HART acquisition or diagnosis circuit and method

Abstract

The embodiment of the invention provides an HART (Highway Addressable Remote Transducer) acquisition or diagnosis circuit and method, and the method comprises the steps: detecting equipment data when field equipment normally works through a 4-20mA power supply of a wireless HART information acquisition or diagnosis device, transmitting the equipment data to the wireless HART information acquisition or diagnosis device, and transmitting a 4-20mA analog signal to an analog input card; after the wireless HART information acquisition or diagnosis device receives equipment data in a communication manner, diagnosis data are generated based on the equipment data, and the diagnosis data are uploaded to an upper computer through an HART protocol; the analog quantity input card converts a 4-20 mA analog signal into a data signal and uploads the data signal to an upper computer through an HART (Highway Addressable Remote Transducer) protocol. Therefore, the problem that an original control system has no HART information acquisition function or no HART diagnosis information is solved under the condition that the overall topology of the site is not changed, a battery or an external power supply is not needed for power supply, the system can be placed on the engineering site for a long time, and real-time data or diagnosis data of various HART instruments can be checked in time through upper computer software.

Description

Technical Field

[0001] The present invention relates to the field of communication technology, and in particular to a HART acquisition or diagnosis circuit and method. Background Art

[0002] HART (Highway Addressable Remote Transducer) is an open communication protocol for addressable remote sensor high-speed channels. It was launched in 1985 as a communication protocol for field intelligent instruments and control room equipment. HART devices provide communication with relatively low bandwidth and moderate response time. After more than 30 years of development, HART technology has become very mature at home and abroad and has become the industrial standard for global intelligent instruments. The HART protocol can be used to conveniently and quickly manage field intelligent equipment instruments.

[0003] However, some factories’ DCS system cards do not support HART communication due to historical reasons, and are not in a position to make corrections. Alternatively, some customers pursue reliable control loops and hope to obtain or diagnose data on HART communication to prevent accidental shutdowns due to abnormal input and output signals, which can cause economic losses or casualties. Summary of the invention

[0004] In order to solve the technical problems mentioned above, such as the DCS system cards of some factories do not support HART communication and are not in a condition for rectification, or the abnormal signal leads to wrong parking, thus causing economic losses or casualties, a HART acquisition or diagnosis circuit and method are proposed, and the technical solution is as follows: In a first aspect, an embodiment of the present application provides a HART acquisition or diagnostic circuit, the circuit comprising a wireless HART information acquisition or diagnostic device, an analog input card, a field device, and a host computer, wherein: The wireless HART information acquisition or diagnosis device is connected to the analog input card, the field device, and the host computer respectively to provide the field device with 4-20mA power supply, collect the device data of the field device, and upload the device data to the host computer; The analog input card is connected to the field equipment to convert the 4-20mA analog signal of the field equipment into a digital signal, and upload the digital signal to the host computer; The host computer receives and displays the device data uploaded by the wireless HART information acquisition or diagnostic device and the digital signal uploaded by the analog input card.

[0005] In an optional solution of the first aspect, the wireless HART information acquisition or diagnosis device includes a 4-20mA loop power circuit, a HART modulation circuit, an MCU, a coupling capacitor and a wireless module unit, wherein: The first end of the 4-20mA loop power circuit is connected to the analog input card, the second end is connected to the field device, and the third end is connected to the HART modulation circuit and MCU, so as to reduce the current through a fixed voltage drop to power the field device, the modulation circuit, and the MCU; The first end of the HART modulation circuit is connected to the MCU, and the second end is connected to the analog input card through coupling capacitor coupling; The MCU is connected to the wireless module to process configuration information, serial port communication, and HART data modulation and demodulation.

[0006] In yet another optional solution of the first aspect, the 4-20 mA loop power supply circuit includes a constant voltage source circuit and a current limiting slow-start circuit.

[0007] In another optional solution of the first aspect, the constant voltage source circuit includes a first resistor, a second resistor and a voltage stabilizer, including: The first end of the first resistor is connected to the analog input card, and the second end is respectively connected to the first end of the second resistor and the cathode of the voltage regulator; The second end of the second resistor is connected to the field device; The anode of the voltage regulator is connected to the analog quantity input card, and the reference end is connected to the first end of the second resistor.

[0008] In another optional solution of the first aspect, the current limiting slow-start circuit includes a first capacitor, a second capacitor, a third capacitor, a third resistor, a fourth resistor, and a triode, including: The first end of the first capacitor is respectively connected to the first resistor, the voltage stabilizer, and the first resistor, and the second end is respectively connected to the second resistor, the voltage stabilizer, and the second end of the third capacitor; The first end of the second capacitor is respectively connected to the first end of the fourth resistor and the transistor, and the second end is respectively connected to the second end of the fourth resistor and the first end of the third capacitor; The first end of the third capacitor is respectively connected to the transistor, the second end of the second capacitor and the second end of the fourth resistor, and the second end is respectively connected to the second resistor, the voltage stabilizer and the second end of the first capacitor; The first end of the third resistor is respectively connected to the first resistor, the voltage stabilizer, and the first section of the first capacitor, and the second end is connected to the triode.

[0009] In a second aspect, an embodiment of the present application provides a HART acquisition or diagnosis method, which is applied to a HART acquisition or diagnosis circuit provided by the first aspect of the embodiment of the present application or any one of the implementations of the first aspect, and the method includes: When the field device works normally through the 4-20mA power supply of the wireless HART information acquisition or diagnostic device, the device data is detected and transmitted to the wireless HART information acquisition or diagnostic device, and the 4-20mA analog signal is transmitted to the analog input card; When the wireless HART information acquisition or diagnostic device receives the device data through communication, it generates diagnostic data based on the device data and uploads the diagnostic data to the host computer through the HART protocol; The analog input card converts the 4-20mA analog signal into a digital signal and uploads it to the host computer via the HART protocol.

[0010] In an optional solution of the second aspect, comprising: The 4-20mA current limiting current flowing into the first end of the first resistor and flowing out of the second end of the second resistor is stabilized by the constant voltage source circuit, and the third capacitor is charged by the current limiting slow-start circuit.

[0011] In an optional solution of the second aspect, the constant voltage source circuit satisfies the following formula: Wherein, circle 1 is the voltage at the first end of the first resistor, circle 2 is the voltage at the second end of the second resistor, V REF is the voltage of the voltage regulator, R1 is the first resistor, and R2 is the second resistor; Wherein, circle 3 is the voltage at the first terminal of the third capacitor, V be (Q1) is the voltage difference between the base and the emitter in transistor Q1; The first resistor and the second resistor are adjusted so that the voltage difference between the voltage at the first end of the first resistor and the voltage at the first end of the third capacitor is 3.3V.

[0012] In an optional solution of the second aspect, the diagnostic data includes: Device measurements, device status, and diagnostic information.

[0013] In a third aspect, an embodiment of the present application provides a computer storage medium, which stores a computer program. The computer program includes program instructions. When the program instructions are executed by a processor, the valve state control method based on power supply voltage provided by the second aspect of the embodiment of the present application or any implementation method of the second aspect can be implemented.

[0014] In view of the above, in one or more embodiments of the present specification, when the field equipment works normally through the 4-20mA power supply of the wireless HART information acquisition or diagnostic device, the equipment data is detected, and the equipment data is transmitted to the wireless HART information acquisition or diagnostic device, and the 4-20mA analog signal is transmitted to the analog input card; when the wireless HART information acquisition or diagnostic device receives the equipment data through communication, it generates diagnostic data based on the equipment data, and uploads the diagnostic data to the host computer through the HART protocol; the analog input card converts the 4-20mA analog signal into a data signal, and uploads it to the host computer through the HART protocol. In this way, without changing the overall topology of the site, the problem of the original control system having no HART information acquisition function or no HART diagnostic information is solved, and no battery or external power supply is required. It can be placed on the project site for a long time, and the real-time data or diagnostic data of various HART instruments can be viewed from time to time through the host computer software. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0016] Figure 1 It is a structural schematic diagram of a HART acquisition or diagnosis circuit provided by an embodiment of this specification.

[0017] Figure 2 This is a topological block diagram of a wireless HART information collection or diagnosis device provided in one embodiment of this specification.

[0018] Figure 3 It is a structural schematic diagram of a 4-20mA loop power supply circuit provided in an embodiment of this specification.

[0019] Figure 4 It is an overall flow chart of a HART acquisition or diagnosis method provided by an embodiment of this specification.

[0020] Figure 5 It is a structural schematic diagram of a HART acquisition or diagnosis device provided by an embodiment of this specification. DETAILED DESCRIPTION

[0021] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application.

[0022] In the following introduction, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance. The following introduction provides multiple embodiments of the present application, and different embodiments can be replaced or combined, so the present application can also be considered to include all possible combinations of the same and / or different embodiments recorded. Therefore, if one embodiment includes features A, B, and C, and another embodiment includes features B and D, then the present application should also be considered to include embodiments containing one or more of all other possible combinations of A, B, C, and D, although the embodiment may not be clearly recorded in the following text.

[0023] The following description provides examples and does not limit the scope, applicability or examples set forth in the claims. Changes may be made to the functions and arrangements of the elements described without departing from the scope of the present application. Various processes or components may be appropriately omitted, substituted or added to each example. For example, the described method may be performed in an order different from the order described, and various steps may be added, omitted or combined. In addition, features described in some examples may be combined in other examples.

[0024] See also Figure 1 , Figure 1 A structural schematic diagram of a HART acquisition or diagnosis circuit provided in an embodiment of the present application is shown.

[0025] like Figure 1 As shown, the HART acquisition or diagnosis circuit may include a wireless HART information acquisition or diagnosis device, an analog input card, a field device, and a host computer, wherein: The wireless HART information acquisition or diagnosis device is connected to the analog input card, the field device, and the host computer respectively to provide the field device with 4-20mA power supply, collect the device data of the field device, and upload the device data to the host computer; The analog input card is connected to the field equipment to convert the 4-20mA analog signal of the field equipment into a digital signal, and upload the digital signal to the host computer; The host computer receives and displays the device data uploaded by the wireless HART information acquisition or diagnostic device and the digital signal uploaded by the analog input card.

[0026] In this embodiment, the wireless HART information acquisition or diagnostic device collects analog signals from field devices or other sensors of field devices, converts them into digital signals, and communicates with a host computer or other devices through the wireless HART protocol, transmits the collected data, monitors the status of circuits and devices, and provides diagnostic information. The field device obtains power through the 4-20mA loop of the wireless HART information acquisition or diagnostic device to ensure normal operation, and generates analog signals (such as pressure, temperature, etc.), which are transmitted to the wireless HART information acquisition or diagnostic device and the analog input card through the 4-20mA loop. The analog input card converts the analog signal transmitted by the field device into a digital signal, and provides a standard interface to facilitate connection with the host computer or other control system, and performs preliminary processing and calibration on the collected signal. For analog input cards that support the HART protocol, in addition to traditional analog signals, low-frequency digital signals superimposed on the 4-20mA current can also be parsed to read additional HART data. The host computer is mainly used to centrally manage and analyze the data uploaded by the wireless HART information acquisition device and the analog input card. The host computer software can perform functions such as visual display, alarm management, historical record storage, and trend analysis on these data to help staff make operational adjustments and technical improvements.

[0027] It is understandable that the wireless HART information collection or diagnostic device is compatible with existing DCS systems and field equipment. Functional upgrades can be achieved through simple connections, and the use of 4-20mA loop power supply avoids the need for additional wiring and reduces installation complexity. Through wireless transmission and real-time monitoring, faults can be discovered and handled in a timely manner, improving the overall reliability and production efficiency of the system.

[0028] As an option of the embodiment of the present application, the wireless HART information acquisition or diagnosis device includes a 4-20mA loop power circuit, a HART modulation circuit, an MCU, a coupling capacitor and a wireless module unit, wherein: The first end of the 4-20mA loop power circuit is connected to the analog input card, the second end is connected to the field device, and the third end is connected to the HART modulation circuit and MCU, so as to reduce the current through a fixed voltage drop to power the field device, the modulation circuit, and the MCU; The first end of the HART modulation circuit is connected to the MCU, and the second end is connected to the analog input card through coupling capacitor coupling; The MCU is connected to the wireless module to process configuration information, serial port communication, and HART data modulation and demodulation.

[0029] In this embodiment, the 4-20mA loop power circuit includes three terminals, the first end is connected to the outside of the internal topology of the wireless HART information acquisition or diagnostic device, and is connected to the analog input card, the second end is also connected to the outside of the internal topology of the wireless HART information acquisition or diagnostic device, and is connected to the field device, and the third end is connected to the HART modulation circuit and MCU, so as to reduce the current through a fixed voltage drop to power the field device, and to power the modulation circuit and MCU. The HART modulation circuit includes a modulation and demodulation circuit, including various device schemes (SPWM filtering modulation, ADC acquisition HART soft cat algorithm), which will not be described in detail. The coupling method is to directly couple the analog input card through capacitor C1. The MCU mainly includes configuration information, serial port (wireless data reception / transmission), HART data modulation and demodulation (SPWM, ADC acquisition, soft cat algorithm), HART data processing (upward and downward transmission), etc. In the circuit of this embodiment, the MCU can be, but is not limited to, an MCU that supports low power consumption mode such as MP430 to save power consumption. The wireless module unit can select a wireless solution with a low power consumption mode such as Lora communication to save the consumption of the current loop, and the current consumption is low when sending data in the instantaneous state.

[0030] As an option in an embodiment of the present application, the 4-20mA loop power supply circuit includes a constant voltage source circuit and a current limiting slow-start circuit.

[0031] As an option of the embodiment of the present application, the constant voltage source circuit includes a first resistor, a second resistor and a voltage stabilizer, including: The first end of the first resistor is connected to the analog input card, and the second end is respectively connected to the first end of the second resistor and the cathode of the voltage regulator; The second end of the second resistor is connected to the field device; The anode of the voltage regulator is connected to the analog quantity input card, and the reference end is connected to the first end of the second resistor.

[0032] As an option of the embodiment of the present application, the current limiting slow-start circuit includes a first capacitor, a second capacitor, a third capacitor, a third resistor, a fourth resistor, and a transistor, including: The first end of the first capacitor is respectively connected to the first resistor, the voltage stabilizer, and the first resistor, and the second end is respectively connected to the second resistor, the voltage stabilizer, and the second end of the third capacitor; The first end of the second capacitor is respectively connected to the first end of the fourth resistor and the transistor, and the second end is respectively connected to the second end of the fourth resistor and the first end of the third capacitor; The first end of the third capacitor is respectively connected to the transistor, the second end of the second capacitor and the second end of the fourth resistor, and the second end is respectively connected to the second resistor, the voltage stabilizer and the second end of the first capacitor; The first end of the third resistor is respectively connected to the first resistor, the voltage stabilizer, and the first section of the first capacitor, and the second end is connected to the triode.

[0033] In this embodiment, the structural diagram of the 4-20mA loop power supply circuit can be as follows: Figure 3 As shown, Figure 3 It includes two parts: constant voltage source circuit and current limiting slow start circuit. In the constant voltage source circuit, after the 4-20mA current flows into the 1st foot, it is divided by the resistor 4-20mA and then stabilized by TL431 (U1). In the current limiting slow start circuit, in order to prevent the charging current from being too large and ensure the normal operation of the voltage stabilization circuit, it includes a 10uF first capacitor for energy storage and buffering, and at the same time provides a smaller AC impedance in the 4-20mA loop; a 100nF second capacitor for filtering; a 5mF third capacitor for energy storage to prevent instantaneous large current from causing voltage drop; a 50Ω third resistor for current limiting; a 1KΩ fourth resistor for biasing; and a transistor for current control. Through the constant voltage source circuit and the current limiting slow start circuit, the output voltage is ensured to be stable, providing a stable power supply for field equipment, MCU, wireless module and other circuits. In addition, the values ​​of the above-mentioned various components, such as the 10uF of the first capacitor, are all optional and can be 10uF but are not limited to 10uF. Corresponding adjustments can be made according to requirements during actual operation.

[0034] In another embodiment, see Figure 4 , Figure 4 An overall flow chart of a HART acquisition or diagnosis method provided in an embodiment of the present application is shown.

[0035] like Figure 4 As shown, the HART acquisition or diagnosis method can be applied to the HART acquisition or diagnosis circuit mentioned in one or more of the above embodiments, and the method may at least include the following steps: Step 402, when the field device works normally through the 4-20mA power supply of the wireless HART information acquisition or diagnostic device, the device data is detected and transmitted to the wireless HART information acquisition or diagnostic device, and the 4-20mA analog signal is transmitted to the analog input card.

[0036] Specifically, the field equipment obtains power through the 4-20mA loop in the wireless HART information acquisition or diagnostic device. When the field equipment is working normally, it will generate analog signals (such as pressure, temperature, etc.). The wireless HART information acquisition or diagnostic device is responsible for collecting the equipment data of the field equipment, detecting the equipment data, and transmitting the data to the host computer through the wireless HART protocol. In addition, the 4-20mA analog signal of the field equipment can also be transmitted to the analog input card, or indirectly transmitted to the analog input card through the wireless HART information acquisition or diagnostic device. For the wireless HART information acquisition or diagnostic device, it is connected between the DCS analog input card and the field equipment. Among them, pin 1 is connected to the A terminal of the analog input card to receive the digital signal of the analog input card, pin 2 is connected to the positive end of the field 4-20mA device to power the field equipment, and pin 3 is connected to the B terminal of the analog input card and the negative end of the field 4-20mA device.

[0037] Step 404, when the wireless HART information acquisition or diagnosis device receives the device data through communication, it generates diagnostic data based on the device data and uploads the diagnostic data to the host computer through the HART protocol.

[0038] Specifically, after the wireless HART information acquisition or diagnostic device receives the device data through communication, it generates diagnostic data based on the device data, including but not limited to determining the measurement value of the device, determining the current status of the device, and determining the diagnostic information of the device based on the measurement value and the current status, and uploads the diagnostic data to the host computer through the HART protocol for the host computer to transmit or display the diagnostic data.

[0039] Step 406: The analog input card converts the 4-20mA analog signal into a digital signal and uploads it to the host computer via the HART protocol.

[0040] Specifically, the analog input card converts the 4-20mA analog signal into a data signal and uploads it to the host computer through the HART protocol. When transmitting the signal, the analog input card provides a standard interface to facilitate connection with the host computer or other control systems.

[0041] In this embodiment, the power supply method is to select a 4-20mA loop to take power. The equipment is easy to install, does not require engineers to go to the site for operation, and can be tested for a long time. The operation is simple (host computer reading), the convenience is high, and problems can be eliminated in a timely manner.

[0042] As an optional embodiment of the present application, a constant voltage source circuit is used to stabilize the 4-20mA current flowing into the first end of the first resistor and out of the second end of the second resistor, and the third capacitor is charged through a current limiting slow-start circuit.

[0043] As another option of the embodiment of the present application, the constant voltage source circuit satisfies the following formula: Wherein, circle 1 is the voltage at the first end of the first resistor, circle 2 is the voltage at the second end of the second resistor, V REF is the voltage of the voltage regulator, R1 is the first resistor, and R2 is the second resistor; Wherein, circle 3 is the voltage at the first terminal of the third capacitor, V be (Q1) is the voltage difference between the base and the emitter in transistor Q1; The first resistor and the second resistor are adjusted so that the voltage difference between the voltage at the first end of the first resistor and the voltage at the first end of the third capacitor is 3.3V.

[0044] In this example, the 4-20mA current enters from pin 1 of the 4-20mA loop power circuit and flows out from pin 2, and is stabilized by the constant voltage source circuit. The large capacitor C3 is charged after passing through the current limiting slow start circuit. When the instantaneous current of the wireless module is large, the current limiting slow start circuit prevents the charging current from being too large and causing the voltage stabilization circuit to not work properly. The instantaneous charging current is small, and the C3 capacitor is charged with a small current for a long time, and is in a stable working state. The constant voltage source circuit satisfies the following formula: Wherein, circle 1 is the voltage at the first end of the first resistor, circle 2 is the voltage at the second end of the second resistor, V REF is the voltage of the voltage regulator, R1 is the first resistor, and R2 is the second resistor; Wherein, circle 3 is the voltage at the first terminal of the third capacitor, V be (Q1) is the voltage difference between the base and the emitter in transistor Q1; At this time, you need to select appropriate R1 and R2 to make V31 equal to 3.3V for use in MCU, wireless and other circuits.

[0045] In addition, C1 can store energy for the subsequent buffer circuit to prevent it from losing power when the subsequent charging circuit is working. It can also be connected in series in a 4-20mA loop to reduce its AC impedance and not affect the normal communication of DCS analog cards and instruments. This embodiment selects a 10uF capacitor, and the AC impedance is about 10Ω at the Hart operating frequency of 1.2K and 2.2K, which has little impact. C3 selects a larger capacitor of the mF level. When the wireless module sends data, it generates a large instantaneous current of tens of mA, which prevents the V circle 3 circle 1 from being pulled down to a smaller voltage, thereby preventing the MCU, wireless module, etc. from failing to work.

[0046] See also Figure 5 , Figure 5 A schematic structural diagram of a valve state control device based on power supply voltage provided in an embodiment of the present application is shown.

[0047] like Figure 5 As shown, the valve state control device 500 based on power supply voltage may include at least one processor 501 , at least one network interface 504 , a user interface 503 , a memory 505 and at least one communication bus 502 .

[0048] The communication bus 502 may be used to realize the connection and communication among the above-mentioned components.

[0049] The user interface 503 may include buttons, and the optional user interface may also include a standard wired interface or a wireless interface.

[0050] The network interface 504 may include, but is not limited to, a Bluetooth module, an NFC module, a Wi-Fi module, etc.

[0051] Among them, the processor 501 may include one or more processing cores. The processor 501 uses various interfaces and lines to connect various parts in the HART acquisition or diagnostic device 500, and executes various functions and processes data of the routing HART acquisition or diagnostic device 500 by running or executing instructions, programs, code sets or instruction sets stored in the memory 505, and calling data stored in the memory 505. Optionally, the processor 501 can be implemented in at least one hardware form of DSP, FPGA, and PLA. The processor 501 can integrate one or a combination of CPU, GPU, modem, etc. Among them, the CPU mainly processes the operating system, user interface, and application programs; the GPU is responsible for rendering and drawing the content to be displayed on the display screen; the modem is used to process wireless communications. It can be understood that the above-mentioned modem may not be integrated into the processor 501, and it can be implemented by a single chip.

[0052] The memory 505 may include a RAM or a ROM. Optionally, the memory 505 includes a non-transitory computer-readable medium. The memory 505 may be used to store instructions, programs, codes, code sets or instruction sets. The memory 505 may include a program storage area and a data storage area, wherein the program storage area may store instructions for implementing an operating system, instructions for at least one function (such as a touch function, a sound playback function, an image playback function, etc.), instructions for implementing the above-mentioned various method embodiments, etc.; the data storage area may store data involved in the above-mentioned various method embodiments, etc. The memory 505 may optionally be at least one storage device located away from the aforementioned processor 501. As Figure 5 As shown, the memory 505 as a computer storage medium may include an operating system, a network communication module, a user interface module, and a HART acquisition or diagnosis application.

[0053] Specifically, the processor 501 may be used to call a HART acquisition or diagnosis application stored in the memory 505, and specifically perform the following operations: When the field device works normally through the 4-20mA power supply of the wireless HART information acquisition or diagnostic device, the device data is detected and transmitted to the wireless HART information acquisition or diagnostic device, and the 4-20mA analog signal is transmitted to the analog input card; When the wireless HART information acquisition or diagnostic device receives the device data through communication, it generates diagnostic data based on the device data and uploads the diagnostic data to the host computer through the HART protocol; The analog input card converts the 4-20mA analog signal into a digital signal and uploads it to the host computer via the HART protocol.

[0054] In some possible embodiments, the following are included: The 4-20mA current limiting current flowing into the first end of the first resistor and flowing out of the second end of the second resistor is stabilized by the constant voltage source circuit, and the third capacitor is charged by the current limiting slow-start circuit.

[0055] The present application also provides a computer-readable storage medium on which a computer program is stored, and when the program is executed by a processor, the steps of the above method are implemented. The computer-readable storage medium may include, but is not limited to, any type of disk, including a floppy disk, an optical disk, a DVD, a CD-ROM, a micro drive, and a magneto-optical disk, a ROM, a RAM, an EPROM, an EEPROM, a DRAM, a VRAM, a flash memory device, a magnetic card or an optical card, a nanosystem (including a molecular memory IC), or any type of medium or device suitable for storing instructions and / or data.

[0056] It should be noted that, for the aforementioned method embodiments, for the sake of simplicity, they are all expressed as a series of action combinations, but those skilled in the art should be aware that the present application is not limited by the described order of actions, because according to the present application, certain steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also be aware that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily required by the present application.

[0057] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0058] In the several embodiments provided in the present application, it should be understood that the disclosed devices can be implemented in other ways. For example, the device embodiments described above are only schematic, such as the division of units, which is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some service interfaces, and the indirect coupling or communication connection of devices or units can be electrical or other forms.

[0059] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0060] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0061] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable memory. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a memory, including a number of instructions to enable a computer device (which can be a personal computer, server or network device, etc.) to execute all or part of the steps of the various embodiments of the present application. The aforementioned memory includes: U disk, read-only memory (ROM), random access memory (RAM), mobile hard disk, disk or optical disk and other media that can store program codes.

Claims

1. A HART acquisition or diagnostic circuit, characterized in that: The circuit includes a wireless HART information acquisition or diagnosis device, an analog input card, a field device and a host computer, wherein: The wireless HART information acquisition or diagnosis device is connected to the analog input card, the field device, and the host computer respectively to provide the field device with a 4-20mA power supply, collect the device data of the field device, and upload the device data to the host computer; The analog input card is connected to the field device to convert the 4-20mA analog signal of the field device into a digital signal, and upload the digital signal to the host computer; The host computer receives and displays the device data uploaded by the wireless HART information acquisition or diagnosis device and the digital signal uploaded by the analog input card.

2. The circuit according to claim 1, characterized in that The wireless HART information collection or diagnosis device includes a 4-20mA loop power circuit, a HART modulation circuit, an MCU, a coupling capacitor and a wireless module unit, wherein: The first end of the 4-20mA loop power circuit is connected to the analog input card, the second end is connected to the field device, and the third end is connected to the HART modulation circuit and the MCU, so as to reduce the current through a fixed voltage drop to power the field device, and to power the modulation circuit and the MCU; The first end of the HART modulation circuit is connected to the MCU, and the second end is coupled to the analog input card through the coupling capacitor; The MCU is connected to the wireless module to process configuration information, serial port communication, and HART data modulation and demodulation.

3. The method according to claim 2, characterized in that The 4-20mA loop power supply circuit includes a constant voltage source circuit and a current limiting slow-start circuit.

4. The method according to claim 3, characterized in that The constant voltage source circuit includes a first resistor, a second resistor and a voltage stabilizer, including: The first end of the first resistor is connected to the analog input card, and the second end is respectively connected to the first end of the second resistor and the cathode of the voltage regulator; The second end of the second resistor is connected to the field device; The anode of the voltage regulator is connected to the analog input card, and the reference end is connected to the first end of the second resistor.

5. The method according to claim 4, characterized in that The current limiting slow-start circuit comprises a first capacitor, a second capacitor, a third capacitor, a third resistor, a fourth resistor, and a triode, including: The first end of the first capacitor is respectively connected to the first resistor, the voltage stabilizer, and the first resistor, and the second end is respectively connected to the second resistor, the voltage stabilizer, and the second end of the third capacitor; The first end of the second capacitor is respectively connected to the first end of the fourth resistor and the transistor, and the second end is respectively connected to the second end of the fourth resistor and the first end of the third capacitor; The first end of the third capacitor is respectively connected to the transistor, the second end of the second capacitor and the second end of the fourth resistor, and the second end is respectively connected to the second resistor, the voltage stabilizer and the second end of the first capacitor; The first end of the third resistor is connected to the first resistor, the voltage stabilizer, and the first section of the first capacitor respectively, and the second end is connected to the transistor.

6. A HART acquisition or diagnosis method, characterized in that: The method is applied to the circuit according to any one of claims 1 to 5, and the method comprises: When the field device works normally through the 4-20mA power supply of the wireless HART information acquisition or diagnostic device, the device data is detected, and the device data is transmitted to the wireless HART information acquisition or diagnostic device, and the 4-20mA analog signal is transmitted to the analog input card; When the wireless HART information acquisition or diagnostic device receives the device data through communication, it generates diagnostic data based on the device data, and uploads the diagnostic data to the host computer through the HART protocol; The analog input card converts the 4-20mA analog signal into a data signal and uploads it to the host computer via the HART protocol.

7. The method according to claim 6, characterized in that The method further comprises: The constant voltage source circuit is used to stabilize the 4-20mA current limiting current flowing into the first end of the first resistor and flowing out of the second end of the second resistor, and the third capacitor is charged through the current limiting slow-start circuit.

8. The method according to claim 7, characterized in that The constant voltage source circuit satisfies the following formula: Wherein, circle 1 is the voltage at the first end of the first resistor, circle 2 is the voltage at the second end of the second resistor, V REF is the voltage of the voltage regulator, R1 is the first resistor, and R2 is the second resistor; Wherein, circle 3 is the voltage at the first terminal of the third capacitor, V be (Q1) is the voltage difference between the base and the emitter in transistor Q1; The first resistor and the second resistor are adjusted so that the voltage difference between the voltage at the first end of the first resistor and the voltage at the first end of the third capacitor is 3.3V.

9. The method according to claim 6, characterized in that The diagnostic data includes: Device measurements, device status, and diagnostic information.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: The computer-readable storage medium stores instructions, and when the instructions are executed on a computer or a processor, the computer or the processor executes the steps of the method according to any one of claims 6 to 9.

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