EP3785087A1

EP3785087A1 - Plug-in radio module for automation engineering

Info

Publication number: EP3785087A1
Application number: EP19719790.8A
Authority: EP
Inventors: Harald SCHÄUBLE; Patrice GROSPERRIN
Original assignee: Endress and Hauser SE and Co KG
Current assignee: Endress and Hauser SE and Co KG
Priority date: 2018-04-26
Filing date: 2019-04-17
Publication date: 2021-03-03
Also published as: DE102018110101A1; WO2019206768A1; US20210067192A1; CN111989627A; US11588511B2

Abstract

Plug-in radio module for automation engineering for wireless data transmission, having at least a wired interface (7) for connecting to a corresponding wired field device interface (5) of a field device (1) and radio module electronics (8) having a radio antenna (9), wherein the radio module electronics (8) are configured to use the wired interfaces (5, 7) to query at least one current value (I) of the field device (1) and to use the current value (I) to adapt a paging interval (3a) and/or a radio data width (3b) for the wireless data transmission as appropriate, so that the radio module electronics (8) perform an adapted-power mode of operation in which the wireless data transmission is matched to the power (P) currently made available to the field device (1).

Description

Plug-in radio module of automation technology

The invention relates to a system of automation technology, an attachable radio module of automation technology and a method for wireless

Data transmission between a mobile operating unit and a radio module connected to the field device.

In automation technology, in particular in process automation technology, field devices are often used which serve for the determination, optimization and / or influencing of process variables. Sensors, such as level gauges, flowmeters, pressure and temperature gauges, conductivity meters, etc., are used to record process variables, which record the corresponding process variables level, flow, pressure, temperature and conductivity. To influence process variables are actuators, such as valves or pumps, via which the flow of a liquid in a pipe section or the level in a container can be changed. In principle, field devices are all devices that are used close to the process and that provide or process process-relevant information. In the context of the invention, field devices are thus also understood as remote I / Os (electrical interfaces), radio adapters or in general devices which are arranged on the field level.

A variety of such field devices is manufactured and sold by the company Endress + Hauser.

At present, two-wire field devices which are connected via a two-wire line to a higher-order unit, for example a control unit SPS, are still common in a large number of existing automation systems. The two-wire field devices are designed in such a way that the measured values or control values as the main process variable communicate via the two-wire line or the two-wire cable in the form of a 4-20 mA signal, i. be transmitted. In addition to the primary function, namely the generation of measured values, modern field devices have numerous others

Functionalities that support the efficient and secure management of the process to be monitored. These include u. a. such functions as the self-monitoring of the field device, the storage of measured values, the generation of control signals for actuators, etc ..

The processes observed by means of the field devices are subject to constant modification, both with regard to the structural design of the plants and with regard to the time sequences of individual process steps. In a similar way are the

Field devices to adapt to the changing process conditions and continue to develop. This extends on the one hand to the transducers, on the other hand, but especially on the implemented functions, such. As the control of the transducer, the evaluation of the measurement signals or the presentation of the measurement results as well as the communication with the parent unit.

Due to the two-wire line, the field devices are usually in terms of

Limited voltage and power supply, this applies in particular

Explosive areas.

Because the power consumption is severely limited, such devices are also referred to as low-power field devices. Due to the limited power available to the field device, power for individual components of the field device or components attached to the field device for short-term operation is also severely limited. An example of such components connected to the field device is a radio module or radio adapter for wireless data transmission of data.

In order to be able to guarantee a permanent operation of such a radio module, the radio modules are adapted to the field devices so that they never exceed a maximum allocated power requirement, wherein the power requirement is tuned to a minimum power supplied to the field device. Although this offers the advantage that the

Radio module can safely transmit data at any time wirelessly. The disadvantage, however, is that the data is transmitted wirelessly with a comparatively low transmission speed, so as to save correspondingly more power. It is thus an object of the invention to adapt a radio module in such a way to a field device, that the radio module can be both permanently operated safely, and can transmit the data wirelessly with the highest possible transmission speed. The object is achieved by the system of automation technology according to claim 1, the attachable radio module according to claim 3 and the method according to claim 1. 1

The automation system according to the invention comprises:

- A field device with a field device electronics, which is a terminal for

Connecting a two-wire line and a wired field device interface, wherein the field device via the two-wire line, which is connectable to the terminal, at least a minimum operating power is provided;

- An attachable wireless module of automation technology for wireless

Data transmission at least having a wired interface to Connecting to the field device interface of the field device and a

Radio module electronics with a radio antenna, wherein the radio module electronics is adapted to interrogate at least a current value of the field device via the wired interfaces and adjust according to the current value of a radio interval and / or a wireless data width for wireless data transmission, so that the radio module electronics performs a performance-adjusted operating mode, in the the wireless data transmission is adapted to the power currently provided to the field device.

An advantageous embodiment of the system according to the invention further comprises a mobile operating unit, which is set up for wireless data transmission with the radio module.

The pluggable radio module according to the invention of the automation technology for wireless data transmission device comprises at least one wired interface for connection to a corresponding wired

Field device interface of a field device and a radio module electronics with a radio antenna, wherein the radio module electronics is adapted to over the

wired interfaces to interrogate at least a current value of the field device and based on the current value, a radio interval and / or a wireless data width for the wireless data transmission to adapt accordingly so that the radio module electronics performs a performance-adjusted operating mode in which the wireless

Data transmission is adapted to the power currently provided to the field device.

An advantageous embodiment of the radio module or of the system provides that the radio module electronics is furthermore configured to execute a standard operating mode in which the radio interval and / or the wireless data transmission radio data width to a minimum operating power which is at least made available to the field device, is adjusted.

An advantageous embodiment of the radio module or of the system provides that the radio module electronics is further configured to switch between the standard operating mode and the power-adjusted operating mode, wherein the switchover from the standard operating mode to the power-adjusted mode is triggered in particular by an external action of an operator becomes. In particular, the embodiment can provide that the external action requests a request

Radio module for wireless data transmission of an envelope of the field device comprises.

An advantageous embodiment of the radio module or the system provides that the radio module electronics for adjusting the radio interval and / or the radio data width a table or a mathematical function is used which maps a possible power for the radio module for each current value, wherein the

Radio module electronics is further adapted to the radio interval and / or the

Adjust radio data width to a power determined for the requested current value from the table or via the mathematical function.

An advantageous embodiment of the radio module or the system provides that the radio module electronics is further configured to interrogate via the wired interfaces, a terminal voltage applied to a terminal of the field device, and the wireless interval and / or the wireless data width for the wireless

Adapt data transmission based on the requested current value and the clamping voltage.

An advantageous embodiment of the radio module or the system provides that the table or the mathematical function depicts the possible power as a function of the different current values and corresponding terminal voltages.

An advantageous embodiment of the radio module or of the system provides that the radio module electronics is furthermore configured to carry out the wireless data transmission in accordance with one of the following standards or protocols or a variant modified therefrom:

Bluetooth or Bluetooth Low Energy;

- 6 LoWPAN;

- 6TiSCH; or

- Wireless HART.

The invention further relates to a method for wireless data transmission, in particular the wireless transmission of data of an envelope of a field device, between a mobile operating unit and an infected to the field device

Radio module according to one of the previously described embodiments, comprising at least the following steps:

Request of the current value via the wired interface in a field device electronics of the field device by the radio module electronics;

- Adapting the radio interval and / or the radio data width of the radio module at least to the requested current value of the field device;

- Wireless transmission of data, in particular data of the envelope of the field device, with the adjusted radio interval and / or the radio data width between the

Radio module and the mobile control unit. In this case, all portable computing units with a radio interface for wireless data transmission come into consideration as the operating unit. Examples of

Operating units are mobile phones or smartphones, notebooks or tablets.

An advantageous embodiment of the method according to the invention provides that the radio module electronics also interrogate the terminal voltage applied to the terminal of the field device, and wherein the radio module electronics adjusts the radio interval and / or the wireless data width for the wireless data transmission based on the queried current value and the terminal voltage.

An advantageous embodiment of the method according to the invention provides that the radio module electronics also between the standard operating mode and the

power switched mode of operation switches back and forth, wherein the switching from the standard operating mode in the power adjusted mode is triggered by an executed on the mobile control unit external action, in particular a request for transmission of an envelope by an operator.

The invention will be explained in more detail with reference to the following drawing. It shows:

1 shows a schematic representation of a system according to the invention

Automation technology.

Figure 1 shows a schematic representation of the system according to the invention of automation technology. The system has a two-wire field device 1, which comprises a preferably metallic housing 2 in that a field device electronics 4 is arranged. The field device electronics 4 is designed such that these

Connecting terminals 13, via a two-wire line 12 electrically

is connected or can be connected. About the two-wire line 12 is the

Field device electronics 4 and thus the field device 1 connected to a, not separately shown in Fig. 1, higher-level unit to communicate with the higher-level unit data wired. In this case, the measured values are communicated as the main process variable via the two-wire line 12 analogously in the form of a 4-20 mA current signal, in that a corresponding current value of the 4-20 mA current signal is provided by the field device electronics. Other data, which may include, for example, parameters of the field device, are transmitted in the form of a digital two-wire signal, for example according to the HART standard. Furthermore, the field device electronics 4 are also supplied with energy via the two-wire line or the 4-20 mA current signal. For this purpose, the field device electronics in response to a terminal voltage Uk, to the

Terminals, and the 4-20 mA current signal, an operating power to Provided. Usually, the clamping voltage Uk comprises a minimum voltage value of about 10 V, so that a minimum operating power for the

Field device electronics of Lmin = 10V ^* 4mA = 40mW. In principle, however, the terminal voltage may also have a value deviating therefrom, for example a value from the range of 10-30 V.

In order to ensure safe operation of the field device 1, the field device electronics 4 is designed such that these all functions, in particular the detection or placement of measured values, the processing of these and the transmission or setting of a corresponding current value of the 4-20 mA current signal means the minimum

Operating power Pmin can perform. Furthermore, the field device electronics 4 is set up such that part of the minimum operating power is permanently available for an externally connectable radio module 6 or, as it were, this part is used for the

Radio module is "reserved". This provided part of the minimum

Operating power is used to permanently power the radio module with a minimum

Operate radio module operating power.

The system further comprises a radio module 6 for wireless data transmission with a radio module electronics 8 and a wired interface 7. About the

wired interface 7, the wireless module 6 for wired communication is detachably connected in terms of data to a field device interface 5 of the field device 1.

The radio module 6 has a radio channel 9, the radio module electronics 8 being set up to convert the data originating from the field device electronics 4 via the wired interface 5 into data corresponding to the wireless transmission, which data can then be transmitted via the radio antenna 9 and vice versa.

According to the radio module electronics 8 is adapted to a

perform power-adapted operating mode in which a radio interval 3a and / or a wireless data width 3b is adapted to the field device 1 currently provided by the two-wire line 12 power P, so that the radio module at least briefly with a power above the necessary minimum

Radio module operating power is operable. For this purpose, the radio module electronics 8 is set up to query at least the currently set current value I in the field device electronics 4 via the wired interfaces 5, 7 and based on at least the

Current value I to determine a currently available for the radio module maximum possible power, so that the radio interval 3a and / or the wireless data width 3b can be adjusted accordingly. The power-adjusted mode of operation may be configured such that the procedure for adjusting the radio interval 3a and / or the radio data width 3b at regular intervals by the radio module electronics. 8 is carried out so that the adaptation of the radio interval 3a and / or the

Wireless data width 3b to the field device 1 currently available power P dynamically. It goes without saying that in the event that the radio interval and / or the wireless data width is increased due to the available extra power, the wired communication via the wired interface 7 for communicating the data to be transmitted wirelessly, is adjusted accordingly.

With radio interval 3a, the interval between two active transmission or

Reception actions of the radio module 6 to understand and with radio data width 3b the

Number of radio packets transmitted per send or receive actions. Depending on the type of radio technology used, the radio interval or the

Radio data width differently designated. For example, with Bluetooth Low Energy, the wireless interval is referred to as the "connection interval", and the wireless data is referred to as "packets per connection event".

To determine the power available for the radio module 6, a memory 15 of the radio module electronics can have a table in which specific power values for specific current values are stored. Additionally or alternatively, a mathematical function describing the relationship between the current value I and the power can be stored. In addition to querying the current value I, the radio module electronics 6 can also be set up to interrogate the value of the terminal voltage UK in the field device electronics via the wired interfaces 5, 7, so as to enable a more precise determination of the power available to the radio module. It goes without saying that in this case the stored table or the mathematical function is extended by corresponding clamping voltage values Uk.

In addition to the power adjusted mode of operation, the radio module electronics 8 may be further configured to execute a standard operating mode in which the

Radio interval 3a and / or wireless data width 3b is adapted to the field device 1 made available minimum operating power Pmin. In addition, the

Radio module electronics 8 be configured to switch between the standard operating mode and the power-adjusted operating mode or switch. The

Switching can by triggering a specific action, eg. The

Request for transferring a larger amount of data to be initiated. Such an action may, for example, the request for transmission of an envelope 14 of the

Field device 1 on a mobile control unit 10 by an operator 1 1 include.

Alternatively or additionally, however, the external action can also be the request for a general function, such as loading or saving a configuration of the Field device (parameterization), the loading of an event logbook or similar functions.

The request for the transmission of the data can in this case be carried out by the operator 1 1 on the mobile operating unit 10, for example by inputting a corresponding command.

LIST OF REFERENCE NUMBERS

field device

Housing of the field device

a radio interval

b radio data width

Field device electronics

Field device interface

radio module

wired interface of the radio module

Radio module electronics

radio antenna

0 Mobile control unit

1 operator

2 two-wire line

3 terminal

4 Envelope

5 memory

Current value of the field device

minimal operating performance

terminal voltage

Claims

claims

1 . System of automation technology comprising:

a field device (1) with a field device electronics (4), which a

Connecting terminal (13) for connecting a two-wire line (12) and a wired field device interface (5), wherein the field device (1) via the two-wire line (12) which is connectable to the terminal (13), at least a minimum operating power (Pmin) is made available; an attachable radio module (6) of the automation technology for wireless data transmission at least comprising a wired interface (7) for connection to the field device interface (5) of the field device (1) and a radio module electronics (8) with a radio antenna (9), wherein the

Radio module electronics (8) is set up over the wired

Interfaces (5, 7) to interrogate at least one current value (I) of the field device (1) and correspondingly adapt a radio interval (3a) and / or a radio data width (3b) for the wireless data transmission on the basis of the current value (I), so that the radio module electronics (8 ) performs a performance adjusted operation mode in which the wireless data transmission is adapted to the power (P) currently provided to the field device (1).

The system of claim 1, further comprising a mobile control unit (10) adapted for wireless data transmission with the wireless module (6).

3. Plug-in wireless module of automation technology for wireless

Data transmission at least comprising a wired interface (7) for connection to a corresponding wired field device interface (5) of a field device (1) and a radio module electronics (8) with a radio antenna (9), wherein the radio module electronics (8) is adapted to the wired Interfaces (5, 7) to interrogate at least one current value (I) of the field device (1) and correspondingly adapt a radio interval (3a) and / or a radio data width (3b) for the wireless data transmission on the basis of the current value (I), so that the radio module electronics (8 ) performs a performance adjusted mode of operation in which the wireless

Data transmission to the field device (1) currently provided power (P) is adjusted.

4. Radio module or system according to one or more of the preceding claims, wherein the radio module electronics (8) is further adapted to a

Standard operating mode in which the radio interval (3 a) and / or the

Wireless data width (3b) for wireless data transmission to a minimum Operating power (Pmin), which is at least provided to the field device (1) is adjusted.

5. radio module or system according to one or more of the preceding claims, wherein the radio module electronics (8) is further adapted to between the

Standard operating mode and the power-adjusted operating mode to switch back and forth, the switching from the standard operating mode in the

performance-adjusted mode in particular by an external action of an operator (1 1) is triggered.

6. Radio module or system according to the preceding claim, wherein the external action comprises a request to the radio module for wireless data transmission of an envelope (14) of the field device (1).

7. Radio module or system according to one or more of the preceding claims, wherein the radio module electronics (8) for adapting the radio interval (3a) and / or the radio data width (3b) relies on a table or a mathematical function which for each current value in each case one for the radio module (6) maps possible power, the radio module electronics (8) being further adapted to adapt the radio interval and / or the radio data width to a power determined for the requested current value from the table or via the mathematical function.

8. Radio module or system according to one or more of the preceding claims, wherein the radio module electronics (8) is further adapted to, via the wired interfaces (5, 7) a terminal voltage (Uk) connected to a terminal (13) of the field device (1 ) is present, to interrogate and the radio interval (3a) and / or the

Radio data width (3b) for the wireless data transmission on the basis of the requested current value (I) and the terminal voltage (Uk) adapt.

9. Radio module according to claim 7 or 8, wherein the table or the mathematical

Function that maps possible power depending on the various current values and corresponding terminal voltages.

10. Radio module or system according to one or more of the preceding claims, wherein the radio module electronics (8) is further adapted to the wireless

Data transmission according to one of the following standards or protocols or a variant modified therefrom:

Bluetooth or Bluetooth Low Energy;

- 6 LoWPAN;

- 6TiSCH; or

- Wireless HART.

1 1. Method for wireless data transmission, in particular wireless

Transmission of data of an envelope of a field device, between a mobile operating unit and a radio module connected to the field device according to one of claims 3 to 10, comprising at least the following steps:

Request the current value via the wired interface at a

Field device electronics of the field device by the radio module electronics;

Adapting the radio interval and / or the radio data width of the radio module at least to the queried current value of the field device;

Wireless transmission of data, in particular data of the envelope of the field device, with the adapted radio interval and / or the radio data width between the radio module and the mobile operating unit.

12. The method according to the preceding claim, wherein the radio module electronics also the terminal voltage applied to the terminal of the field device, queries and wherein the radio module electronics, the radio interval and / or the wireless data transmission for wireless data transmission based on the queried current value and the

Adjusts clamping voltage.

13. The method of claim 12, wherein the radio module electronics further between the standard operating mode and the power-matched

Operating mode switches back and forth, the switching of the

Standard operating mode in the power-adjusted mode by an executed on the mobile control unit external action, in particular a request for transmission of an envelope, is triggered by an operator.