the hitherto unpublished German patent application with the file number 102013108532.6 describes a connector with at least four display elements, wherein a first

Display element indicates the operational readiness of the field device, wherein a second and a third display elements signal two antivalent switching outputs of the field device, wherein a fourth display element is a malfunction or malfunction of

Signaled field device, wherein a circuit is provided which is designed so that on the basis of the antivalent switching outputs of the field device detects a malfunction or malfunction of the field device and upon detection of a malfunction or malfunction the fourth

Display element is activated. Corresponding optical display elements are for example also frequently used for vibronic fill level measuring devices, as manufactured and sold by the applicant under the name LIQUIPHANT and SOLIPHANT, and by means of which a predetermined fill level is detected. Such field devices, often referred to as a level switch, are preferably used as dry running protection for pumps or as overfill protection. The respective switching state is output via a switching output of the field device configured according to the type of application. This is also referred to as MIN MAX safety. The on-site information about the respective switching output or switching state of the limit level switch is usually very important for a customer, so that often display elements are integrated with at least one light-emitting element in the field device, which can visualize at least the respective switching state and / or the operating voltage.

However, a disadvantage of such display elements in the form of light-emitting elements is that they are sometimes poorly visible, in particular from a greater distance and / or at a non-perpendicular viewing angle. Therefore, in the previously unpublished German patent application with the file number

1020131 13438.6 describes a display module with a deflecting body, for example a light guide, which deflects the light emerging from at least one light-emitting element.

Based on the cited prior art, the object of the present invention is to expand the functionality of optical display elements in field devices.

This object is achieved by an additional module for a field device of process and / or automation technology, at least comprising a module housing and at least partially disposed within the module housing an optical receiving unit, a module electronics unit, and a display / transmission unit, wherein the optical receiving unit is configured to wirelessly receive at least a first optical signal from the field device, and to convert the at least one first optical signal into at least one first electrical signal, wherein the module electronics unit is electrically connected to the receiving unit and to the display / Transmission unit is connected, wherein the module electronics unit is configured to extract from the at least one first electrical signal at least one field device information, and to pass to the display / transmission unit, and wherein the display / transmission unit is configured to to display the at least one piece of information and / or to transmit it to at least one external unit. For example, field information may include information about a Switching state, and / or an operating state and / or a parameter and / or a diagnostic information. The parameter may be a physical or chemical parameter of the medium and / or the process environment, such as

For example, pressure or temperature, but also act on a sensor parameter. In the case of a vibronic sensor, for example, the mass, the

Dimensions or the resonant frequency of a vibratory unit. In the case of a capacitive level gauge, it may, for example, be the capacitance and / or the dimensions of the probe or additional electrode. The individual parameters and sizes differ depending on the field device used. Optionally, the field device information to be transmitted may also be a measured value. Diagnostic information provides information about a malfunction and / or malfunction within the field device. Again, with the respective diagnostic information between the different types of field devices to

differ. However, the means of the at least one first optical and at least one first electrical signal are always information which is provided within the field device.

The additional module can be used for all field devices which display an optical signal, in particular therefore for field devices with at least one optical display element, in particular with a display element in the form of a

light-emitting element such as an LED. Since many field devices anyway have such in the visual range of the optical spectrum light-emitting display elements, these field devices can be retrofitted with an additional module according to the invention in a simple and cost-effective manner. The receiving unit can in this case be present on the respective display element present in the field device and on the respectively by means of the

Display element displayed optical signal, in particular with respect to its

Intensity and / or wavelength can be adjusted.

The use of an additional module according to the invention thus advantageously requires no interference with the electronic circuits and the arrangement of the respective

Components of the field device. Thus, the integration of an additional module

be carried out according to feedback. This is especially true at

Field devices for use in safety-critical environments, such as in potentially explosive atmospheres, which are advantageous

Safety requirements must meet.

Accordingly, the functionality of a field device can advantageously be extended by the use of an additional module according to the invention. The at least one first optical signal from the field device can either only the anyway by means of the respective Display element displayed field device information, as described above, or moreover contain further field device information, in particular those which are not accessible by means of a simple optical display element containing. These can then be displayed by the display / transmission unit. The field device can also be redesigned without the electronics unit

for example, to extend an interface. In this case, the display transmission unit is configured to transmit information to an external unit. The external unit may be, for example, a field level device or a central plant control unit.

The invention is capable of numerous embodiments, some of which are the subject of the dependent claims.

It is advantageous if the module housing has a plug-in connection unit, by means of which the additional module is detachably fastened on or in the field device.

In a preferred embodiment, the receiving unit has a photodetector, which is designed to receive at least one first optical signal from the

Field device to receive and in the at least one first electrical signal

convert. The photodetector is adapted to the respective display element within the field device, or configured to the first optical signal from

Field device to detect. Important factors to be considered here are, for example, the luminous intensity of the LED, the transmission speed of the first optical signal, which depends inter alia on the particular transmission method chosen, and also the distance between the photodetector and the display element within the field device.

In a further preferred embodiment, the display / transmission unit has an LED, an RGB LED, or a display. In this case, the display / transmission unit merely performs the function of another display unit. In this case, it is possible to restrict oneself to reproducing the information which the display element displays within the field device. In this case, the display / transmission unit may comprise an LED. However, if the display functionality is to be extended by the transmission of further field device information which can not be displayed by the optical display element, for example, an RGB LED or even a display is more suitable since such display elements have a larger number

different device information can represent different. Alternatively, the display / transmission unit in the case of a Bluetooth or

Have radio interface. In this case, the at least one information can be transmitted to at least one external unit. A radio interface may, for example, be a WI_AN module. Thus, the functionality of an existing field device can be extended by a new interface for information transmission. For this, advantageously no changes have to be made within the field device, since the transmission from the field device to the additional module takes place by means of the optical display element of the field device and an optical transmission. This is again advantageous in particular in the event that the field device is used in a potentially explosive environment. The electronics within the field device, which meets stringent safety requirements in this case, need not be changed.

It goes without saying that the display transmission unit also has a display and a transmission interface at the same time.

It is also advantageous if the module electronics unit comprises at least one arithmetic unit. Thus, the at least one first electrical signal, which contains the at least one information of the field device, evaluated and forwarded processed accordingly. Depending on the method used for optical transmission of the at least one field device information by means of the at least one first optical signal, the at least one arithmetic unit must be able to execute certain methods or protocols. For example, it is advantageous for this purpose if the at least one arithmetic unit is designed to execute a protocol, in particular an IrDA- or UART-coded protocol, in order to extract the at least one information from the at least one first optical signal of the field device. This is particularly suitable if the at least one device information is modulated onto the at least one optical signal.

A preferred embodiment includes that the additional module is designed for bidirectional communication with the field device. In this case, the

Receiving unit for receiving the at least one first optical signal within the additional module but not from. Rather, it is advantageous in this case if the additional module has an optical transmitting unit for transmitting at least one second optical signal to the field device. Again, the optical transmission unit of the additional module to be adapted to the respective field device.

For transmission of the at least one first and at least one second optical signal different transmission modes can be selected. If the additional module has to be designed only to display the at least one piece of information, then suffices a pure forwarding of the optical signal of the display element. If further information is to be transmitted, a targeted transmission method must be selected by means of which the at least one field device information can be impressed on the at least one first and possibly the at least one second optical signal. For this purpose, various possibilities are conceivable.

The invention is further achieved by a field device of the process and / or

Automation technology, comprising at least one sensor module and a field device electronics with an optical display unit, and with an additional module according to the invention, wherein the field device electronics is configured to the optical

Display unit to apply at least a second electrical signal, which at least one second electrical signal, the at least one

Field device information includes, wherein the optical display unit is adapted to emit a first optical signal containing the at least one field device information, and wherein the additional module is arranged such that the

Receiving unit facing the optical display unit. This is thus a field device equipped with an additional module, the additional module being fixed in or on the field device. In the arrangement, it should be noted that the at least one first optical signal can hit the receiving unit unhindered. The optical display unit of the field device and the receiving unit of the additional module should therefore be arranged facing each other, in particular such that the receiving unit is within the beam path of the at least one first optical signal. The optical display unit of the field device may be, for example, a display or an optical display element, in particular a light-emitting element, in particular an LED. The LED is preferably designed to display at least one switching state, operating state and / or information about a fault and / or a malfunction by means of at least one emitted optical signal of a wavelength corresponding to the visible range of the light. For example, different information can be displayed in different colors. The color green is often used to indicate the operating status, yellow to indicate switching states and red to indicate a malfunction and / or malfunction.

In a particularly preferred embodiment, the transmission of the at least one field device information takes place by means of a modulation. The optical signal of the optical display element of the field device, the at least one field device information is modulated by the field device electronics. The module electronics unit is then further able to extract the at least one information from the at least one corresponding first electrical signal and to demodulate this signal. It It goes without saying that other optical transmission methods can also be used. In DE 1020121 12160A1, for example, a method for non-visual data transmission by means of a field device with at least one

Display element described. The display element may be configured to visually represent at least one field device information. For data transmission, the non-visual optical signal is preferably transmitted at the same time. For this, however, the field device would have to be equipped with a display element which is designed for non-visual data transmission, which tends to occur rather rarely. In a further preferred embodiment, the additional module is releasably secured within the field device electronics, and in particular attached above the optical display unit. The additional module is thus within a housing of the

Field device electronics arranged. Preferably, however, it is arranged so that any existing safety requirement regarding the protective provisions for use in a potentially explosive atmosphere remain. Such an arrangement is then particularly compact.

It is advantageous if the field device electronics has a window, wherein the display transmission unit is arranged facing the window. In particular, in the event that the display transmission unit has a display, or an LED, this is necessary in order to display the at least one field device information by means of the display / transmission unit.

It is also advantageous if the field device electronics has a field device housing, which allows the use of the field device in a potentially explosive environment.

As already mentioned, the optical display unit in a preferred

Embodiment at least one light-emitting optical display element, in particular an LED for displaying at least one light signal, in particular one

Color signal, on. In this case, it is advantageous if the optical display unit displays at least one switching state and / or an operating state and / or a malfunction and / or malfunction of the field device by means of the light signal, in particular the color signal.

In a further preferred refinement, the field device has a field device receiving unit, in particular a further photodetector, for receiving the at least one second optical signal from the additional module. This measure is For example, to provide bidirectional communication between the

Field device and the additional module.

The invention as well as some advantageous embodiments will be explained in more detail below with reference to FIGS. 1 to 5. It shows:

1 is a schematic diagram of a prior art level gauge comprising an optical display element;

2 shows a schematic sketch of an additional module according to the invention,

3 shows the arrangement of an additional module according to the invention within a field device. FIG. 4 shows a typical transmission signal which is evaluated by means of a suitable protocol within the module electronics unit.

Fig. 5 is a block diagram of a receiving unit in the form of a photodetector, and Fig. 6 shows the arrangement of an additional module according to the invention within a

Field device, suitable for bidirectional communication.

FIG. 1 shows a schematic sketch of a field device 1. By way of example, this is a vibronic level gauge, also level limit switch. The sensor unit 2 comprises a mechanically oscillatable unit 3 in the form of a

Tuning fork. It may be in a generic field device in the

oscillatory unit but also act as a single rod or a membrane. Via a neck tube 3a, the sensor unit 2 is electrically connected to a field device electronics 4 arranged in an encapsulated field device housing 5. The measured value processing and control of the field device 1 is taken over by a central control unit 6. This also controls by means of a second electrical signal 8, an optical display unit 9, within which three light-emitting optical display elements 9a are arranged in the form of LEDs. Furthermore, the field device electronics 4 in the example shown here on an output unit 7, which can be used for example for parameterization of the field device 1. However, the output unit is an optional component.

In order to use an additional module 10 according to the invention, it is necessary that the respective field device 1 has an optical display unit 9 and that the field device Electronics 4 is designed to control this optical display unit 9. For example, for an embodiment of the invention, it should be able to modulate at least one field device information for the optical display unit 9. 2 shows a schematic sketch of an additional module 10 according to the invention. A first optical signal 12 strikes a receiving unit 13 of the additional module, which may be provided, for example, by a photodetector. The receiving unit 13 is arranged together with a module electronics unit 15 and a display / transmission unit 17 in a housing. The at least one first optical signal 12 is converted into at least one first electrical signal 14 by means of the receiving unit 13

converted and forwarded to the at least one arithmetic unit 16 of the module electronics unit 15. There, the at least one first electrical signal is evaluated, which extracts at least one field device information, and transferred to the display / transmission unit. Depending on the embodiment, the display / transmission unit 17 can display the at least one field device information or transmit it to an external unit 18.

A particularly preferred embodiment includes that the additional module 10 can be integrated into an existing field device electronics 4, as shown in Fig. 3. It goes without saying that the housing dimensions of the field device housing 5 then have to be adjusted accordingly. Furthermore, it is expedient to make the cover 19 of the field device housing 5 translucent, that is to say in particular including a window. This window should each be designed so that it is suitable for the

Wavelength of the at least one first optical signal 12 and optionally also for that of the at least one second optical signal 35 (see Fig. 6) is permeable.

The sensor unit 2 of the field device 1 transmits a signal representing a measured value to the field device electronics 4, which in a first step a

Measurement evaluation 20 makes. Often the determined measured value is evaluated by means of a unit for measured value evaluation 21 in order to determine, for example, how a regulation of the transmission signal by means of a switching unit for controlling the measuring instrument 23 is to be carried out. In addition, the field device electronics 4 communicate with an optical display unit 8 to display at least one field device information by means of at least one optical display element. According to the invention, either only the information displayed anyway by means of the optical display element 9 is displayed. Or the optical display element is impressed at least one further field device information, which is contained in the at least one first optical signal 12 of the optical display unit 9 of the field device. The at least one first optical signal 12 is then received by the above the field device electronics 4, but within the field device housing 5, arranged additional module 10 and as explained in Fig. 2, further processed. FIG. 4 shows by way of example a transmission frame for transmitting the at least one

Device information 24 shown. A start bit 25 is followed by an identifier 26 and optional (dashed boxes) the specification of a command and the length.

Subsequently, the transmission of the respective data 29, so the corresponding field device information.

The receiving unit 13 of the additional module 10 may comprise, for example, a photodetector 30. In Fig. 5 is an example of a block diagram of a possible

Receiving unit 13 shown in the form of a photodetector. In the choice of

Photodetector should be based on the light intensity of the optical display element 9a of the

Field device, such as an LED, on the speed of communication between the add-on module 10 and field device 1, and also paid attention to the distance between the receiving unit 12 and the optical display element 9a. The at least one first optical signal 12 impinges on a photodetector 30. Before it is forwarded to the module electronics unit 15, the detected at least one optical signal 12, which is converted into at least a first electrical signal by means of the photodetector 30, is amplified by means of an amplifier 31 and also passes through a comparator 32.

Suitable photodetectors 30 are, for example, phototransistors or photodiodes, which are sensitive to the wavelength of the at least one first optical signal. In this case, the amplifier 31 and the comparator 32 can either be individually integrated and tuned, but also combined variants, in which both components are already optimized to each other, are conceivable, as indicated by the box bordered by dashed lines.

A further embodiment of the present invention is the subject of FIG. 6. As in FIG. 3, an arrangement of an additional module 10 according to the invention within a field device 1 is shown. In contrast to the embodiment according to Figure 3, however, the variant shown in Fig. 6 is suitable for bidirectional communication between the

Field device 1 and the additional module 10. On already explained reference numerals will not be discussed again below. The differences exist, on the one hand, in the integration of an optical field device receiving unit 33. For example, like the receiving unit 13 of the additional module 10, this may include a photoreceiver. In addition, in this case, the additional module 10 has an optical Transmission unit 34, by means of which at least one second optical signal 35 containing at least one information, for example, a set of field device parameters or the like contains. Thus, the field device 1 could for example be parameterized via the additional module 10. It goes without saying that in the case of bidirectional communication wherein the central control unit 6 of the field device 1 is likewise designed to execute a protocol, in particular an IrDA- or UART-coded protocol, in order to obtain the at least one information from the at least one second to extract optical signal 35 of the field device 1.

LIST OF REFERENCES Field device with display unit according to the prior art Sensor unit

Mechanically oscillatable unit

a neck tube

electronics unit

Field device housing

Control unit of the electronic unit

output unit

Second electrical signal

display unit

a Display element in the form of an LED

0 additional module

1 module housing

2 First optical signal

3 receiving unit

4 First electrical signal

5 module electronics unit

6 arithmetic unit of the additional module

7 Display / Transfer Unit

8 Display or transmission of the at least one device information9 Lid of the field device electronics, esp. Transparent cover0 Measured value determination

1 measured value evaluation

2 switch unit to control the meter

3 switching unit for controlling the display unit

4 transmission frame for transmitting the at least one device information5 start bit

6 identifier

7 command

8 length

9 dates

0 photoreceiver

1 amplifier

2 comparator

3 Optical field device receiving unit

4 Optical transmission unit of the additional module Second optical signal

Claims

claims

Additional module (10) for a field device (1) of the process and / or

Automation technology, at least comprising a module housing (11) and at least partially within the module housing (1 1) arranged an optical receiving unit (13), a module electronics unit (15), and a display / transmission unit (17),

wherein the optical receiving unit (13) is configured to wirelessly receive at least a first optical signal (12) from the field device (1), and to convert the at least one first optical signal (12) into at least one first electrical signal (14);

wherein the module electronics unit (15) is electrically connected to the receiving unit (13) and to the display / transmission unit (17),

wherein the module electronics unit (15) is configured to at least one of the at least one first electrical signal (14)

Extract field device information and transfer it to the display / transfer unit (17), and

wherein the display / transmission unit (17) is adapted to display the at least one information and / or to transmit to at least one external unit (18).

Additional module according to claim 1,

wherein the module housing (1 1) has a plug connection unit, by means of which the additional module (10) on or in the field device (1) is releasably attached.

Additional module according to claim 1 or 2,

wherein the receiving unit (13) comprises a photodetector (30) which is configured to receive the at least one first optical signal (12) from the field device (1) and to convert it into the at least one first electrical signal (14).

4. additional module according to at least one of the preceding claims,

wherein the display / transmission unit (17) comprises an LED, an RGB LED, or a display.

5. additional module according to at least one of the preceding claims,

wherein the display / transmission unit (17) has a Bluetooth or

Radio interface has. 6. additional module according to at least one of the preceding claims,

wherein the module electronics unit (15) comprises at least one computing unit (16).

Additional module according to claim 6,

wherein the at least one computing unit (16) is configured to execute a protocol, in particular an IrDA- or UART-coded protocol, in order to extract the at least one information from the at least one first optical signal (12) of the field device (1).

Additional module according to at least one of the preceding claims,

which is designed for bidirectional communication with the field device (1).

9. additional module according to claim 8,

with an optical transmission unit (34) for transmitting at least one second optical signal (35) to the field device (1).

10. Field device (1) of process and / or automation technology, comprising

at least one sensor module (2) and a field device electronics (4) with an optical display unit (9), and with an additional module (19) according to at least one of the preceding claims,

wherein the field device electronics (4) is adapted to the optical

Display unit (9) to act upon at least one second electrical signal (8), which at least one second electrical signal (8) containing at least one field device information,

wherein the optical display unit (9) is configured to receive a first optical signal (12) containing the at least one field device information.

to be emitted (12), and wherein the additional module (10) is arranged such that the receiving unit (13) of the optical display unit (9) faces.

1 1. Field device according to claim 10,

wherein the transmission of the at least one field device information takes place by means of a modulation.

12. Field device according to claim 10 or 1 1,

wherein the additional module (10) detachably mounted within the field device electronics (4), in particular above the optical display unit (9) attached, is.

13. Field device according to at least one of claims 10-12, wherein the field device electronics (4) comprises a window (19), and wherein the display transmission unit (17) facing the window (19) is arranged.

14. Field device according to at least one of claims 10-13,

wherein the field device electronics (4) comprises a field device housing (5), which allows the use of the field device (1) in a potentially explosive environment.

15. Field device according to at least one of claims 10-14,

wherein the optical display unit (9) at least one light-emitting optical

Display element (9a), in particular an LED for displaying at least one light signal, in particular a color signal having.

16. Field device according to at least one of claims 10-14,

wherein the optical display unit (9) at least one switching state and / or an operating state and / or a malfunction and / or malfunction of the

Field device (1) by means of the light signal, in particular the color signal indicates.

17. Field device according to at least one of claims 10-14,

with an optical field device receiving unit (33), in particular another

Photodetector (30) for receiving the at least one second optical signal (25) from the add-on module (10).