METHOD, COMMUNICATION MODULE AND SYSTEM FOR TRANSMITTING DIAGNOSIS DATA OF A FIELD DEVICE IN AN INSTALLATION FOR PROCESS AUTOMATION

Abstract

The present disclosure comprises a method, a communication module, and a system for transmitting diagnosis data of a field device that is connected to a superordinate unit via a communication loop. The communication module is connected to the communication loop in parallel with the field device. The method includes the continual storage of electrical energy in the communication module by a transducer unit within the communication module that captures an electrical and/or physical variable and converts it into electrical energy. The method includes polling the diagnosis data of the field device by the communication module and wireless transmission of the polled diagnosis data to a reception unit by the communication module.

Claims

1-18. (canceled)

19. A method for transmitting diagnosis data of a field device in an installation for process automation, wherein the field device has a communications link to a superordinate unit via a communications loop, comprising: connecting a communications module to the communications loop in parallel with the field device; capturing with a transducer unit in the communications module an electrical and/or physical variable and converting the electrical and/or physical variable into electrical energy; storing the converted electrical energy in an energy storage unit of the communications module up to a predetermined limit value; polling the diagnosis data of the field device using a communication command of the communications module; receiving the diagnosis data of the field device by the communications module via a communication command sent by the field device; and wirelessly transmitting the polled diagnosis data from the communications module to a reception unit as soon as the electrical energy stored in the energy storage unit reaches or exceeds the predetermined limit value and/or if the communications module receives a command for polling or transmitting.

20. The method according to claim 19, wherein the capturing of the electrical and/or physical variable includes the transducer unit converting into electrical energy voltage/current pulses on the communication loop emitted by the superordinate unit or by the field device.

21. The method according to claim 19, wherein the reception unit includes a light source and the transducer unit receives emitted light of the light source and converts the received light into electrical energy.

22. The method according to claim 19, wherein the reception unit includes a radio module which emits an electromagnetic field, and wherein the transducer unit receives at least a part of the emitted electromagnetic field of the radio module and converts the received electromagnetic field into electrical energy.

23. The method according to claim 19, further comprising: sending by the reception unit the polled diagnosis data to a control station of the installation.

24. The method according to claim 19, further comprising: the reception unit supplementing the diagnosis data with additional information including an identification of the field device and/or a time stamp.

25. The method according to claim 19, wherein the step of wirelessly transmitting the polled diagnosis data to the reception unit is performed by the communications module after each polling of the diagnosis data.

26. The method according to claim 19, further comprising: combining the polled diagnosis data in the communications module and transmitting the collected diagnosis data wirelessly to the reception unit at defined time intervals.

27. A communications module, comprising: a transducer unit embodied to convert an electrical and/or a physical variable into electrical energy; an energy storage unit connected with the transducer unit and embodied to store the converted electrical energy; a polling unit configured to poll diagnosis data of a field device; and a transmission unit embodied to wirelessly transmit the polled diagnosis data to a reception unit.

28. The communications module according to claim 27, wherein the communications module includes terminals or insulation displacement terminals embodied to connect the communications module to the cables of a communications loop, wherein the communications loop is not interrupted when the communications module is connected to the communications loop.

29. The communications module according to claim 27, wherein the energy storage unit is formed by a capacitor, a double-layer capacitor, a super capacitor, or a battery.

30. The communications module according to claim 27, wherein the transducer unit is formed by at least one rectifier circuit, including a diode-, detector-, half- or full-rectifier, which is connected to the communications loop.

31. The communications module according to claim 27, wherein the transducer unit includes at least one photodiode or at least one photovoltaic cell.

32. The communications module according to claim 27, wherein the transducer unit includes at least one induction coil or at least one antenna.

33. The communications module according to claim 27, further comprising: a module housing enclosing the transducer unit, the energy storage unit, and the polling unit, wherein the transmission unit is located in the module housing.

34. The communications module according to claim 27, further comprising: a module housing enclosing the transducer unit, the energy storage unit, and the polling unit, wherein the transmission unit has a separate housing and is connected to the communications module via an interface.

35. A system for transmitting diagnosis data from a field device in an installation for process automation, comprising: a superordinate unit in communication with the field device via a communications loop; a communications module connected to the communication loop in parallel with the field device, the communications module including: a transducer unit embodied to capture an electrical and/or physical variable and convert the electrical and/or physical variable into electrical energy; an energy storage unit connected downstream of the transducer unit and embodied to store electrical energy from the transducer unit; a polling unit; and a transmission unit; and a reception unit, wherein the communications module is configured to poll diagnosis data from the field device and transmit the polled diagnosis data to the reception unit via a wireless radio link as soon as a predetermined limit value of stored energy is reached in the energy storage unit of the communications module or when the communications module receives a command for polling or transmitting.

36. The system according to claim 35, wherein the reception unit is designed such that the reception unit has a communications link to a control station of the installation via a wireless or wired network and provides the transmitted diagnosis data to the control system via the network.

Description

[0048] The invention is explained in greater detail with reference to the following figures. Illustrated are:

[0049] FIG. 1: a first variant of an embodiment of the system according to the invention for transmitting diagnosis data from a plurality of field devices in an installation for process automation; and

[0050] FIG. 2: a second variant of an embodiment of the system according to the invention for transmitting diagnosis data from a plurality of field devices in an installation for process automation.

[0051] FIG. 1 shows a first variant of an embodiment of the system according to the invention for transmitting diagnosis data from a plurality of field devices FG1, FG2 in an installation for process automation. Two field devices FG1, FG2 are located in the installation. These field devices FG1, FG2 are, for example, flowmeters. However, they may be any field devices as mentioned in the introductory part of the description by way of example, as well as any number of these field devices FG1, FG2.

[0052] The field devices FG1, FG2 are each connected by means of a communications loop KS1, KS2 to a superordinate unit SPC. This superordinate unit SPC is, especially, a stored program control or a PLC. The communications loops KS1, KS2 are in each case a 4-20 mA current loop, by means of which the respective measured process values of the field devices FG1, FG2 are transmitted to the superordinate unit SPC.

[0053] The superordinate unit SPC itself is connected to the control station LS of the installation via a network N, e.g., Ethernet or Profibus DP.

[0054] In order to read out diagnosis data from the field devices FG1, FG2, a respective communications module KM1, KM2 is plugged onto the cables of the respective communications loop KS1, KS2. The communications modules KS1, KS2 are preferably plugged onto the cables of the communications loops KS1, KS2 in the control cabinet, especially, at the point at which the cables of the communications loops KS1, KS2 are brought together to the superordinate unit SPC.

[0055] The communications modules KM1, KM2 are attached to the cables of the communications loops KS1, KS2 by means of insulation displacement terminals such that the communications modules KM1, KM2 are connected in parallel with the respectively corresponding field device FG1, FG2, which has the advantage that the communications loops KS1, KS2 do not have to be disconnected.

[0056] The communications modules KM1, KM2 comprise a transducer unit WE consisting of a rectifier circuit for generating electric power. For this purpose, the superordinate unit SPC is designed to generate these communication pulses. The communication pulses are an alternating current or an alternating voltage which is modulated onto the direct current of the communications loops KS1, KS2. This alternating current component is tapped by the transducer unit WE of the communications modules KM1, KM2. The rectifier circuit in the transducer unit WE rectifies the modulated alternating current component, transmits it to an energy storage unit EE connected downstream of the transducer unit WE, and stores it in the energy storage unit EE.

[0057] In this case, it can be provided that the communication pulse be a HART command. The superordinate unit SPC is then designed in such a way that it sends out the HART command at regular time intervals. The HART command itself is of no importance to the field device FG1, FG2 and contains, for example, an invalid command for the field device FG1, FG2 or a different receiving address than the network address of the field device FG1, FG2.

[0058] The amount of electric power stored in the energy storage unit EE is detected. As soon as a predetermined limit value, which is adjustable by the user, is reached in one of the communications modules, a polling unit AE located in the communications module KM1, KM2 sends a communication command to the corresponding field device FG1, FG2 for polling current diagnosis data of the field device FG1, FG2.

[0059] The communication command sent by the communications module KM1, KM2 to the field device FG1, FG2 is based upon HART. For this purpose, the communication command is modulated onto the present current value of the 4-20 mA current loop. In contrast to the superordinate unit SPC, the field device must be HART-enabled in order to understand the communication command.

[0060] The field device FG1, FG2 itself sends the desired diagnosis data back to the communications module KM1, KM2 by means of a HART communication pulse. Before commissioning, the communications module KM1, KM2 must, however, be configured in such a way that it knows the network address of the field device for polling the diagnosis data.

[0061] After the communications module KM1, KM2 has received the diagnosis data of the field device FG1, FG2, it augments them with additional information, such as a time stamp and the identification of the field device FG1, FG2. Subsequently, the diagnosis data are transmitted wirelessly by means of a transmission unit SE to a reception unit GW using electric power from the energy storage unit EE, whereupon the reception unit GW stores the diagnosis information.

[0062] Alternatively to reaching a limit value, the polling or transmission of the polled diagnosis data is triggered by a command, e.g., by a keypress on the housing of the respective communications module KM1, KM2.

[0063] The stored diagnosis information can then be read out of the reception unit GW by a PC, a mobile operating unit, or a mobile end device by means of a wired or a wireless communications link. Alternatively, the reception unit GW is connected to the control station LS of the installation and provides the stored diagnosis information to the control station.

[0064] FIG. 2 shows a second variant of an embodiment of the system according to the invention for transmitting diagnosis data from a plurality of field devices FG1, FG2 in an installation for process automation. In contrast to FIG. 1, the two communications loops KS1, KS2 are formed by fieldbuses, e.g., HART, Profibus PA, Foundation Fieldbus, Modbus, etc., via which the field devices FG1, FG2 communicate with the superordinate unit SPC.

[0065] Since the data are exchanged between the field devices and the superordinate unit via communication pulses, i.e., currents with an alternating current/alternating voltage component, the current conversion mechanism described in FIG. 1 cannot be used, since communication would be impaired otherwise. As an alternative, the communications modules KM1, KM2 each have a transducer element WE which converts light into electric power which is stored in the energy storage unit EE of the communications modules KM1, KM2.

[0066] If the communications modules KM1, KM2 are attached outside the control cabinet to the cables of the communications loops KS1, KS2, sunlight or illumination light of the installation can be received by the transducer unit WE in order to generate electric power.

[0067] If the communications modules KM1, KM2 are located in the control cabinet, and thus in the dark, the reception unit GW has a light source L. This light emitted by the light source L is received by the transducer unit WE of the communications modules KM1, KM2 and converted into electric power.

[0068] Alternatively, the reception unit GW comprises a radio module which emits an electromagnetic field or a magnetic field. The transducer unit WE has an induction coil or an antenna and can thus receive the electromagnetic or magnetic field and convert it into electric power.

[0069] None of the components FG1, FG2, SPC, LS of the installation shown in FIG. 2 has an internet-capable interface. In order to use diagnosis data of the field devices FG1, FG2 in the sense of IoT applications, expensive retrofitting of the components FG1, FG2, SPC, LS of the installation would be necessary. The reception unit GW therefore, advantageously, has an Internet interface via which the diagnosis data are sent to a web-based database DB. This can be done in both a wired and a wireless manner, e.g., via GSM. It may also be provided that another type of data, in particular process values, identification information, etc., be read out by means of the communications modules KM1, KM2 and sent to the web-based database DB via the reception unit. In this way, the installation can be easily and cost-effectively modernized for modern IoT applications.

[0070] It goes without saying that the method according to the invention and the system according to the invention can be used for any type and any number of field devices FG, and are not limited to the exemplary embodiments illustrated in FIG. 1 and FIG. 2.

LIST OF REFERENCE SYMBOLS

[0071] EE Energy storage unit

[0072] FG1, FG2 Field device

[0073] GW Reception unit

[0074] KM1, KM2 Communications module

[0075] KS1, KS2 Communications loop

[0076] L Light source

[0077] LS Control station of the installation

[0078] N Network

[0079] SPC Superordinate communications unit

[0080] SE Transmission unit

[0081] WE Transducer unit