Magnetic flap liquid level meter and system based on APL technology

Abstract

The invention discloses a magnetic flap liquid level meter and system based on an APL technology, and relates to the field of industrial control. A magnetic flap liquid level device outputs a resistance value corresponding to the current liquid level of a measured container; the analog-to-digital signal acquisition module obtains a digital signal based on the resistance value; the microprocessor obtains a target liquid level corresponding to the resistance value contained in the digital signal based on a preset corresponding relation between the liquid level and the resistance value; the Ethernet communication module converts the target liquid level into a target signal based on a communication protocol belonging to an industrial Ethernet; and the two-wire system interface is used for sending the target signal. The magnetic flap liquid level meter can be directly connected with the Ethernet through a two-wire system interface by applying the APL technology, a target signal can be remotely transmitted through the Ethernet, and the problems that in the related technology, a magnetic flap liquid level device is complex to access the Ethernet, the transmission rate is low, industrial field wiring is difficult, and the input power is low are solved.

Description

Technical Field

[0001] The present application relates to the field of industrial control technology, and in particular to a magnetic flap level meter and system based on APL technology. Background Art

[0002] The magnetic flap liquid level device is mainly based on the principle of communicating vessels and magnetic coupling to achieve real-time measurement and display of the liquid level in the measured container.

[0003] In the related art, if it is necessary to remotely obtain the liquid level detected by the magnetic flap liquid level device, on-site personnel are required to arrive at the site to check and then upload the liquid level to the remote control device, which is cumbersome to operate. Summary of the invention

[0004] In view of the above problems, the present application provides a magnetic flap level meter and system based on APL technology to achieve the purpose of remotely obtaining the current liquid level detected in real time by the magnetic flap level device. The specific scheme is as follows:

[0005] The first aspect of the present application provides a magnetic flap level gauge based on APL technology, comprising:

[0006] The magnetic flap liquid level device is used to output the resistance value corresponding to the current liquid level of the measured container;

[0007] An analog-to-digital signal acquisition module, used for obtaining a digital signal based on the resistance value;

[0008] A microprocessor, configured to obtain a target liquid level corresponding to the resistance value included in the digital signal based on a preset correspondence between the liquid level and the resistance value;

[0009] An Ethernet communication module, used for converting the target liquid level into a target signal based on a communication protocol belonging to industrial Ethernet;

[0010] The two-wire interface is used to send the target signal.

[0011] In a possible implementation, the analog-to-digital signal acquisition module includes an analog-to-digital signal acquisition chip and a circuit module;

[0012] The IEXC1 terminal of the analog-to-digital signal acquisition chip is connected to the first end of the circuit module, and the analog-to-digital signal acquisition chip is used to input the excitation power flow into the circuit module through the IEXC1 terminal;

[0013] The AIN0 terminal of the analog-to-digital signal acquisition chip is connected to the second end of the circuit module;

[0014] The AIN3 terminal of the analog-to-digital signal acquisition chip is connected to the third end of the circuit module;

[0015] The AIN4 terminal of the analog-to-digital signal acquisition chip is connected to the fourth end of the circuit module.

[0016] In a possible implementation, the circuit module includes:

[0017] A first resistor, wherein a first end of the first resistor is a first end of the circuit module;

[0018] a second resistor, wherein a first end of the second resistor is a fourth end of the circuit module;

[0019] a first capacitor whose first end is connected to the first end of the second resistor, and a second end of the first capacitor is grounded;

[0020] A third resistor having a first end connected to the second end of the second resistor, and a second end of the third resistor connected to the second end of the first resistor and the first end of a fourth resistor respectively;

[0021] The fourth resistor, a second end of the fourth resistor is connected to the second end of the fifth resistor;

[0022] A sixth resistor having a second end connected to the first end of the fifth resistor, wherein the first end of the sixth resistor is the second end of the circuit module;

[0023] a second capacitor whose first end is connected to the first end of the sixth resistor, and whose second end is grounded;

[0024] a seventh resistor, wherein a first end of the seventh resistor is the third end of the circuit module;

[0025] A third capacitor having a first end connected to the first end of the seventh resistor, and a second end of the third capacitor being grounded;

[0026] An eighth resistor has a first end connected to the second end of the seventh resistor, and a second end of the eighth resistor is grounded.

[0027] In a possible implementation, if the magnetic flap liquid level device includes a reed switch, the second end of the fourth resistor is connected to one end of the magnetic flap liquid level device, and the second end of the eighth resistor is connected to the other end of the magnetic flap liquid level device.

[0028] In a possible implementation, the circuit module further includes a power interface.

[0029] In one possible implementation, if the magnetic flap liquid level device includes a Hall sensor, the second end of the fourth resistor is connected to one end of the magnetic flap liquid level device; the second end of the eighth resistor is grounded; the other end of the magnetic flap liquid level device is grounded, and the power interface is connected to a power module with an output voltage of 3.3 volts.

[0030] In a possible implementation, the corresponding relationship between the liquid level and the resistance value is:

[0031] L = (R-R0) / (R1-R0)×(URV-LRV)+LRV;

[0032] Wherein, R=resistance value of the fourth resistor×(V AIN0 -V AIN3 ) / (V AIN4 -V AIN0 ), V AIN0 is the voltage at the second end of the fourth resistor, V AIN4 is the voltage of the first end of the fourth resistor; V AIN3 is the voltage at the second end of the eighth resistor; R0 is the resistance value output by the magnetic flap liquid level device when the liquid level of the measured container is zero; R1 is the resistance value output by the magnetic flap liquid level device when the liquid level of the measured container is full; L is the current liquid level; LRV is the lowest liquid level value that the magnetic flap liquid level device can measure; URV is the highest liquid level value that the magnetic flap liquid level device can measure.

[0033] In a possible implementation, the Ethernet communication module is connected to the microprocessor via a 4-wire serial peripheral interface SPI.

[0034] In a possible implementation, the method further includes:

[0035] The power supply and reference circuit respectively supply power to the magnetic flap liquid level device, the analog-to-digital signal acquisition module, the microprocessor, the Ethernet communication module and the two-wire interface.

[0036] The second aspect of the present application provides a magnetic flap liquid level detection system based on APL technology, comprising:

[0037] A control device, used for sending a liquid level collection message, wherein the liquid level collection message includes a target IP address of a magnetic flap liquid level meter whose liquid level is to be obtained, and the structure of the magnetic flap liquid level meter is as described in claim 1;

[0038] An APL power switch connected to the control device for receiving the liquid level collection message and sending the liquid level collection message to the APL field switch via industrial Ethernet;

[0039] The APL field switch communicatively connected to the APL power switch is used to send the liquid level collection message to the magnetic flap level meter having the target IP address;

[0040] A magnetic flap level gauge having the target IP address and communicating with the APL field switch via industrial Ethernet, and configured to send the acquired target signal to the APL field switch;

[0041] The APL field switch is further used to feed back the target signal to the APL power switch;

[0042] The APL power switch is also used to feed back the target signal to the control device.

[0043] Through the above technical solution, the present application provides a magnetic flap level gauge based on APL technology, wherein the magnetic flap level device outputs the resistance value corresponding to the current liquid level of the measured container; the analog-to-digital signal acquisition module obtains a digital signal based on the resistance value; the microprocessor obtains the target liquid level corresponding to the resistance value contained in the digital signal based on the preset correspondence between the liquid level and the resistance value; the Ethernet communication module converts the target liquid level into a target signal based on a communication protocol belonging to the industrial Ethernet; a two-wire interface is used to send the target signal. The magnetic flap level gauge of the present application uses APL technology to be directly connected to the Ethernet through a two-wire interface, and the target signal can be remotely transmitted through the Ethernet, which solves the problems in the related art of complex Ethernet access for magnetic flap level devices, low transmission rate, difficult industrial field wiring, and low input power. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] The above and other features, advantages and aspects of the embodiments of the present disclosure will become more apparent with reference to the following detailed description in conjunction with the accompanying drawings. Throughout the accompanying drawings, the same or similar reference numerals represent the same or similar elements. It should be understood that the drawings are schematic and the originals and elements are not necessarily drawn to scale.

[0045] Figure 1 A schematic diagram of the structure of a magnetic flap liquid level detection system based on APL technology provided in this application;

[0046] Figure 2 A schematic diagram of an optional hardware structure of a control device 100 provided in this application;

[0047] Figure 3 A structural diagram of a magnetic flap level gauge based on APL technology provided in an embodiment of the present application;

[0048] Figure 4 A schematic diagram of a structure of an implementation method of an analog-to-digital signal acquisition module provided in an embodiment of the present application;

[0049] Figure 5 A result schematic diagram of an implementation method of the circuit module provided in an embodiment of the present application;

[0050] Figure 6 A schematic diagram of an application scenario of a magnetic flap level gauge based on APL technology provided in an embodiment of the present application. DETAILED DESCRIPTION

[0051] The following describes the embodiments of the present application in conjunction with the drawings in the embodiments of the present application. The terms used in the implementation method section of the present application are only used to explain the specific embodiments of the present application, and are not intended to limit the present application.

[0052] The embodiments of the present application are described below in conjunction with the accompanying drawings. Those skilled in the art will appreciate that, with the development of technology and the emergence of new scenarios, the technical solutions provided in the embodiments of the present application are also applicable to similar technical problems.

[0053] The terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and need not be used to describe a specific order or sequential order. It should be understood that the terms used in this way can be interchangeable under appropriate circumstances, which is only to describe the distinction mode adopted by the objects of the same attributes when describing in the embodiments of the present application. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, so that the process, method, system, product or equipment comprising a series of units need not be limited to those units, but may include other units that are not clearly listed or inherent to these processes, methods, products or equipment.

[0054] See also Figure 1 , Figure 1 The structure diagram of a magnetic flap liquid level detection system based on APL technology is shown. The system may include: a control device 11, one or more APL power switches 12, one or more APL field switches 13, and one or more magnetic flap liquid level meters 14.

[0055] The control device 11 is connected to the APL power switch 12 in communication. The APL power switch 12 is connected to the APL field switch 13 in communication. The APL field switch 13 is connected to the magnetic flap level meter 14 in communication.

[0056] In an optional implementation, the control device 11 is a remote device, and the liquid level collection message can be sent through the remote device. The liquid level collection message includes the target IP address of the magnetic flap level gauge whose liquid level is to be obtained. The APL power switch sends the liquid level collection message to the APL field switch. The APL field switch is used to send the liquid level collection message to the magnetic flap level gauge having the target IP address. The magnetic flap level gauge 14 with the target IP address is used to send the acquired target signal to the APL field switch. The APL field switch feeds back the target signal to the APL power switch; the APL power switch feeds back the target signal to the control device.

[0057] APL power switches are mainly used to connect industrial Ethernet and APL Trunk Ethernet to ensure communication and data transmission of different devices. APL power switches provide a variety of interface configurations, including support for 100M RJ45 electrical ports and SFP optical fiber interfaces to meet different network connection requirements, and are designed with 48VDC redundant power supply to enhance the stability and reliability of the system.

[0058] Exemplarily, the model of the APL power switch can be: AEP6204-2E2F-S model, AEP6208-2E2F-S model, AEP6212-2E2F-S model or AEP6216-2E2F-S model. Different models of APL power switches have different numbers of ports, and different models of APL power switches can adapt to network deployment requirements of different scales.

[0059] For example, the APL power switch provides detailed diagnostic information, including device type, working status, EBUS network communication status, redundancy status, address conflict detection, configuration status and startup status, etc., to help maintenance personnel quickly locate and solve problems. For example, if an EBUS network communication status failure occurs, maintenance personnel can follow the instructions to check the network cable, try to replace the network port or solve the network load problem, etc., to ensure the normal operation of the system.

[0060] For example, the APL power switch is also very important in the configuration and configuration of the magnetic flap liquid level detection system based on APL technology. It works together with the intelligent instrument management component included in the magnetic flap liquid level detection system based on APL technology to ensure that the communication driver of the instrument is correctly configured, thereby realizing effective management and control of field equipment (such as temperature transmitters, pressure transmitters, magnetic flap liquid level meters 14, etc.).

[0061] For example, the APL field switch model may be AEF6512-2T-S, which is designed for Figure 1The device of the system design shown. The APL field switch is used to connect the APL backbone network and the branch network. The APL field switch includes 2 APLRunk interfaces, and the 2 APLRunk interfaces are used for redundant connection with the APL backbone network. The APL field switch also includes multiple (for example, 12) APLSpur interfaces for connecting field devices such as temperature transmitters, pressure transmitters, magnetic flap level gauges 14, etc. The APL field switch not only provides data exchange function, but also can power the connected field devices through the APLRunk loop, supports overcurrent, undervoltage, overvoltage and short circuit protection, and ensures the stable operation of the field equipment.

[0062] The APL field switch is designed to meet industrial environment standards and has an IP66 protection level, making it suitable for direct use in harsh industrial sites and hazardous areas without the need for additional power distribution. During configuration, each APL Trunk node can add up to 4 APL field switches to expand network coverage and device connection capabilities.

[0063] Exemplarily, the APL field switch includes multiple channels, each channel is connected to a magnetic flap level meter 14, and the IP address of the magnetic flap level meter 14 connected to each channel is different.

[0064] Exemplarily, the model of the control device 11 may be FCU713.

[0065] In the related technology, the magnetic flap level device can output a standard electrical signal (such as 4~20mA). The traditional (4~20)mA current loop technology has the advantages of strong anti-interference ability, long transmission distance, and support for two-wire power supply, but it is a dedicated communication technology and needs to be connected to Ethernet through a gateway. The digital signal communication bandwidth superimposed on such analog signals is also very limited, and the data transmission rate is only 31 kilobits. In addition, due to the limitation of the (4~20)mA loop current, the input power is small, and the operation difficulty of the magnetic flap level device increases. Ordinary 10M / 100M Ethernet technology can achieve a one-to-one network from the top layer to the bottom layer, and interconnection, but it can only achieve data transmission within a range of 100 meters. If the magnetic flap level device is to be powered by active Ethernet (PoE) technology, at least 4 wires are required, and it is impossible to achieve parallel transmission of power and power supply, which does not conform to the common two-wire power supply habits in industrial sites.

[0066] APL is the advanced physical layer Ethernet, and its biggest features are long cable distance, intrinsic safety and application-level protocol support to achieve maximum productivity and output. The industrial control field has always pursued the goal of using Ethernet's one-to-one networking architecture to achieve connections from enterprise management systems, cloud platforms, field instruments to control systems. APL adopts the IEEE802.3cg protocol, has the characteristics of two-wire system, loop power supply, and can be deployed in explosion-hazardous areas. It realizes simultaneous communication and intrinsically safe power supply on two wires, and supports long-distance transmission and explosion-proof protection. At the same time, APL is a physical layer protocol. On this basis, HART-IP (Highway Addressable Remote Transducer over Internet Protocol), OPC UA (OPC Unified Architecture), PROFINET or other advanced protocols can be used for communication and transmission on this physical layer.

[0067] HART-IP is a communication protocol used in the field of industrial automation. It combines the HART (Highway Addressable Remote Transducer) protocol with the IP (Internet Protocol), allowing HART devices to be remotely monitored and controlled via Ethernet.

[0068] OPC UA (OPC Unified Architecture) is an open communication protocol used to implement data exchange and communication between devices in industrial automation systems. It provides a unified data model and communication mechanism, allowing devices from different manufacturers to communicate and integrate with each other.

[0069] PROFINET is an Ethernet communication protocol used in industrial automation. It supports real-time communication and high-speed data transmission, and provides flexible network topology and device configuration. PROFINET can be used to connect various industrial devices, such as sensors, actuators, PLCs, etc., to achieve real-time control and data exchange.

[0070] The magnetic flap level meter 14 in the embodiment of the present application utilizes APL technology, is capable of modulating and demodulating 10BASE-T1L signals, and sending and receiving through a two-wire interface, thereby realizing data interaction between the magnetic flap level meter 14 and industrial Ethernet.

[0071] 10BASE-T1L is an Ethernet physical layer standard for transmitting data over a single twisted pair. It supports a maximum transmission rate of 10 Mbps and uses baseband transmission technology. T1L means that the standard is suitable for links up to 1 km. This standard is often used in applications such as industrial automation and vehicle networks.

[0072] The magnetic flap level meter of the present invention can be directly connected to the Ethernet using the APL technology and is powered according to the data line power supply technology, thereby realizing the parallel transmission of data and power on a pair of twisted pair cables, solving the problems in the related art of complex Ethernet access for magnetic flap level devices, low transmission rate, difficult industrial field wiring, and low input power.

[0073] Figure 2 An optional hardware structure diagram of the control device 100 is shown.

[0074] refer to Figure 2 As shown, the control device 100 may include a radio frequency unit 110, a memory 120, an input unit 130, a display unit 140, a camera 150 (optional), an audio circuit 160 (optional), a speaker 161 (optional), a microphone 162 (optional), an earphone jack 163 (optional), a processor 170, an external interface 180, a power supply 190 and other components. Those skilled in the art will appreciate that Figure 2 This is merely an example of a control device and does not constitute a limitation on the control device. The control device may include more or fewer components than shown in the figure, or a combination of certain components, or different components.

[0075] The input unit 130 can be used to receive input digital or character information, and generate key signal input related to the user settings and function control of the control device. Specifically, the input unit 130 may include a touch screen 131 (optional) and / or other input devices 132. The touch screen 131 can collect the user's touch operations on or near it (such as the user's operation on or near the touch screen using any suitable object such as fingers, joints, stylus, etc.), and drive the corresponding connection device according to a pre-set program. The touch screen can detect the user's touch action on the touch screen, convert the touch action into a touch signal and send it to the processor 170, and can receive and execute the command sent by the processor 170; the touch signal at least includes the touch point coordinate information. The touch screen 131 can provide an input interface and an output interface between the control device 100 and the user. In addition, the touch screen can be implemented using multiple types such as resistive, capacitive, infrared and surface acoustic wave. In addition to the touch screen 131, the input unit 130 can also include other input devices. Specifically, other input devices 132 may include, but are not limited to, one or more of a physical keyboard, function keys (such as a volume control key, a switch key, etc.), a trackball, a mouse, a joystick, and the like.

[0076] Among them, the input device 132 can receive input data and the like.

[0077] The display unit 140 may be used to display information input by a user or information provided to a user, control various menus of the device 100, interactive interfaces, file display, and / or playback of any multimedia file.

[0078] The memory 120 can be used to store instructions and data. The memory 120 can mainly include an instruction storage area and a data storage area. The data storage area can store various data, such as multimedia files, texts, etc.; the instruction storage area can store software units such as operating systems, applications, instructions required for at least one function, or their subsets and extensions. It can also include a non-volatile random access memory; provide the processor 170 with hardware, software and data resources including management of computing and processing equipment, and support control software and applications. It is also used for the storage of multimedia files, and the storage of running programs and applications.

[0079] The processor 170 is the control center of the control device 100. It uses various interfaces and lines to connect various parts of the entire control device 100. By running or executing instructions stored in the memory 120 and calling data stored in the memory 120, it executes various functions of the control device 100 and processes data, thereby controlling the control device as a whole. Optionally, the processor 170 may include one or more processing units; preferably, the processor 170 may integrate an application processor and a modem processor, wherein the application processor mainly processes the operating system, user interface and application program, and the modem processor mainly processes wireless communication. It is understandable that the above-mentioned modem processor may not be integrated into the processor 170. In some embodiments, the processor, memory, can be implemented on a single chip, and in some embodiments, they can also be implemented separately on independent chips. The processor 170 can also be used to generate corresponding operation control signals, send them to the corresponding components of the computing and processing device, read and process data in the software, especially read and process data and programs in the memory 120, so that each functional module therein performs corresponding functions, thereby controlling the corresponding components to act according to the requirements of the instructions.

[0080] The radio frequency unit 110 (optional) can be used for receiving and sending information or receiving and sending signals during a call, for example, after receiving the downlink information of the base station, it is sent to the processor 170 for processing; in addition, the designed uplink data is sent to the base station. Generally, the RF circuit includes but is not limited to an antenna, at least one amplifier, a transceiver, a coupler, a low noise amplifier (Low Noise Amplifier, LNA), a duplexer, etc. In addition, the radio frequency unit 110 can also communicate with network devices and other devices through wireless communication. The wireless communication can use any communication standard or protocol, including but not limited to Global System of Mobile communication (Global System of Mobile communication, GSM), General Packet Radio Service (General Packet Radio Service, GPRS), Code Division Multiple Access (Code Division Multiple Access, CDMA), Wideband Code Division Multiple Access (Wideband Code Division Multiple Access, WCDMA), Long Term Evolution (Long Term Evolution, LTE), email, Short Messaging Service (SMS), etc.

[0081] In this embodiment of the present application, the RF unit 110 can send data to the server 200 and receive processing results sent by the server 200.

[0082] It should be understood that the radio frequency unit 110 is optional and can be replaced by other communication interfaces, such as a network port.

[0083] The control device 100 also includes a power supply 190 (such as a battery) for supplying power to each component. Preferably, the power supply can be logically connected to the processor 170 through a power management system, so that the power management system can manage functions such as charging, discharging, and power consumption.

[0084] The control device 100 further includes an external interface 180 , which may be a standard Micro USB interface or a multi-pin connector, and may be used to connect the control device 100 to communicate with other devices, or may be used to connect a charger to charge the control device 100 .

[0085] Although not shown, the control device 100 may also include a flashlight, a wireless fidelity (WiFi) module, a Bluetooth module, sensors with different functions, etc., which are not described in detail here. Some or all of the methods described below may be applied to Figure 2 In the control device 100 shown.

[0086] Reference Figure 3 , Figure 3 A structural diagram of a magnetic flap level gauge based on APL technology provided in an embodiment of the present application, such as Figure 3 As shown in the figure, the magnetic flap level meter based on APL technology is Figure 1 The magnetic flap level gauge 14 includes: a magnetic flap level device 31 , an analog-to-digital signal acquisition module 32 , a microprocessor 33 , an Ethernet communication module 34 and a two-wire interface 35 .

[0087] The magnetic flap liquid level device 31 is used to output the resistance value corresponding to the current liquid level of the measured container.

[0088] The analog-to-digital signal acquisition module 32 is used to obtain a digital signal based on the resistance value.

[0089] The microprocessor 33 is used to obtain the target liquid level corresponding to the resistance value included in the digital signal based on the preset corresponding relationship between the liquid level and the resistance value.

[0090] The Ethernet communication module 34 is used to convert the target liquid level into a target signal based on a communication protocol belonging to the industrial Ethernet.

[0091] The two-wire interface 35 is used to send the target signal.

[0092] Exemplarily, the magnetic flap level meter based on APL technology may also include a power supply and a reference circuit 36; wherein the power supply and the reference circuit 36 ​​respectively power the magnetic flap level device 31, the analog-to-digital signal acquisition module 32, the microprocessor 33, the Ethernet communication module 34 and the two-wire interface 35.

[0093] Exemplarily, the power supply and reference circuit 36 ​​includes a power chip. The power supply and reference circuit 36 ​​can convert the (9-15)V input voltage into a stable and reliable reference voltage through the power chip, and then supply power to the magnetic flap liquid level device 31, the analog-to-digital signal acquisition module 32, the microprocessor 33, the Ethernet communication module 34 and the two-wire interface 35.

[0094] Exemplarily, the Ethernet communication module 34 complies with the IEEE Ethernet standard, is suitable for industrial Ethernet intrinsically safe applications and long-distance 10 Mbps single-pair Ethernet, and is directly connected to the microprocessor 33 via a 4-wire SPI (Serial Peripheral Interface) to achieve mutual conversion between communication data and 10BASE-T1L signals.

[0095] Exemplarily, the magnetic flap liquid level device 31 has a variety of structures, and two structures are described below.

[0096] The first magnetic flap liquid level device 31 includes: a measuring main float tube, a magnetic flap indicator, a drain valve assembly, a process connection flange, a UR type resistance sensor, a UB type R / I conversion module, a magnetic float, and a reed switch. The functions of each module are as follows:

[0097] Measuring main float tube: The process connection flange or other connecting elements are connected to the measured container to form a communicating vessel structure, and the liquid level inside is at the same height as the liquid level in the measured container.

[0098] Magnetic flap indicator: tied to the outside of the float tube, used to indicate the liquid level on site.

[0099] Drain valve assembly: used to discharge liquid when cleaning or debugging the liquid level meter.

[0100] Process connection flange: used to connect the measuring main float tube to the container.

[0101] UR type resistance sensor: bundled on the outside of the main conduit of the magnetic flap liquid level device, and is in the same magnetic coupling system with the magnetic flap liquid level device.

[0102] UB type R / I conversion module: converts the changing resistance signal into a 4~20mA current signal output.

[0103] Magnetic float: Floats on the liquid surface of the float, contains permanent magnets inside, and moves up and down as the liquid level changes.

[0104] Reed switch: neatly arranged in the transmitter measuring tube, the magnetic float triggers the action of the reed switch at the corresponding position when it moves with the liquid level.

[0105] Through the cooperation of the reed switch and the resistance sensor, the magnetic flap liquid level device 31 can convert the liquid level change into an electrical signal, and then be used in conjunction with electric instruments, displays and other equipment to achieve the purposes of display, control, regulation and alarm.

[0106] The second magnetic flap liquid level device 31 includes: an indicator, a magnetic float, a buoy, a Hall sensor, a sensor, an input circuit, an output circuit, a connecting flange, and a drain valve; wherein the functions of each module are as follows:

[0107] Indicator: Used to indicate the liquid level in the measured container on site, usually installed together with the float.

[0108] Magnetic float: It is in direct contact with the liquid in the container being measured in the float, and rises and falls with the rise and fall of the liquid level in the container being measured.

[0109] Float: It is connected to the measured container through process connection to form a communicating vessel structure to achieve liquid level measurement.

[0110] Hall sensor: used to detect the state of the magnetic flap and convert it into an electrical signal. The Hall element can sense changes in the magnetic field. When the magnetic float moves, the Hall sensor can detect the change in the magnetic field and generate a corresponding electrical signal.

[0111] Sensor: Used in conjunction with the Hall element to detect the movement and position of the magnetic flap.

[0112] Input circuit: used to amplify the signal generated by the Hall sensor.

[0113] Output circuit: Converts the amplified signal into a standard electrical signal, such as a 4-20mA current output signal, for remote monitoring and control.

[0114] Connecting flange: used to connect the measuring main float tube to the container.

[0115] Drain valve: used to discharge liquid when cleaning or debugging the liquid level meter.

[0116] Through the cooperation of Hall sensors and remote transmitters, the magnetic flap level gauge can convert liquid level changes into electrical signals, and then be used in conjunction with electric instruments, displays and other equipment to achieve the purposes of display, control, regulation and alarm.

[0117] For example, the Ethernet communication module can convert the data into a 10BASE-T1L signal and send it out through a two-wire interface. The Ethernet communication module acquires and demodulates the 10BASE-T1L signal through the two-wire interface to obtain the liquid level collection message.

[0118] The present application provides a magnetic flap level gauge based on APL technology, wherein the magnetic flap level device outputs the resistance value corresponding to the current liquid level of the measured container; the analog-to-digital signal acquisition module obtains a digital signal based on the resistance value; the microprocessor obtains the target liquid level corresponding to the resistance value contained in the digital signal based on the preset correspondence between the liquid level and the resistance value; the Ethernet communication module converts the target liquid level into a target signal based on a communication protocol belonging to the industrial Ethernet; and a two-wire interface is used to send the target signal. The magnetic flap level gauge of the present application uses APL technology to be directly connected to the Ethernet through a two-wire interface, and the target signal can be remotely transmitted through the Ethernet, solving the problems in the related art of complex Ethernet access for magnetic flap level devices, low transmission rate, difficult industrial field wiring, and low input power.

[0119] The structure of the analog-to-digital signal acquisition module in the embodiment of the present application is described below.

[0120] like Figure 4 FIG. 4 is a schematic diagram of a structure of an implementation of an analog-to-digital signal acquisition module provided in an embodiment of the present application, wherein the analog-to-digital signal acquisition module includes an analog-to-digital signal acquisition chip 41 and a circuit module 42 .

[0121] The IEXC1 terminal of the analog-to-digital signal acquisition chip is connected to the first end of the circuit module, and the analog-to-digital signal acquisition chip is used to input the excitation power flow into the circuit module through the IEXC1 terminal.

[0122] The AIN0 terminal of the analog-to-digital signal acquisition chip is connected to the second end of the circuit module.

[0123] The AIN3 terminal of the analog-to-digital signal acquisition chip is connected to the third end of the circuit module.

[0124] The AIN4 terminal of the analog-to-digital signal acquisition chip is connected to the fourth end of the circuit module.

[0125] The fourth end of the circuit module is connected to the magnetic flap liquid level device.

[0126] The analog-to-digital signal acquisition chip inputs an excitation current source to the circuit module through the IEXC1 terminal. The AIN0 terminal, AIN3 terminal and AIN4 terminal of the analog-to-digital signal acquisition chip are three acquisition channels.

[0127] Exemplarily, the model of the analog-to-digital signal acquisition chip 41 may be ADS1148.

[0128] like Figure 5 , which is a schematic diagram of the result of an implementation method of the circuit module provided in an embodiment of the present application.

[0129] like Figure 5 As shown, the circuit module includes: a first resistor R6, a second resistor R8, a third resistor L1, a fourth resistor RJ1, a fifth resistor L2, a sixth resistor R9, a seventh resistor R10, an eighth resistor L3, a first capacitor C4, a second capacitor C5, and a third capacitor C8.

[0130] Exemplarily, the parameter of the first resistor R6 is 0603-1 / 8W-1k.

[0131] Exemplarily, the parameters of the second resistor R8, the sixth resistor R9 and the seventh resistor R10 are all 0603-1 / 8W-5.1k.

[0132] Exemplarily, the parameters of the third resistor L1 , the fifth resistor L2 , and the eighth resistor L3 are all FCM-0805-1A-2k.

[0133] Exemplarily, the parameters of the first capacitor C4, the second capacitor C5, and the third capacitor C8 are: X7R-0603-50V-0.1μF.

[0134] Exemplarily, the parameters of the fourth resistor RJ1 are: 1206-0.25w-249R.

[0135] Among them, the first end of the first resistor is the first end of the circuit module; the first end of the sixth resistor is the second end of the circuit module; the first end of the seventh resistor is the third end of the circuit module; and the first end of the second resistor is the fourth end of the circuit module.

[0136] The second end of the first resistor R6 is connected to the second end of the third resistor L1; the second end of the second resistor R8 is connected to the first end of the third resistor L1; the first end of the second resistor R8 is connected to the first end of the first capacitor C4; the second end of the first capacitor C4 is grounded. The second end of the third resistor L1 is connected to the first end of the fourth resistor RJ1; the second end of the fourth resistor RJ1 is connected to the second end of the fifth resistor L2; the first end of the fifth resistor L2 is connected to the second end of the sixth resistor R9; the first end of the sixth resistor R9 is connected to the first end of the second capacitor C5; the second end of the second capacitor C5 is grounded; the first end of the seventh resistor R10 is connected to the first end of the third capacitor C8; the second end of the third capacitor C8 is grounded; the second end of the seventh resistor R10 is connected to the first end of the eighth resistor L3; the second end of the eighth resistor L3 is grounded.

[0137] In an optional implementation, the circuit module further includes: a power interface. Exemplarily, the power interface is used to connect to a power module with an output voltage of 3.3 volts.

[0138] like Figure 5 As shown, in the embodiment of the present application, the second end of the fourth resistor RJ1 is called the tp1 end, the second end of the eighth resistor L3 is called the tp4 end, and the power interface is called the tp3 end.

[0139] In an optional implementation, if the magnetic flap liquid level device includes a reed switch, the second end of the fourth resistor is connected to one end of the magnetic flap liquid level device, and the second end of the eighth resistor is connected to the other end of the magnetic flap liquid level device.

[0140] In an optional implementation, if the magnetic flap liquid level device includes a Hall sensor, the second end of the fourth resistor is connected to one end of the magnetic flap liquid level device; the second end of the eighth resistor is grounded; the other end of the magnetic flap liquid level device is grounded, and the power interface is connected to a power module with an output voltage of 3.3 volts. The power module is used to power the Hall sensor.

[0141] It can be understood that, no matter whether the magnetic flap liquid level device includes a reed switch or a Hall sensor, the tp1 end and the tp4 end of the analog-to-digital signal acquisition module are equivalent to being connected to the two ends of the magnetic flap liquid level device respectively. Since the magnetic flap liquid level device will output a resistance signal representing the resistance value. Therefore, the magnetic flap liquid level device is equivalent to a resistor, which is referred to as the magnetic flap resistor R in the embodiment of the present application.

[0142] Combination Figure 5 It can be seen that the current passing through the fourth resistor RJ1 and the magnetic flip resistor R is the same, so the differential voltage signal (V AIN0 -V AIN3 , through the differential voltage signal between the AIN0 terminal and the AIN4 terminal) (V AIN4 -V AIN0 ) can be used to calculate the magnetic flip plate resistance R.

[0143] Since the current passing through the fourth resistor RJ1 and the magnetic flip resistor R is the same, the following formula can be obtained:

[0144] .

[0145] From the above formula, we can derive the formula: .

[0146] Among them, V AIN0 is the voltage at the second end of the fourth resistor, V AIN4 is the voltage of the first end of the fourth resistor; V AIN3is the voltage at the second end of the eighth resistor.

[0147] For example, if the parameters of the second resistor R8, the sixth resistor R9 and the seventh resistor R10 are the same; the parameters of the third resistor L1, the fifth resistor L2 and the eighth resistor L3 are the same; the parameters of the first capacitor C4, the second capacitor C5 and the third capacitor C8 are the same, then V AIN0 is the voltage of AIN0 terminal, V AIN3 is the voltage of AIN3 terminal, V AIN4 is the voltage of the AIN4 terminal.

[0148] Exemplarily, the “correspondence between liquid level and resistance value” stored in the microprocessor is as follows:

[0149] L = (R-R0) / (R1-R0)×(URV-LRV)+LRV;

[0150] Among them, R0 is the resistance value output by the magnetic flap liquid level device when the liquid level of the measured container is zero point; R1 is the resistance value output by the magnetic flap liquid level device when the liquid level of the measured container is full point; L is the current liquid level; LRV is the lowest liquid level value that the magnetic flap liquid level device can measure; URV is the highest liquid level value that the magnetic flap liquid level device can measure.

[0151] Exemplarily, the fourth resistor RJ1 is a precision resistor.

[0152] In an optional implementation, the magnetic flap level gauge based on the APL technology also includes: a display module: used to display data such as the current liquid level and alarm information in real time, and the human-computer interaction function is also realized through this module.

[0153] In an optional implementation, the magnetic flap level gauge based on the APL technology further includes: a storage module: used for storing and reading data such as the correspondence between the liquid level and the resistance value and alarm diagnosis.

[0154] Exemplarily, the microprocessor is connected to the storage module and the display module respectively.

[0155] The magnetic flap liquid level detection system based on APL technology provided in the embodiment of the present application has a simple topological structure, and any Ethernet-based protocol or application can be used. It supports the trunk and fork topologies widely used in field buses, and realizes end-to-end communication based on the Internet Protocol (IP) from the cloud to the sensor node. The maximum transmission distance of the backbone network is 1000 meters at a rate of 10Mbps, and the transmission distance of the branch is 200 meters. It meets the two-wire requirements and special explosion-proof and intrinsic safety requirements of magnetic flap level meters based on APL technology that have been used to date, and also provides flexibility for predictive maintenance.

[0156] The magnetic flap level meter based on APL technology provided in the embodiment of the present application is convenient to access Ethernet. The magnetic flap level meter based on APL technology can be easily integrated into the Ethernet environment without the need for additional gateways and interfaces, and can be transparently connected to any IT network. Ethernet can also simplify the parameter setting, initialization and programming of the device.

[0157] The magnetic flap liquid level detection system based on APL technology provided in the embodiment of the present application is low-cost. It can replace the more expensive optical cable with Ethernet cable, or use the existing twisted pair cable already laid on site, making the equipment operation and maintenance more efficient. Directly integrate Ethernet, replace or simplify certain fieldbus protocols, and eliminate the need for complex gateway solutions, saving the cost of converting different protocols between different devices.

[0158] The magnetic flap liquid level detection system based on APL technology provided in the embodiment of the present application takes advantage of the APL bus transmission. The radar level meter can upload a series of information such as alarm information and diagnostic data to the field bus control system and communicate efficiently with the system.

[0159] The 10BASE-T1L APL field switch can provide more input power than the (4~20)mA power supply in related technologies, improving the problem that the instrument cannot start when the (4~20)mA low current power supply is used.

[0160] In order for those skilled in the art to better understand the magnetic flap level gauge based on APL technology provided in the embodiment of the present application, a specific application scenario is given below for illustration.

[0161] like Figure 6 The figure shows a schematic diagram of an application scenario of a magnetic flap level gauge based on the APL technology provided in an embodiment of the present application.

[0162] Figure 6 Two types of magnetic flap level gauges based on APL technology are shown, such as Type A and Type B.

[0163] It should also be noted that the device embodiments described above are merely schematic, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed over multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. In addition, in the drawings of the device embodiments provided by the present application, the connection relationship between the modules indicates that there is a communication connection between them, which may be specifically implemented as one or more communication buses or signal lines.

[0164] Through the description of the above implementation mode, the technicians in the field can clearly understand that the present application can be implemented by means of software plus necessary general hardware, and of course, it can also be implemented by special hardware including special integrated circuits, special CPUs, special memories, special components, etc. In general, all functions completed by computer programs can be easily implemented by corresponding hardware, and the specific hardware structure used to implement the same function can also be various, such as analog circuits, digital circuits or special circuits. However, for the present application, software program implementation is a better implementation mode in more cases. Based on such an understanding, the technical solution of the present application is essentially or the part that contributes to the prior art can be embodied in the form of a software product, which is stored in a readable storage medium, such as a computer floppy disk, a U disk, a mobile hard disk, a ROM, a RAM, a magnetic disk or an optical disk, etc., including a number of instructions to enable a computer device (which can be a personal computer, a training device, or a network device, etc.) to execute the methods described in each embodiment of the present application.

[0165] In the above embodiments, all or part of the embodiments may be implemented by software, hardware, firmware or any combination thereof. When implemented by software, all or part of the embodiments may be implemented in the form of a computer program product.

[0166] The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the process or function described in the embodiment of the present application is generated in whole or in part. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. The computer instructions may be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions may be transmitted from a website site, a computer, a training device, or a data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) mode to another website site, computer, training device, or data center. The computer-readable storage medium may be any available medium that a computer can store or a data storage device such as a training device, a data center, etc. that includes one or more available media integrations. The available medium may be a magnetic medium, (e.g., a floppy disk, a hard disk, a tape), an optical medium (e.g., a DVD), or a semiconductor medium (e.g., a solid-state drive (SSD)), etc.

Claims

1. A magnetic flap level gauge based on APL technology, characterized in that: include: The magnetic flap liquid level device is used to output the resistance value corresponding to the current liquid level of the measured container; An analog-to-digital signal acquisition module, used for obtaining a digital signal based on the resistance value; A microprocessor, configured to obtain a target liquid level corresponding to the resistance value included in the digital signal based on a preset correspondence between the liquid level and the resistance value; An Ethernet communication module, used for converting the target liquid level into a target signal based on a communication protocol belonging to industrial Ethernet; The two-wire interface is used to send the target signal.

2. According to the magnetic flap level gauge based on APL technology in claim 1, it is characterized in that: The analog-to-digital signal acquisition module includes an analog-to-digital signal acquisition chip and a circuit module; The IEXC1 terminal of the analog-to-digital signal acquisition chip is connected to the first end of the circuit module, and the analog-to-digital signal acquisition chip is used to input the excitation power flow into the circuit module through the IEXC1 terminal; The AIN0 terminal of the analog-to-digital signal acquisition chip is connected to the second end of the circuit module; The AIN3 terminal of the analog-to-digital signal acquisition chip is connected to the third end of the circuit module; The AIN4 terminal of the analog-to-digital signal acquisition chip is connected to the fourth end of the circuit module.

3. According to the magnetic flap level gauge based on APL technology as claimed in claim 2, it is characterized in that: The circuit module comprises: A first resistor, wherein a first end of the first resistor is a first end of the circuit module; a second resistor, wherein a first end of the second resistor is a fourth end of the circuit module; a first capacitor whose first end is connected to the first end of the second resistor, and a second end of the first capacitor is grounded; A third resistor having a first end connected to the second end of the second resistor, and a second end of the third resistor connected to the second end of the first resistor and the first end of a fourth resistor respectively; The fourth resistor, a second end of the fourth resistor is connected to the second end of the fifth resistor; A sixth resistor having a second end connected to the first end of the fifth resistor, wherein the first end of the sixth resistor is the second end of the circuit module; a second capacitor whose first end is connected to the first end of the sixth resistor, and whose second end is grounded; a seventh resistor, wherein a first end of the seventh resistor is the third end of the circuit module; A third capacitor having a first end connected to the first end of the seventh resistor, and a second end of the third capacitor being grounded; An eighth resistor has a first end connected to the second end of the seventh resistor, and a second end of the eighth resistor is grounded.

4. According to the magnetic flap level gauge based on APL technology as claimed in claim 3, it is characterized in that: If the magnetic flap liquid level device includes a reed switch, the second end of the fourth resistor is connected to one end of the magnetic flap liquid level device, and the second end of the eighth resistor is connected to the other end of the magnetic flap liquid level device.

5. According to the magnetic flap level gauge based on APL technology as claimed in claim 3, it is characterized in that: The circuit module also includes a power supply interface.

6. According to the magnetic flap level gauge based on APL technology as claimed in claim 5, it is characterized in that: If the magnetic flap liquid level device includes a Hall sensor, the second end of the fourth resistor is connected to one end of the magnetic flap liquid level device; the second end of the eighth resistor is grounded; the other end of the magnetic flap liquid level device is grounded, and the power interface is connected to a power module with an output voltage of 3.3 volts.

7. The magnetic flap level gauge based on APL technology according to any one of claims 4 to 6, characterized in that: The corresponding relationship between the liquid level and the resistance value is: L = (R-R0) / (R1-R0)×(URV-LRV)+LRV; Wherein, R=resistance value of the fourth resistor×(V AIN0 -V AIN3 ) / (V AIN4 -V AIN0 ), V AIN0 is the voltage at the second end of the fourth resistor, V AIN4 is the voltage of the first end of the fourth resistor; V AIN3 is the voltage at the second end of the eighth resistor; R0 is the resistance value output by the magnetic flap liquid level device when the liquid level of the measured container is zero; R1 is the resistance value output by the magnetic flap liquid level device when the liquid level of the measured container is full; L is the current liquid level; LRV is the lowest liquid level value that the magnetic flap liquid level device can measure; URV is the highest liquid level value that the magnetic flap liquid level device can measure.

8. According to the magnetic flap level gauge based on APL technology as claimed in claim 1, it is characterized in that: in, The Ethernet communication module is connected to the microprocessor via a 4-wire serial peripheral interface SPI.

9. According to the magnetic flap level gauge based on APL technology as claimed in claim 1, it is characterized in that: Also includes: The power supply and reference circuit respectively supply power to the magnetic flap liquid level device, the analog-to-digital signal acquisition module, the microprocessor, the Ethernet communication module and the two-wire interface.

10. A magnetic flap liquid level detection system based on APL technology, characterized in that: include: A control device, used for sending a liquid level acquisition message, wherein the liquid level acquisition message includes a target IP address of a magnetic flap liquid level meter whose liquid level is to be acquired, and the structure of the magnetic flap liquid level meter is as described in claim 1; An APL power switch connected to the control device for receiving the liquid level collection message and sending the liquid level collection message to the APL field switch via industrial Ethernet; The APL field switch communicatively connected to the APL power switch is used to send the liquid level collection message to the magnetic flap level meter having the target IP address; A magnetic flap level gauge having the target IP address and communicating with the APL field switch via industrial Ethernet, and configured to send the acquired target signal to the APL field switch; The APL field switch is further used to feed back the target signal to the APL power switch; The APL power switch is also used to feed back the target signal to the control device.

Images