A mobile water meter electromagnetic compatibility real-flow calibration device and calibration method thereof

Abstract

The present invention discloses a mobile electromagnetic compatibility real-flow calibration device and calibration method for water meters. The calibration device includes a mobile platform, a refrigerator, a water storage tank, a liquid-filling pump, an air bag tank, and a standard meter. The water inlet and outlet of the refrigerator are connected to the water storage tank, the liquid inlet of the liquid-filling pump is connected to the water storage tank via a first pipeline, and the liquid outlet of the liquid-filling pump is divided into a connection between the air bag tank and the standard meter via a liquid outlet pipe; the water outlet of the standard meter is connected to the water storage tank. The calibration device is moved to the vicinity of the electromagnetic compatibility test equipment using the mobile platform, and the water meter to be tested is placed on the sample platform and connected to the calibration device via a hose. The data of the standard meter and the water meter to be tested are recorded respectively before and after the disturbance conditions are applied. The present invention adopts the design of the air bag tank and the standard meter, which reduces the volume of the calibration device and solves the problem of asynchronous disturbance conditions and measurement. The readings of the water meter to be tested are read using machine vision technology, which improves the intelligence level of the entire test process.

Description

Technical Field

[0001] The invention relates to a mobile water meter electromagnetic compatibility real-flow calibration device and a calibration method thereof. Background Art

[0002] According to the requirements of JJF 1777-2019 "Outline for Type Evaluation of Drinking Cold Water Meters", electronic water meters should undergo electromagnetic compatibility real-flow tests, including AC voltage sag and short-time interruption tests, pulse group immunity tests, electrostatic discharge immunity tests, radiated electromagnetic field immunity tests, conducted electromagnetic field immunity tests and surge immunity tests. The test procedure is: before applying the specified disturbance conditions, measure the indication error of the water meter through the water meter calibration device; generate the specified disturbance conditions through the electromagnetic compatibility test equipment and apply them to the water meter, and at the same time measure the indication error of the water meter on the water meter calibration device; calculate the deviation and check the normality of various functions of the water meter.

[0003] During the test, the electromagnetic compatibility test equipment is generally placed near the water meter calibration device, or the water meter calibration device is moved near the electromagnetic compatibility test equipment. In order to ensure flow stability, existing water meter calibration devices usually use a container pressure stabilization method, which requires a large pressure stabilizing tank. Water enters from one side of the pressure stabilizing tank and flows out from the other side. The pressure stabilizing tank can buffer pressure fluctuations and ensure water pressure stability; the main standard is generally a working volume meter or a weighing container. During the calibration process, the liquid flowing through the water meter needs to be collected to obtain the standard value in a static state. The above-mentioned water meter calibration device can basically meet the test requirements, but there are also the following problems:

[0004] 1. Inconvenient to move. To achieve ideal flow stability, the water meter calibration device using the container pressure stabilization method requires a large pressure stabilizing tank. During the test, the medium is collected in the main standard device. Therefore, the designed water tank capacity must be greater than the sum of the volumes of the pressure stabilizing tank and the main standard device. Therefore, the above-mentioned water meter calibration device is a fixed set of equipment, which is generally large and difficult to move. The radiated electromagnetic field test equipment in the electromagnetic compatibility test project is a set of independent, fixed test systems and cannot be moved.

[0005] 2. The synchronization between disturbance conditions and measurement is difficult to ensure. The size of the main standard in a water meter calibration device using the collection method is generally designed to accommodate the device's maximum flow rate for one minute. However, the disturbance conditions generated by the radiated and conducted electromagnetic fields can last for more than one minute, resulting in an asynchrony phenomenon where the calibration process has already completed before the applied disturbance conditions have ended.

[0006] 3. Weak intelligence: The test cycle for radiated electromagnetic fields and conducted electromagnetic fields generally takes more than one hour. If traditional manual testing is continued, the work efficiency will be extremely low, and automatic reading and recording will not be possible. Summary of the Invention

[0007] In order to solve the above problems, the present invention proposes a mobile water meter electromagnetic compatibility real-flow calibration device and a calibration method based on machine vision.

[0008] The present invention achieves the above-mentioned purpose by adopting the following technical solutions:

[0009] In one aspect, the present invention provides a mobile electromagnetic compatibility (EMC) real-flow calibration device for water meters, comprising a mobile platform, a refrigerator, a water tank, a dosing pump, an airbag tank, a standard meter, and a machine vision measurement device. The mobile platform is equipped with universal wheels. The water inlet and outlet of the refrigerator are connected to the water tank, forming a circulation loop. The liquid inlet of the dosing pump is connected to the water tank via a first pipeline. The liquid outlet of the dosing pump is divided into two paths via a liquid outlet pipe: one path connects to the airbag tank, and the other path connects to the standard meter. The water outlet of the standard meter is connected to the water tank.

[0010] The air bag tank contains an air bag and a water bag. The water bag is connected to the second pipeline through a tee. The second pipeline is provided with a water inlet valve, a pressure gauge and a thermometer.

[0011] The water meter to be tested is connected to the second pipeline and the third pipeline respectively through the first hose and the second hose.

[0012] The third pipeline is provided with a regulating valve and a stop valve, and the third pipeline is provided with a standard meter; the standard meter is connected with the water tank through the fourth pipeline.

[0013] The water meter being tested is equipped with a machine vision measuring device for automatically recording the volume indicated by the water meter being tested.

[0014] The refrigerator, water storage tank, liquid adding pump, air bag tank and standard meter are all placed on a mobile platform.

[0015] The water meter to be tested is placed on a sample platform of electromagnetic compatibility testing equipment.

[0016] The standard meter is an electromagnetic flowmeter.

[0017] In one aspect, the present invention provides a calibration method for a mobile water meter electromagnetic compatibility real-flow calibration device, comprising the following steps:

[0018] 1) Mobile devices

[0019] First, use a mobile platform to move the entire calibration device to the vicinity of the corresponding electromagnetic compatibility test equipment. Place the water meter under test and the machine vision measurement device on the sample platform of the electromagnetic compatibility test equipment, and connect the water meter under test to the calibration device through a hose.

[0020] 2) Flow pre-adjustment

[0021] Start the liquid storage pump, air bag tank and refrigerator, and the liquid enters the air bag tank and the second pipeline through the three-way valve. During this period, the water inlet valve, stop valve and regulating valve are opened, and the pipeline system is circulated with water. The compressed air in the air bag tank is used to stabilize the flow rate, so that the calibration device maintains good flow stability. The pressure gauge and thermometer are used to monitor the water pressure and temperature in the pipeline. The regulating valve is used to adjust the liquid flow rate. The standard meter is used to indicate the current reference flow value and the measurement master standard of the pipeline system. The flow rate is pre-adjusted to the specified flow value through the regulating valve;

[0022] 3) Apply disturbance conditions to complete measurement calibration

[0023] The electromagnetic compatibility test equipment is controlled to generate the specified disturbance conditions, and the initial data of the standard meter and the water meter under test are recorded at the same time; when the disturbance conditions of the electromagnetic compatibility test equipment end, the termination data of the standard meter and the water meter under test are recorded at the same time; the machine vision measurement device is used to record the initial and termination data of the water meter under test, and the standard meter records the standard data during a measurement process. The test duration can be controlled according to the duration of the applied disturbance conditions to ensure the synchronization of the disturbance conditions and the measurement.

[0024] The present invention has the following beneficial effects: The design of an airbag tank and a standard meter reduces the volume of the entire calibration apparatus. This not only meets the requirement for flow stability, but also eliminates the need for a collection method master standard, resolving the issues of disturbance conditions and measurement asynchrony during the test. The use of machine vision technology to record the meter readings improves the intelligence of the entire test process and enhances detection efficiency compared to manual reading. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a structural schematic diagram of the electromagnetic compatibility real-flow calibration device for a mobile water meter of the present invention.

[0026] In the figure: 1-universal wheel; 2-mobile platform; 3-liquid filling pump; 4-air bag tank; 5-refrigeration machine; 7-water inlet valve; 8-pressure gauge; 9-thermometer; 10-tested water meter; 11-stop valve; 12-regulating valve; 13-standard meter; 14-second hose; 15-first hose; 16-machine vision measurement device; 17-water tank. DETAILED DESCRIPTION

[0027] The present invention will be further described below with reference to the accompanying drawings.

[0028] Example 1

[0029] like Figure 1 As shown, the mobile water meter electromagnetic compatibility real-flow calibration device described in the present invention includes a mobile platform 2, a refrigerator 5, a water storage tank 17, a liquid adding pump 3, an air bag tank 4, a standard meter 13 and a machine vision measurement device 16.

[0030] The mobile platform 2 is equipped with universal wheels 1 for movement of the entire device. The water inlet and outlet of the refrigerator 5 are connected to the water tank 17 to form a circulation loop. The liquid inlet of the liquid charging pump 3 is connected to the water tank 17, and the liquid outlet of the liquid charging pump 3 is divided into two paths through a liquid outlet pipe: one path is connected to the air bag tank 4, and the other path is connected to the standard meter 13. The water outlet of the standard meter 13 is connected to the water tank 17.

[0031] The liquid outlet pipe is equipped with a water meter 10 to be calibrated, a thermometer 9 for measuring the temperature of the liquid in the pipe, a pressure gauge 8 for measuring the pressure of the liquid in the pipe, an inlet valve 7 for switching the flow of the liquid in the pipe, a regulating valve 12 and a stop valve 11 for regulating the flow of the liquid in the pipe; a machine vision measurement device 16 is installed above the water meter 10 to automatically record the indicated volume of the water meter.

[0032] The liquid inlet of the liquid adding pump 3 is connected to the water tank 17 through a first pipeline, and the air bag tank 4 is connected to the second pipeline through a tee. The second pipeline is sequentially installed with an inlet valve 7, a pressure gauge 8 and a thermometer 9. The measured water meter 10 is connected to the second pipeline and the third pipeline through a first hose 15 and a second hose 14 respectively; the third pipeline is sequentially installed with a stop valve 11, a regulating valve 12 and a standard meter 13, and the standard meter 13 is used to indicate instantaneous flow and measurement; the standard meter 13 is connected to the water tank 17 through a fourth pipeline.

[0033] The refrigerator 5 , water storage tank 17 , liquid adding pump 3 , air bag tank 4 , standard meter 13 and pipeline system are all placed on the mobile platform 2 .

[0034] The water meter 10 to be tested is placed on a sample platform of an electromagnetic compatibility test device.

[0035] The standard meter 13 adopts an electromagnetic flowmeter.

[0036] Example 2

[0037] The calibration method of the mobile water meter electromagnetic compatibility real-flow calibration device according to embodiment 1 includes the following steps:

[0038] 1) Mobile devices

[0039] First, use the mobile platform 2 to move the entire calibration device to the vicinity of the corresponding electromagnetic compatibility test equipment, place the water meter 10 to be tested and the machine vision measurement device 16 on the sample platform of the electromagnetic compatibility test equipment, and connect the water meter 10 to the calibration device through the first hose and the second hose.

[0040] 2) Flow pre-adjustment

[0041] Start the liquid adding pump 3, air bag tank 4 and refrigerator 5, and the liquid enters the air bag tank 4 and the second pipeline through the three-way valve. During this period, the water inlet valve 7, the stop valve 11 and the regulating valve 12 are opened, and the pipeline system is circulated with water. The compressed air in the air bag tank 4 is used to stabilize the flow rate, so that the calibration device maintains good flow stability. The pressure gauge 8 and the thermometer 9 are used to monitor the water pressure and water temperature on the pipeline. The standard meter 13 is used to indicate the current reference flow value of the pipeline system and serve as the main measurement standard. The regulating valve 12 is used to adjust the liquid flow rate, and the flow rate is pre-adjusted to the specified flow value through the regulating valve 12.

[0042] 3) Apply disturbance conditions to complete measurement calibration

[0043] The electromagnetic compatibility test equipment is controlled to generate specified disturbance conditions. The start time is when the disturbance parameters begin to be applied to the water meter under test. The initial data of the standard meter 13 and the water meter under test 10 are simultaneously recorded. The end time is when the disturbance parameters of the electromagnetic compatibility test equipment end. The final data of the standard meter 13 and the water meter under test 10 are again recorded simultaneously. The initial and final data of the water meter under test 10 are recorded by the machine vision measurement device 16. The indicated volume of the water meter under test is obtained through calculation. The standard meter 13, acting as a measurement standard, records the initial and final data of a measurement process. The actual volume of the standard is obtained through calculation.

[0044] The test duration can be controlled according to the duration of the applied disturbance conditions to ensure the synchronization of the disturbance conditions and measurement.

[0045] In summary, the present invention adopts an air bag tank as the pressure stabilizing system, which has smaller space requirements than a pressure stabilizing tank and has the same function as a pressure stabilizing tank in ensuring flow stability. When the water pressure changes, the expansion and contraction of the air bag plays a damping role; the standard meter method is used as the main standard instrument, and during the calibration process, there is no need to collect the liquid flowing through the water meter, thereby reducing the volume of the water tank and there is no limit on the calibration time; machine vision technology is used instead of manual reading to realize the automation of the calibration device.

[0046] The contents described in the embodiments of this specification are merely an enumeration of the implementation forms of the inventive concept. The scope of protection of the present invention should not be regarded as limited to the specific forms described in the embodiments. The scope of protection of the present invention also includes equivalent technical means that can be thought of by those skilled in the art based on the inventive concept.

Claims

1. A mobile water meter electromagnetic compatibility real-flow calibration device, characterized by: Includes mobile platform, refrigerator, water storage tank, liquid filling pump, air bag tank, standard table and machine vision measurement device; The mobile platform is provided with universal wheels; The water inlet and outlet of the refrigerator are connected to the water tank; the liquid inlet of the liquid adding pump is connected to the water tank through a first pipeline, and the liquid outlet of the liquid adding pump is divided into two paths through a liquid outlet pipe, one path is connected to the air bag tank, and the other path is connected to the standard meter; the standard meter is connected to the water tank through a fourth pipeline; The air bag tank contains an air bag and a water bag in the tank body, and the water bag is connected to the second pipeline through a tee; the standard meter is set in the third pipeline; the tested water meter is installed between the second pipeline and the third pipeline; The refrigerator, water storage tank, liquid adding pump, air bag tank and standard meter are all placed on a mobile platform; A machine vision measuring device is provided above the water meter being measured, for automatically recording the indicated volume of the water meter being measured.

2. The mobile water meter electromagnetic compatibility real-flow calibration device according to claim 1, characterized in that: The two ends of the water meter to be tested are connected to the second pipeline and the third pipeline through a hose.

3. The mobile water meter electromagnetic compatibility real-flow calibration device according to claim 1, characterized in that: The standard meter is an electromagnetic flowmeter.

4. The mobile water meter electromagnetic compatibility real-flow calibration device according to claim 1, characterized in that: The second pipeline is provided with a water inlet valve, a pressure gauge and a thermometer; the third pipeline is provided with a regulating valve and a stop valve.

5. A mobile water meter electromagnetic compatibility real-flow calibration method, using the mobile water meter electromagnetic compatibility real-flow calibration device according to any one of claims 1 to 4, characterized in that The following steps are involved: 1) Mobile devices: First, the entire calibration device is moved to the vicinity of the corresponding electromagnetic compatibility test equipment using a mobile platform. The water meter under test and the machine vision measurement device are placed on the sample platform of the electromagnetic compatibility test equipment. The water meter under test is connected to the calibration device through a hose. 2) Flow pre-adjustment: The liquid adding pump, the air bag tank and the refrigerator are started, the liquid enters the air bag tank and the second pipeline, the water inlet valve, the stop valve and the regulating valve are opened, and the pipeline system is circulated with water; the compressed air in the air bag tank is subjected to flow and pressure stabilization, the pressure gauge and the thermometer monitor the water pressure and temperature on the pipeline, the standard meter measures the current reference flow value of the pipeline system, and the flow is pre-adjusted to the specified flow value through the regulating valve; 3) Apply disturbance conditions to complete metrological calibration: Control the disturbance conditions generated by the electromagnetic compatibility test equipment, take the time when the disturbance conditions begin to be applied to the water meter under test as the starting time, and simultaneously record the initial data of the standard meter and the water meter under test; The end time is when the disturbance condition of the electromagnetic compatibility test equipment ends, and the termination data of the standard meter and the tested water meter are recorded at the same time.

Images