Tap water flow acquisition system

Abstract

A tap water flow acquisition system comprises a signal conversion module used for converting an RS232 signal into an RS485 signal, a power supply module electrically connected with the signal conversion module, a flow meter electrically connected with the signal conversion module, a PLC controller in communication connection with the signal conversion module, and a telemetering terminal in communication connection with the flow meter. The signal conversion module comprises an RS232 communication receiver, an RS232 protocol analyzer, a flow data acquisition module and a register, wherein the RS232 communication receiver is electrically connected with the flowmeter and used for monitoring and collecting signals of the flowmeter; the RS232 protocol analyzer is electrically connected with the RS232 communication receiver; the flow data acquisition module is electrically connected with the RS232 protocol analyzer and used for converting an RS232 protocol into a MODBUS RTU protocol; and the flow data acquisition module sends the communication protocol data stored in the register to the PLC through an RS485 wire mode.

Description

Technical Field

[0001] The utility model relates to the technical field of tap water treatment, in particular to a tap water flow acquisition system which converts RS232 signals into RS485 signals. Background Art

[0002] In the daily production and operation of water plants, flow measurement not only reflects water intake and supply conditions, but also provides a basis for diagnosing various indicators in the water treatment system, thereby effectively controlling water production operations and dosing. As the degree of automation in water plants continues to increase, the accuracy and stability of data collection from key data measurement instruments, especially large-caliber flow meters such as water plant inlet and outlet flow meters, are of great significance to the normal operation of water plants.

[0003] Currently, flow meters on the market are typically imported devices that use 4-20mA or MODBUS232 output signals as feedback signals for flow meter data. These signals are then transmitted as analog signals to the PLC controller in the waterworks control system. Traditional flow meters, when using analog data acquisition, cannot simultaneously collect both instantaneous and cumulative flow rates, making it difficult to meet the data needs of smart water management. Furthermore, the industry currently uses RS232 communication to transmit signals to telemetry terminals. This RS232 signal transmission to the PLC controller in the waterworks control system requires the PLC controller to be equipped with 232 serial communication capabilities. Flow data is obtained through online monitoring, data monitoring, analysis, and calculation. Signal reading is cumbersome and time-consuming to verify. If the original PLC controller does not have this serial communication capability, the data must be read by replacing or adding a new PLC controller. This high cost of adding a complete set of PLC equipment increases the management costs of the waterworks system. In addition, although some flow meters on the market with 485 communication functions can achieve long-distance and stable data transmission, the price of such instruments with communication functions is usually more expensive than that of instruments with 4-20mA and MODBUS232 output, which increases the hardware cost of the water plant. Utility Model Content

[0004] Based on this, it is necessary to address the above shortcomings and provide a tap water flow collection system that has stable signal transmission, can simultaneously take into account the instantaneous flow and cumulative flow collection of water, and has low hardware cost and converts RS232 signals into RS485 signals.

[0005] A tap water flow collection system includes a signal conversion module for converting RS232 signals into RS485 signals, a power module electrically connected to the signal conversion module, a flow meter electrically connected to the signal conversion module, a PLC controller communicatively connected to the signal conversion module, and a telemetry terminal communicatively connected to the flow meter. The signal conversion module includes an RS232 communication receiver electrically connected to the flow meter and used to monitor and collect flow meter signals, an RS232 protocol parser electrically connected to the RS232 communication receiver, a flow data collection module electrically connected to the RS232 protocol parser and used to extract flow meter data, and a register electrically connected to the flow data collection module. The flow data collection module sends the communication protocol data stored in the register to the PLC controller via an RS485 line.

[0006] In one embodiment, the power supply module is a 24V DC power supply.

[0007] In one embodiment, the signal conversion module also includes a power interface, a debugging interface, a monitoring interface and an output interface, the power interface is electrically connected to the power module, the RS232 communication receiver, the RS232 protocol parser and the flow data acquisition module respectively, the debugging interface is electrically connected to the RS232 communication receiver, the monitoring interface is electrically connected to the flow meter and the RS232 communication receiver respectively, the output interface is electrically connected to the flow data acquisition module, and the output interface is communicatively connected to the PLC controller.

[0008] In one embodiment, the output interface is communicatively connected to the PLC controller via a network cable or a signal cable.

[0009] In one embodiment, the telemetry terminal and the flow meter use master-slave communication, and an RS232 communication receiver is connected to the connection line between the telemetry terminal and the flow meter.

[0010] In implementing the tap water flow collection system of the present invention, a signal conversion module is set between the flow meter and the PLC controller. The signal conversion module converts the received RS232 signal of the flow meter into an RS485 signal, and transmits the collected flow information of the tap water system to the remote PLC controller through the communication protocol. The RS485 signal transmission under the converted MODBUS RTU protocol is stable, which ensures the stability and reliability of the flow signal collected by the PLC controller. The collection data type and data storage register address can be flexibly defined, which improves the accuracy of data collection in the water plant and improves the data collection efficiency; it can realize the collection of instantaneous and cumulative quantities of the flow meter, and can meet the needs of smart water services for multiple types of data; the flow collection system of this solution has lower cost, which reduces the hardware cost and manual debugging cost of the water plant. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 This is a schematic diagram of the module structure of a tap water flow collection system in one embodiment of the present utility model;

[0012] Figure 2 This is a wiring diagram of a tap water flow collection system in one embodiment of the present utility model;

[0013] Figure 3 It is a parameter setting, debugging and monitoring data interface of the signal conversion module in one embodiment of the present utility model;

[0014] Figure 4 This is a communication parameter setting diagram of a PLC controller in one embodiment of the present utility model;

[0015] Figure 5 This is a diagram of setting data acquisition parameters for a PLC controller in one embodiment of the present utility model;

[0016] Figure 6 This is a program diagram for analyzing and calculating data using a Siemens PLC controller. DETAILED DESCRIPTION

[0017] To make the above-mentioned objects, features, and advantages of the present invention more clearly understood, the following detailed description of specific embodiments of the present invention is provided in conjunction with the accompanying drawings. The following description sets forth many specific details to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways than those described herein, and those skilled in the art may make similar modifications without departing from the scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0018] Please combine Figure 1-2The present invention discloses a tap water flow collection system 10 that converts RS232 signals into RS485 signals, featuring stable signal transmission, capable of simultaneously collecting both instantaneous and cumulative water flow, and low hardware cost. The system comprises a signal conversion module 100 for converting RS232 signals into RS485 signals, a power module 200 electrically connected to the signal conversion module 100, a flow meter 300 electrically connected to the signal conversion module 100, a PLC controller 400 communicatively connected to the signal conversion module 100, and a telemetry terminal 500 communicatively connected to the flow meter 300. This system not only converts RS232 signals into RS485 signals and stably and reliably transmits them over long distances to the remote PLC controller 400, but also directly transmits the RS232 signals collected by the flow meter 300 to the user's telemetry terminal 500, thereby meeting the data type requirements for tap water flow management required by governments and other relevant management departments.

[0019] In this embodiment, the signal conversion module 100 includes an RS232 communication receiver 110 electrically connected to the flow meter 300 and used to monitor and collect flow meter 300 signals; an RS232 protocol analyzer 120 electrically connected to the RS232 communication receiver 110; a flow data acquisition module 130 electrically connected to the RS232 protocol analyzer 120 and used to extract flow meter data; and a register 140 electrically connected to the flow data acquisition module 130. The flow data acquisition module 130 transmits the communication protocol data stored in the register 140 to the PLC controller 400 via an RS485 line. The RS232 communication receiver 110 receives data transmitted based on the RS232 protocol. RS232 communication is a low-speed, single-ended serial communication method that uses an unbalanced transmission method and has poor common-mode interference immunity. Its maximum communication distance is only 15 meters, and it is limited to point-to-point communication. Its driver load is 3 to 7 kΩ, and it is primarily suitable for communication between local devices, such as to meet signal transmission between the local telemetry terminal 500 and the flow meter 300. The RS232 protocol parser 120 is used to parse and split signals transmitted via the RS232 protocol to obtain instantaneous flow data and cumulative flow data from the flow meter 300. Further preferably, master-slave communication is employed between the telemetry terminal 500 and the flow meter 300, and the RS232 communication receiver 110 is connected to the connection line between the telemetry terminal 500 and the flow meter 300. Thus, when the flow meter 300 transmits the instantaneous flow signal and the cumulative flow signal to the telemetry terminal 500, the RS232 communication receiver 110 receives both signals, and the RS232 protocol parser 120 converts the two RS232 signals into corresponding data signals. The flow data acquisition module 130 is used to collect flow data from the data parsed and split by the RS232 protocol parser 120, and the collected data constitutes MODBUS RTU communication protocol data. In this embodiment, the flow data collection module 130 may be a combination of a filter and a voltage / current sensor, so that the flow data collection module only collects the flow data from the data parsed by the RS232 protocol parser 120 .

[0020] During the liquid flow collection process in the waterworks management system, the flowmeter 300 collects the instantaneous flow rate and accumulated flow rate signals of the liquid in the pipeline. When powered by the power module 200, the flowmeter 300 transmits these signals to the telemetry terminal 500 in the form of RS232 signals. Simultaneously, the RS232 communication receiver 110 monitors and receives the RS232 signal transmitted from the flowmeter 300 to the telemetry terminal 500. This signal is then transmitted to the RS232 protocol parser 120, which parses and decomposes the flow data transmitted by the RS232 communication receiver 110. The flow data collection module 130 then collects the flow data and assembles it into MODBUS RTU communication protocol data as new protocol data. The flow data collection module 130 then retrieves the new protocol data from the register 140 and transmits it to the PLC controller 400 via RS485 wiring. This allows for simultaneous data type conversion while also enabling the collection and long-distance transmission of instantaneous and accumulated flow data.

[0021] The aforementioned tap water flow collection system 10 includes a signal conversion module 100 within the flow meter 300 and the PLC controller 400, which converts RS232 data into RS485 signals capable of data collection via the Modbus RTU protocol. The collected flow information of the tap water system is then transmitted to the remote PLC controller 400 via communication. The stable RS485 signal transmission under the Modbus RTU protocol ensures the stability and reliability of the flow signal collected by the PLC controller 400, thereby improving the accuracy of data collection at the water plant. This system allows for simultaneous collection of instantaneous and cumulative flow without replacing the flow meter 300. While meeting the diverse data needs of smart water services, data collection types and formats can be flexibly defined, resulting in highly efficient reading without the need for analytical calculations. Compared to direct PLC monitoring and analytical calculations, this flow collection system offers lower costs and higher reading efficiency, reducing hardware and manual commissioning costs for water plants. During long-distance transmission, RS485 signals replace RS232 signals, reducing data instability issues caused by RS232 signal transmission. This makes system operation more stable and reliable, better meeting the construction requirements of today's automated and intelligent water plants. Furthermore, the signal conversion module 100 converts the monitored flow meter 300 signal into RS485 communication format data, which is then read by the PLC controller 400 and transmitted to the water plant's host computer control system. This enables point-to-multipoint master-slave communication, ensuring long-distance, stable transmission of flow signals.

[0022] In this embodiment, the signal conversion module 100 is used to read RS232 data. Using an on-site PLC substation or replacing the PLC controller 400 would cost 10,000 yuan, and the analytical calculations, program conversion, and testing would take at least a week, with manual commissioning costs of approximately 2,000 yuan. Replacing the flowmeter 300 to read data, for example, would cost approximately 200,000 yuan for a DN800 raw water flowmeter. For a water plant with a production capacity of 60,000 tons per day, the entire management system would use approximately three large-diameter flowmeters 300. Using this solution, only three corresponding signal conversion modules 100 would be required, each costing approximately 1,000 yuan. In summary, compared with the method of directly parsing data by the PLC controller 400, the adoption of this solution can save about 3x(10000+2000)-3x1000=33000 yuan; compared with the method of replacing the flow meter 300, it can save 3x200000-3x1000=597000 yuan, which significantly saves the hardware cost of the water plant.

[0023] In one embodiment, the power module 200 is a 24V DC power supply, which is used to provide a 24V low-voltage DC voltage for the normal operation of the signal conversion module 100. The signal conversion module 100 also includes a power interface 150, a debugging interface 160, a monitoring interface 170, and an output interface 180. The power interface 150 is electrically connected to the power module 200, the RS232 communication receiver, the RS232 protocol analyzer, and the flow data acquisition module 130. The debugging interface is electrically connected to the RS232 communication receiver. The monitoring interface 170 is electrically connected to the flow meter 300 and the RS232 communication receiver 110. The output interface 180 is electrically connected to the flow data acquisition module 130 and is communicatively connected to the PLC controller 400. Further preferably, the output interface 180 is communicatively connected to the PLC controller 400 via a network cable or a signal cable. In this embodiment, the debugging interface 160 is used to access the RS232 signal of the analog flow meter 300 signal and perform debugging before the system is operated, so as to ensure the reliability of the tap water flow collection system 10.

[0024] Please combine Figure 4-5 Before collecting the tap water flow through the above system, the parameters of the PLC controller 400 need to be set. Specifically, the parameters required for the PLC controller 400 to read data need to be set, including baud rate, data bit, wiring method, data stop bit, parity bit, communication time, etc. The parameters must be consistent with the instrument end (such as Figure 4The communication station address, data address and final data storage address corresponding to each flow meter 300 are set on the PLC controller 400 so that the PLC controller 400 can receive the flow data transmitted from each flow meter 300 via the corresponding signal conversion module 100 (as shown); Figure 5 shown).

[0025] Please combine Figure 3 and Figure 6 , Figure 3 By setting the data type, the address of the register 140 of the signal conversion module 100 can be directly read to read the instantaneous and cumulative flow signals; Figure 6 Through the newly added Siemens PLC controller 400 monitoring and collecting flow meter 300 RS232 signal program, we can see that the program has about 60 lines and is very cumbersome to parse. It requires transfer, calculation, and continuous observation and comparison to verify the accuracy of the data. This approach is complicated and cannot effectively determine the accuracy of the data. Figure 3 The data is directly read through the signal conversion module 100, and the data can be directly observed in the debugging interface to see whether it is consistent with the on-site flow meter 300. The flow data collected by the system of this solution is more efficient and reliable, and can realize the simultaneous collection of instantaneous flow and cumulative flow data to meet the water data management needs of the water plant.

[0026] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0027] The above-described embodiments merely represent several implementations of the present invention. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the utility model patent. It should be noted that a person skilled in the art would be able to make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements fall within the scope of protection of the present invention. Therefore, the scope of protection of the present utility model patent shall be determined by the appended claims.

Claims

1. A tap water flow collection system, characterized in that: It includes a signal conversion module for converting RS232 signals into RS485 signals, a power module electrically connected to the signal conversion module, a flow meter electrically connected to the signal conversion module, a PLC controller communicatively connected to the signal conversion module, and a telemetry terminal communicatively connected to the flow meter. The signal conversion module includes an RS232 communication receiver electrically connected to the flow meter and used to monitor and collect flow meter signals, an RS232 protocol parser electrically connected to the RS232 communication receiver, a flow data acquisition module electrically connected to the RS232 protocol parser and used to extract flow meter data, and a register electrically connected to the flow data acquisition module. The flow data acquisition module sends the communication protocol data stored in the register to the PLC controller via the RS485 line.

2. The tap water flow collection system according to claim 1, characterized in that: The power supply module is a 24V DC power supply.

3. The tap water flow collection system according to claim 1, characterized in that: The signal conversion module also includes a power interface, a debugging interface, a monitoring interface and an output interface. The power interface is electrically connected to the power module, the RS232 communication receiver, the RS232 protocol parser and the flow data acquisition module respectively. The debugging interface is electrically connected to the RS232 communication receiver. The monitoring interface is electrically connected to the flow meter and the RS232 communication receiver respectively. The output interface is electrically connected to the flow data acquisition module, and the output interface is communicatively connected to the PLC controller.

4. The tap water flow collection system according to claim 3, characterized in that: The output interface is connected to the PLC controller via a network cable or a signal cable.

5. The tap water flow collection system according to claim 1, characterized in that: The telemetry terminal and the flow meter adopt master-slave communication, and the RS232 communication receiver is connected to the connection line between the telemetry terminal and the flow meter.

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