Electric leakage monitoring system and monitoring method of water meter

Abstract

The invention provides an electric leakage monitoring system and method for a water meter. The electric leakage monitoring system comprises a sampling resistor, a differential amplification circuit, a comparison circuit and a main controller. The sampling resistor is arranged between a power supply and a load and is used for acquiring a current signal; the differential amplification circuit is connected with the sampling resistor and is used for amplifying the current signal and then sending a voltage signal to the comparison circuit; the comparison circuit is connected with the differential amplification circuit and used for comparing the voltage signal with a preset threshold, and if the monitored voltage signal exceeds the preset threshold, a level signal is sent to the main controller; the main controller is connected with the comparison circuit, the main controller is in a dormant state, and the main controller is awakened and sends an alarm signal after receiving a level signal sent by the comparison circuit. The abnormal water meter can send out an alarm signal, so that maintenance personnel can quickly find the faulty water meter. Under normal conditions, the main controller is in a dormant state, and power consumption of the electric leakage monitoring system of the water meter is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of electronic water meters, and in particular to a leakage monitoring system and a monitoring method for a water meter. Background Art

[0002] Many water meters need to work in humid environments or even in water. In this case, it is inevitable that the internal circuit components of the water meter will be damp, which will increase the working current of the smart water meter and shorten the battery life. When a water meter leaks electricity, it needs to be repaired. How to find the leaking water meter among a large number of water meters is a major technical problem in the current smart water meter industry. If the one-by-one detection method is used, it will take a lot of time and economic expenditure. Summary of the invention

[0003] In order to solve the above technical problems, the present invention provides a leakage monitoring system for a water meter, which can realize leakage monitoring of a smart water meter and reduce power consumption during the monitoring process.

[0004] The specific technical scheme is as follows: A leakage monitoring system for a water meter includes a sampling circuit, a differential amplifier circuit, a comparison circuit and a main controller;

[0005] The sampling circuit is installed between the power supply and the load to obtain a current signal;

[0006] The differential amplifier circuit is connected to the sampling circuit and is used to send a voltage signal to the comparison circuit after amplification;

[0007] The comparison circuit is connected to the differential amplifier circuit and is used to compare the voltage signal with the preset threshold. If the monitored voltage signal exceeds the preset threshold, a level signal is sent to the main controller.

[0008] The main controller is connected to the comparison circuit and is in a dormant state. After receiving a level signal sent by the comparison circuit, the main controller is awakened and sends out an alarm signal.

[0009] Through the above technical solution, when leakage occurs or the current in the sampling circuit is too large, the amplified voltage signal exceeds the preset threshold of the comparison circuit, that is, a level signal is sent to the main controller to wake up the main controller, and the main controller sends an alarm signal to monitor whether there is an abnormality in the meter. Under normal conditions, the main controller is in a dormant state to save battery power consumption.

[0010] Preferably, a setting circuit is provided between the main controller and the comparison circuit, the setting circuit is connected to the main controller and the comparison circuit respectively, and the setting circuit is used to adjust a preset threshold of the comparison circuit.

[0011] Through the above technical solution, the preset threshold of the comparison circuit can be set by setting the circuit, so that the smart water meter can set different thresholds to adapt to leakage monitoring in different environments.

[0012] Preferably, the main controller is connected to a wireless transmission module, and the wireless transmission module is used to send an alarm signal to a user or a water supply station.

[0013] Through the above technical solution, the alarm signal can be sent to the user or the water supply station through the wireless transmission module.

[0014] Preferably, an RC delay circuit is connected between the differential amplifier circuit and the comparison circuit.

[0015] Through the above technical solution, the voltage signal state of the input comparison circuit can be made more stable through the RC delay circuit.

[0016] A monitoring method for a leakage monitoring system of a water meter comprises the following steps:

[0017] 1) The sampling circuit obtains the current signal between the power supply and the load and sends it to the differential amplifier circuit. At this time, the main controller is in a dormant state;

[0018] 2) amplifying the current signal through a differential amplifier circuit, and sending a voltage signal to a comparison circuit after amplification;

[0019] 3) The comparison circuit compares the voltage signal with the preset threshold value. If it exceeds the threshold value, a level signal is sent to the main controller;

[0020] 4) The main controller is awakened after receiving the level signal and sends out an alarm signal.

[0021] Through the above technical solution, the main controller can be put into a dormant state and will only be awakened and send an alarm signal when the current in the sampling circuit is too large, which effectively reduces the power consumption of the main controller and increases the operating time of the monitoring system.

[0022] Preferably, in step 2, the voltage signal is sent to the comparison circuit after passing through an RC delay circuit.

[0023] Through the above technical solution, the voltage signal input to the comparison circuit is made more stable, and the false awakening of the main controller by the comparison circuit is reduced.

[0024] The beneficial effects of the present invention are:

[0025] 1. Through hardware circuit self-diagnosis, abnormal water meters can send out alarm signals, making it easy for maintenance personnel to quickly find the problematic water meter, which can greatly save after-sales maintenance time and economic expenses.

[0026] 2. Under normal circumstances, the main controller is in sleep mode, which reduces the power consumption of the water meter leakage monitoring system.

[0027] 3. The main controller is connected to the wireless transmitter module, which can send alarms to users and water supply stations when the water meter operates abnormally. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative labor.

[0029] in:

[0030] Figure 1 This is a structural schematic diagram of Example 1;

[0031] Figure 2 This is the circuit diagram of Example 1; Figure 3 This is the circuit diagram of Example 2;

[0032] 1. Sampling circuit, 2. Differential amplifier circuit, 3. Comparison circuit, 4. Main controller, 5. Setting circuit, 6. RC delay circuit, 7. Wireless transmission module. DETAILED DESCRIPTION

[0033] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the drawings of the specification. In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention can also be implemented in other ways different from those described herein, and those skilled in the art can make similar generalizations without violating the connotation of the present invention, so the present invention is not limited by the specific embodiments disclosed below.

[0034] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0035] Example 1

[0036] like Figure 1As shown, a leakage monitoring system for a water meter includes a sampling circuit 1, a differential amplifier circuit 2, a comparison circuit 3 and a main controller 4. The sampling circuit 1 is installed between the power supply and the load, and is used to form a differential signal. The differential amplifier circuit 2 is connected to the sampling circuit, and is used to send a voltage signal to the comparison circuit after amplification. The comparison circuit 3 is connected to the differential amplifier circuit, and is used to compare the voltage signal with the preset threshold. If the detected voltage signal exceeds the preset threshold, a level signal is sent to the main controller 4. The main controller 4 is connected to the comparison circuit 3, and the main controller 4 is in a dormant state and can be awakened by the level signal sent by the comparison circuit 3. After being awakened by the level signal, the main controller 4 sends an alarm signal.

[0037] An RC delay circuit 6 is provided between the differential amplifier circuit 2 and the comparison circuit 3 .

[0038] A setting circuit 5 is provided between the main controller 4 and the comparison circuit 3 . The setting circuit 5 is connected to the main controller 4 and the comparison circuit 3 respectively. The setting circuit 5 is used to adjust a preset threshold of the comparison circuit 3 .

[0039] The main controller 4 is connected to the wireless transmitting module 7, and the wireless transmitting module 7 is used to send an alarm signal to the user or the water supply station.

[0040] Specifically, Figure 2 As shown, the sampling circuit 1 includes a sampling resistor R1. The differential amplifier circuit 2 adopts a differential amplifier U1, and the two input ends of the differential amplifier U1 are respectively connected to the lines at both ends of the resistor R1. The RC delay circuit 6 includes a second resistor R2 and a first capacitor C1, and the second resistor R2 is respectively connected to the differential amplifier U1 and the comparison circuit 3. One end of the first capacitor C1 is connected to the line between the second resistor R2 and the comparison circuit 3, and the other end is grounded. The comparison circuit 3 includes a third resistor R3, a fourth resistor R4, a fifth resistor R5 and a comparator U2. One end of the third resistor R3 is connected to the second resistor R2 through a line, and the other end is connected to one of the input ends of the comparator U2 through a line. One end of the fourth resistor R4 is connected to the line between the second resistor R2 and the comparator U2, and the other end is connected to the output end of the comparator U2 through a line. One end of the fifth resistor R5 is connected to the other input end of the comparator U2, and the other end is connected to the power supply. The main controller 4 adopts a controller U4 of the MSP430F2xxxx series. The serial digital-to-analog converter U3 used in the setting circuit 5 is MAX543x.

[0041] Example 2

[0042] The sampling circuit 1 includes a resistor R1 disposed between the power supply and the device, and the resistance value of R1 is 10Ω.

[0043] I=(V VBAT -V VDEC) / R1, and the total current is obtained. The differential amplifier circuit U6 uses the differential amplifier chip SGM8193, which converts (V VBAT -V VDEC ) is amplified by N times. The RS- terminal and RS+ terminal are electrically connected to the two ends of the resistor R1 respectively, and the OUT terminal is electrically connected to the RC delay circuit 6.

[0044] The RC delay circuit includes a resistor R33 and a capacitor C46. One end of the resistor R33 is electrically connected to the OUT terminal in the differential amplifier U6, and the other end is electrically connected to the comparison circuit. The resistance of the resistor R33 is 91KΩ; one end of the capacitor C46 is electrically connected to the circuit between the resistor R33 and the comparison circuit, and the other end is grounded. The capacitance of the capacitor C46 is 22μF 50V.

[0045] The comparison circuit includes a comparator U7, and the comparator U7 adopts SGM8701, wherein: a resistor R34 is connected in series between the IN+ terminal and the resistor R33, and the resistance of the resistor R34 is 20KΩ; the OUT terminal is electrically connected to the main controller 4, and is used to output a wake-up signal to the main controller 4; a resistor R35 is connected in parallel between the IN+ terminal and the OUT terminal, and the resistance of the resistor R35 is 20MΩ; a resistor R32 is connected in series between the IN- terminal and the ground, and the resistance of the resistor R32 is 200KΩ, and a capacitor C45 is connected in parallel to the resistor R32, and the capacitance of the capacitor C45 is 1nF 50V; a capacitor C43 is connected in series between the + terminal and the ground, and the capacitance of C43 is 0.1μF; the - terminal is grounded; and a setting circuit is connected between the IN- terminal and the + terminal.

[0046] The setting circuit includes a field effect tube connected to the + terminal. The field effect tube adopts AO3401. Its gate is connected in series with a resistor R30 and then connected to the main controller 4. The resistance of the resistor R30 is 10KΩ. The source is connected to a 3V power supply, and the drain is connected to the + terminal. A resistor R29 is connected in series between the 3V power supply and the resistor R30. The resistance of R29 is 3.3MΩ. The main controller 4 controls the voltage of the + terminal in the comparison circuit by controlling the field effect tube to set the voltage in the comparison circuit that is amplified N times (V VBAT -V VDEC ) is compared to a standard voltage.

[0047] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A water meter leakage monitoring system, characterized in that: It includes a sampling circuit, a differential amplifier circuit, a comparison circuit and a main controller; The sampling circuit is installed between the power supply and the load to obtain a current signal; The differential amplifier circuit is connected to the sampling circuit and is used to send a voltage signal to the comparison circuit after amplification; The comparison circuit is connected to the differential amplifier circuit and is used to compare the voltage signal with the preset threshold. If the monitored voltage signal exceeds the preset threshold, a level signal is sent to the main controller. The main controller is connected to the comparison circuit and is in a dormant state. After receiving a level signal sent by the comparison circuit, the main controller is awakened and sends out an alarm signal.

2. A water meter leakage monitoring system according to claim 1, characterized in that: A setting circuit is arranged between the main controller and the comparison circuit. The setting circuit is connected to the main controller and the comparison circuit respectively, and is used to adjust a preset threshold of the comparison circuit.

3. The leakage monitoring system for a water meter according to claim 1, characterized in that: The main controller is connected to a wireless transmission module, and the wireless transmission module is used to send an alarm signal to a user or a water supply station.

4. The leakage monitoring system for a water meter according to claim 1, characterized in that: An RC delay circuit is connected between the differential amplifier circuit and the comparison circuit.

5. A monitoring method for a leakage monitoring system of a water meter, characterized in that: The following steps are involved: 1) The sampling circuit obtains the current signal between the power supply and the load and sends it to the differential amplifier circuit. At this time, the main controller is in a dormant state; 2) amplifying the current signal through a differential amplifier circuit, and sending a voltage signal to a comparison circuit after amplification; 3) The comparison circuit compares the voltage signal with the preset threshold value. If it exceeds the threshold value, a level signal is sent to the main controller; 4) The main controller is awakened after receiving the level signal and sends out an alarm signal.

6. The monitoring method of the leakage monitoring system of a water meter according to claim 5, characterized in that: In step 2, the voltage signal is sent to the comparison circuit after passing through an RC delay circuit.

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