Automatic calibration tool, method and system for electromagnetic flowmeter converter

Abstract

The invention discloses an automatic calibration tool, method and system for an electromagnetic flowmeter converter, the calibration system comprises a calibration tool and a calibration unit, the upper part of a main body box of the calibration tool is provided with a recessed base, the base is provided with a base thimble, and two sides of the base are provided with a baffle plate and a push plate; the distance between the push plate and the baffle is adjusted through a sliding rod, and the push plate is provided with an excitation and signal ejector pin block on the side of the base. In the calibration unit, an excitation ejector pin and a signal ejector pin are connected with an excitation current input terminal and a flow signal output terminal of a flow signal module respectively, an excitation current detection module is connected with the flow signal module so as to detect the magnitude of input excitation current, and a communication module obtains data of the electromagnetic flowmeter. The upper computer communication interface uploads the calibration result and the detection data to an upper computer; the calibration and calibration method comprises the steps that the electromagnetic flowmeter converter is installed on the calibration tool, and calibration and calibration are conducted on the electromagnetic flowmeter converter through the calibration and calibration system.

Description

Technical Field

[0001] This invention belongs to the field of electromagnetic converter calibration and testing technology, specifically relating to an automated calibration and testing fixture, method and system for electromagnetic flowmeter converters. Background Technology

[0002] Electromagnetic flowmeters are widely used in petrochemical, wastewater treatment, food, and pharmaceutical industries. An electromagnetic flowmeter consists of two interconnected parts: an electromagnetic flowmeter sensor and an electromagnetic flowmeter converter. The electromagnetic flowmeter sensor converts the volumetric flow rate of the fluid into an induced electromotive force signal, while the electromagnetic flowmeter converter amplifies this signal and converts it into a standard electrical signal output. The accuracy of the electromagnetic flowmeter converter directly affects production efficiency and resource management. Currently, most electromagnetic converter calibrations in the industry use handheld signal sources. This involves connecting the signal source and the electromagnetic converter, powering it on, and manually rotating the flow rate switch of the signal source for calibration. This method is extremely inefficient, prone to human error, requires manual intervention each time the switch is rotated, and lacks integrated thermal resistance calibration in the tooling hardware, necessitating a separate external precision resistance box for manual calibration. Furthermore, it does not support data recording during calibration and testing, making traceability impossible. Summary of the Invention

[0003] To address the shortcomings of existing technologies and achieve the goals of improving calibration and testing accuracy and increasing production efficiency, this invention adopts the following technical solution:

[0004] An automated calibration fixture for an electromagnetic flowmeter converter includes a main body and a clamping mechanism. The main body has a recessed base on its upper part, and a base pin is provided on the base. The clamping mechanism includes a baffle and a push plate respectively disposed on both sides of the base. The distance between the push plate and the baffle is adjusted by a sliding rod. The push plate has an excitation and signal pin block on the base side. The base pin is configured to cooperate with the bottom of the electromagnetic flowmeter converter's core to quickly fix the core onto the base pin. The excitation and signal pin block is configured to cooperate with a terminal on one side of the core.

[0005] Furthermore, the baffles and push plates on the left and right sides of the base are respectively provided with corresponding lateral limiting blocks, and the front and rear sides of the base are respectively provided with longitudinal limiting blocks. The longitudinal limiting blocks and lateral limiting blocks are configured to cooperate with the outer periphery of the movement to fix the position of the movement.

[0006] Furthermore, the push plate is provided with a push rod assembly on the other side of the base, and the push plate can be laterally slid along the slide bar relative to the baffle by pulling the push rod assembly.

[0007] An automated calibration system for an electromagnetic flowmeter converter includes a calibration fixture and a calibration unit. The calibration fixture is the aforementioned automated calibration fixture for an electromagnetic flowmeter converter. The calibration unit includes a control module and a power supply module, an excitation current detection module, a flow signal module, a communication module, and a host computer communication interface, all connected to the control module. The base pins of the calibration fixture are connected to the control module and the power supply module. The excitation and signal pin blocks are connected to the flow signal module, so that the excitation pins of the excitation and signal pin blocks are connected to the excitation current input terminal of the flow signal module via wires, and the signal pins of the excitation and signal pin blocks are connected to the flow signal output terminal of the flow signal module. The excitation current detection module is connected to the flow signal module and is used to detect the magnitude of the input excitation current. The communication module acquires electromagnetic flowmeter data, and the host computer communication interface uploads the calibration results and detection data to the host computer.

[0008] Furthermore, the excitation current detection module has a built-in ADC sampling function, which is used to detect the magnitude and excitation frequency of the electromagnetic flowmeter excitation current simulated by the flow signal module.

[0009] Furthermore, the flow signal module uses a resistor network to simulate the electromagnetic sensor and fluid medium used in a real electromagnetic flow meter. Different resistance ratios represent the flow rate of the fluid in the pipe. The flow signal can be obtained simply by acquiring the excitation current, which simplifies the cost. Moreover, because it is constructed using resistors, the flow signal module is very stable and will not produce errors like electromagnetic sensors and fluids in actual use.

[0010] Furthermore, the control module is also connected to a resistance temperature detector (RTD) module, a clock, a HART communication module, a 4-20mA detection module, a pulse detection module, and a switch quantity alarm output detection module;

[0011] The thermal resistance module uses a precision resistor with a four-wire output to calibrate and test the thermal resistance function of the electromagnetic flow converter.

[0012] The HART communication module is used to realize the HART communication function with the electromagnetic flowmeter;

[0013] The 4-20mA detection module uses a high-precision, low-temperature drift precision resistor as the sampling resistor, and simulates a 24-bit ADC chip to acquire and convert 4-20mA, with a sampling resolution of up to 1uA.

[0014] The pulse detection module uses an internal timer of the control module to count pulses / frequency.

[0015] The switch alarm output detection module uses the general-purpose I / O port of the control module to detect high and low levels.

[0016] An automated calibration method for an electromagnetic flowmeter converter, employing the aforementioned automated calibration system for an electromagnetic flowmeter converter, includes the following steps:

[0017] Step S1: Install the electromagnetic flowmeter converter onto the calibration fixture;

[0018] Step S2: Perform calibration and verification of the electromagnetic flowmeter converter using the automated calibration and verification system;

[0019] Step S2 specifically includes the following steps:

[0020] Step S2.1: Open the host computer software, click Start to enter automatic calibration. The host computer software reads the electromagnetic flowmeter converter information (such as model) through the host computer communication interface via communication commands.

[0021] Step S2.2: Based on the electromagnetic flowmeter converter information, automatically perform converter excitation, signal, and output function calibration;

[0022] The electromagnetic flowmeter outputs excitation current to the flow signal module through the excitation pin, and then the signal pin obtains flow data (voltage value) from the flow signal module. The calibration command is issued through the communication module. The electromagnetic flowmeter continuously obtains flow data within a certain period of time and calculates the average value. This average value is used as the standard flow data, and the calibration coefficient related to the hardware of each electromagnetic flowmeter is calculated. After all electromagnetic flowmeters are calibrated by the same calibration fixture or the same series of calibration fixtures that meet the accuracy requirements, the error between hardware is eliminated, and the calibration is completed.

[0023] The core formula of an electromagnetic flowmeter:

[0024] E=KBdv

[0025] Where E represents the signal voltage between the electrodes, K represents the normalization coefficient of the converter (i.e., a coefficient related to the magnetic field distribution and the axial length of the sensor), B represents the magnetic flux density, d represents the inner diameter of the measuring tube, and v represents the average flow velocity. Since the excitation current is constant, B is a constant.

[0026] Step S2.3: After calibration, the calibration system automatically tests various functions of the electromagnetic flowmeter converter and determines various indicators of the electromagnetic converter based on the test results;

[0027] Step S2.4: The calibration results and test data are uploaded through the host computer communication interface, automatically uploaded to a local or remote server, and can be queried by logging in through the host computer software.

[0028] Further, step S1 specifically includes the following steps:

[0029] Step S1.1: Pull the push rod to the right so that the bottom of the core of the electromagnetic flowmeter converter is connected to the base through the base pin, and connected to the control board and power cord through the base pin, realizing quick connection of the electromagnetic converter core without manual wiring and reducing wiring failures;

[0030] Step S1.2: Push the push rod to the left so that the excitation and signal pin block on the push plate is connected to the excitation and signal terminals of the mechanism. At the same time, the mechanism is limited in the horizontal direction by the longitudinal limit block and the transverse limit block. In fact, the base pin at the bottom of the mechanism and the excitation and signal pin block on the side also play a role in limiting the horizontal and vertical directions to a certain extent.

[0031] Furthermore, the control module is also connected to a resistance temperature detector (RTD) module, a clock, a HART communication module, a 4-20mA detection module, a pulse detection module, and a switch alarm output detection module. The detection in step S2.3 includes the following steps:

[0032] Step S2.3.1: The calibration fixture obtains excitation current (current) through the excitation pin and enters the flow signal module. After the excitation current flows into the flow signal module, a flow signal (voltage) is generated on the signal pin and output to the electromagnetic flow meter. The control module can be controlled through the host computer communication interface to switch the speed of the flow signal module to generate different flow signals (voltages). The flow rate of the electromagnetic flow meter is read through the communication module to detect whether the flow function of the electromagnetic flow meter is normal.

[0033] Step S2.3.2: Excitation current detection; The calibration fixture measures the excitation current value output from the electromagnetic flowmeter to the flow signal module through the excitation current detection module, and compares it with the theoretical excitation current (determined by hardware and input before calibration detection);

[0034] Step S2.3.3: Resistance Temperature Detection; The electromagnetic flowmeter outputs a current signal to the resistance temperature module of the calibration fixture through the pin of the calibration fixture base, and then obtains a voltage signal through the pin to sample the resistance value (R=V / I). The control module is controlled through the host computer communication interface to switch the resistance temperature module settings to generate different resistance values. The temperature value sampled by the electromagnetic flowmeter is then read through the communication module (the temperature is calculated from the resistance temperature according to the resistance temperature calibration table), thereby detecting whether the resistance temperature function of the electromagnetic flowmeter is normal.

[0035] Step S2.3.4: Pulse detection; The electromagnetic flowmeter outputs a pulse signal to the pulse detection module of the calibration fixture through the pin of the calibration fixture base. The pulse size is determined by the flow signal size. The flow signal module level is controlled by the host computer communication interface. By comparing the number of pulses measured by the pulse detection module with the theoretical number of pulses, the abnormality of the electromagnetic flowmeter's pulse function can be detected.

[0036] Step S2.3.5: Switch quantity detection; The control module is controlled through the upper communication interface to output high and low levels, and the output is sent to the electromagnetic flowmeter through the pin of the calibration fixture base. Then, the switch quantity status in the electromagnetic flowmeter is read through the communication module to see if the high and low levels correspond.

[0037] Step S2.3.6: Alarm detection; The upper computer communication module controls the relay switch of the electromagnetic flowmeter to switch on or off, and then the alarm detection module detects the level of the IO port to determine whether the alarm function of the electromagnetic flowmeter is normal.

[0038] Step S2.3.7: Output detection; The current value of the electromagnetic flowmeter 4-20mA output is controlled through the host computer communication interface. The 4-20mA current signal is connected to the 4-20mA detection module through the pin of the calibration fixture base. The current value is measured by the 4-20mA detection module. The theoretical value is compared with the actual measured value to determine whether the 4-20mA output function of the electromagnetic flowmeter is normal.

[0039] Step S2.3.8: HART detection; Based on the host computer communication interface, HART general commands are sent through the HART module, and the response of the electromagnetic flowmeter is obtained through the HART module. The HART function of the electromagnetic flowmeter is detected by judging the format and content of the response message (the connection cable of the HART module is shared with the 4-20mA connection cable).

[0040] Step S2.3.9: Clock detection; Based on the host computer communication interface, the time of the host computer is obtained and transmitted to the electromagnetic flowmeter through the communication module.

[0041] The advantages and beneficial effects of this invention are as follows:

[0042] This invention integrates the excitation current, flow signal, communication, output, and thermal resistance calibration of the electromagnetic flowmeter converter into a calibration and testing fixture, which is automatically controlled by software. This ensures that the performance indicators of each electromagnetic converter are consistent, reduces quality accidents caused by human factors, and improves production efficiency. By recording the calibration and testing data of each electromagnetic flowmeter converter produced and automatically uploading them to the server, permanent traceability and fault finding and analysis can be facilitated. Attached Figure Description

[0043] Figure 1 This is a front structural diagram of the calibration fixture in an embodiment of the present invention.

[0044] Figure 2 This is a side perspective view of the calibration fixture in an embodiment of the present invention.

[0045] Figure 3 This is a front perspective view of the calibration fixture in an embodiment of the present invention.

[0046] Figure 4 This is a schematic diagram of the back structure of the calibration fixture in an embodiment of the present invention.

[0047] Figure 5 This is a top view of the calibration fixture in an embodiment of the present invention.

[0048] Figure 6 This is a schematic diagram of the calibration fixture for installing the movement in an embodiment of the present invention.

[0049] Figure 7 This is a schematic diagram of the system structure in an embodiment of the present invention.

[0050] Figure 8 This is a flowchart of the method in an embodiment of the present invention. Detailed Implementation

[0051] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0052] like Figures 1 to 6As shown, an automated calibration fixture for an electromagnetic flowmeter converter reduces the probability of errors caused by manual intervention through mechanical fixtures, while improving efficiency and increasing the possibility of mass production. The fixture includes a main body box 2 and a clamping mechanism. The upper part of the main body box 2 is provided with a recessed base, and the base pin 5 is provided on the base. A power switch 1 is provided on one side of the main body box 2, and a cable outlet 10 and a power socket 11 are provided on the other side. The clamping mechanism includes a baffle 6, a slide bar 7, a longitudinal limiting block 8, a push plate 9, a push rod assembly 3, and a transverse limiting block 12. The push plate 9 is provided with excitation and signal pin blocks 4, and the baffle 6 and the push plate 9 are respectively provided with corresponding transverse limiting blocks 12. Limiting blocks 12, baffles 6 and push plates 9 are respectively disposed on the left and right sides of the base, longitudinal limiting blocks 8 are respectively disposed on the front and rear sides of the base, push plates 9 are respectively connected to slide rods 7 and push rod assemblies 3, and push plates 9 are laterally slid along slide rods 7 relative to baffles 6 by pulling push rod assemblies 3, the base pin 5 is configured to cooperate with the bottom of the core 13 of the electromagnetic flowmeter converter so that the core 13 can be quickly fixed to the base pin 5, the excitation and signal pin block 4 is configured to cooperate with the terminal on one side of the core 13, and the longitudinal limiting blocks 8 and lateral limiting blocks 12 are configured to cooperate with the outer periphery of the core 13 to fix the position of the core 13.

[0053] like Figure 7 As shown, an automated calibration system for an electromagnetic flowmeter converter includes a calibration fixture and a calibration unit. The calibration unit includes a control module and, respectively, a power supply module, an excitation current detection module, a flow signal module, a communication module, a thermal resistance module, a clock, a HART communication module, a 4-20mA detection module, a pulse detection module, a switch alarm output detection module, and a host computer communication interface, all connected to the control module. The base pin 5 of the calibration fixture is connected to both the control module and the power supply module. The excitation and signal pin blocks 4 are connected to the flow signal module. The excitation pin is connected to the excitation current input terminal of the flow signal module via a wire, and the signal pin is connected to the flow signal output terminal of the flow signal module. The excitation current detection module is connected to the flow signal module and is used to detect the magnitude of the input excitation current.

[0054] The power module is powered by a DC-005 power adapter (5V) or a USB data cable.

[0055] The excitation current detection module uses a precision operational amplifier and an MCU built-in ADC for sampling to detect the magnitude and frequency of the excitation current of the electromagnetic flowmeter; the current calculation algorithm is: I=V / R.

[0056] The flow signal module uses a resistor network to simulate the electromagnetic sensor and fluid medium used in a real electromagnetic flow meter. Different resistance ratios represent the flow rate of the fluid in the pipe. Only an excitation current needs to be input to obtain the flow signal, which simplifies the cost. Moreover, because it is built using resistors, the flow signal module is very stable and will not produce errors like electromagnetic sensors and fluids in actual use.

[0057] The communication module uses an RS485 communication circuit to communicate with the electromagnetic flowmeter;

[0058] The RTD module (PT1000) uses a precision resistor and has a four-wire output to facilitate the RTD function calibration and testing of the electromagnetic flow converter.

[0059] The HART communication module enables HART communication with the electromagnetic flowmeter.

[0060] The 4-20mA detection module uses a high-precision, low-temperature drift precision resistor as the sampling resistor, and acquires and converts 4-20mA through a 24-bit ADC of an analog chip, with a sampling resolution of up to 1uA.

[0061] The pulse detection module uses the MCU's internal timer to count pulses / frequency.

[0062] The switch alarm output detection module uses the MCU's general-purpose I / O port to detect high and low levels.

[0063] The host computer communication interface uses the MCU's built-in full-speed USB interface to communicate with the PC software, enabling software control of all tooling functions; all calibration and test results are uploaded to the server, facilitating subsequent maintenance of the electromagnetic flowmeter and monitoring of its production quality.

[0064] like Figure 8 As shown, an automated calibration method for an electromagnetic flowmeter converter includes the following steps:

[0065] Step S1: Electromagnetic flowmeter converter installation. The electromagnetic flowmeter converter is installed on the calibration fixture, specifically including the following steps:

[0066] Step S1.1: Pull the push rod 3 to the right so that the bottom of the core 13 of the electromagnetic flowmeter converter is connected to the base through the base pin 5, and connected to the control board and power cord through the base pin 5, so as to realize the quick connection of the electromagnetic converter core 13 without manual wiring and reduce wiring failures.

[0067] Step S1.2: Push the push rod 3 to the left so that the excitation and signal pin block 4 on the push plate 9 is connected to the excitation and signal terminals of the mechanism 13. At the same time, the mechanism 13 is limited in the horizontal direction by the longitudinal limiting block 8 and the transverse limiting block 12. In fact, the base pin 5 at the bottom of the mechanism 13 and the excitation and signal pin block 4 on the side also provide horizontal and vertical limits to a certain extent.

[0068] After the movement 13 is fixed, connect a power source (220VAC or 24VDC) to the power socket, and then turn on the power switch 1. The entire connection process is now complete.

[0069] Step S2: Electromagnetic flowmeter converter calibration; By clicking on the electromagnetic flowmeter converter automated calibration system, perform automated calibration of various functions of the electromagnetic flowmeter converter core 13, specifically including the following steps:

[0070] Step S2.1: Open the host computer software, click Start to enter automatic calibration. The host computer software reads the electromagnetic flowmeter converter information (such as model) through the host computer communication interface via communication commands.

[0071] Step S2.2: Based on the electromagnetic flowmeter converter information, automatically perform converter excitation, signal, and output function calibration;

[0072] The electromagnetic flowmeter outputs excitation current to the flow signal module of the fixture through the excitation pin. The signal pin then obtains flow data (voltage value) from the flow signal module. The fixture issues calibration commands through the communication module. The electromagnetic flowmeter continuously obtains flow data within a certain period of time and calculates the average value. This average value is used as the standard flow data, and the calibration coefficient (related to the hardware of each electromagnetic flowmeter) is calculated. After all electromagnetic flowmeters are calibrated by the same fixture or a fixture of the same series that meets the accuracy requirements, the errors between hardware are eliminated, and the calibration is completed.

[0073] The core formula of an electromagnetic flowmeter:

[0074] E=KBdv

[0075] Where E represents the signal voltage between the electrodes, K represents the normalization coefficient of the converter (i.e., a coefficient related to the magnetic field distribution and the axial length of the sensor), B represents the magnetic flux density, d represents the inner diameter of the measuring tube, and v represents the average flow velocity. Since the excitation current is constant, B is a constant.

[0076] Step S2.3: After calibration, the calibration system automatically tests various functions of the electromagnetic flowmeter converter and determines the various indicators of the electromagnetic converter based on the test results; the test process is as follows:

[0077] Step S2.3.1: The tooling obtains the excitation current (current) through the excitation pin and enters the flow signal module. After the excitation current flows into the flow signal module, it generates a flow signal (voltage) on the signal pin and outputs it to the electromagnetic flow meter. The host computer software can control the control module through the USB interface to switch the speed of the flow signal module. The resulting flow signal (voltage) will be different. The host computer software then reads the flow rate of the electromagnetic flow meter through the communication module to detect whether the flow function of the electromagnetic flow meter is normal.

[0078] Step S2.3.2: Excitation current detection: The fixture measures the excitation current value output from the electromagnetic flowmeter to the flow signal module through the excitation current detection module, and compares it with the theoretical excitation current (determined by hardware and input before calibration test).

[0079] Step S2.3.3: Resistance Temperature Detection: The electromagnetic flowmeter outputs a current signal to the resistance temperature module of the fixture through the pin of the calibration fixture base, and then obtains a voltage signal through the pin to sample the resistance value (R=V / I). The host computer software controls the control module through the USB interface, which can switch the resistance temperature module settings to generate different resistance values. Then, the temperature value sampled by the electromagnetic flowmeter is read through the communication module (the temperature is calculated from the resistance temperature according to the resistance temperature calibration table), thereby detecting whether the resistance temperature function of the electromagnetic flowmeter is normal.

[0080] Step S2.3.4: Pulse Detection: The electromagnetic flowmeter outputs a pulse signal to the pulse detection module of the fixture via the pin on the calibration fixture base. The pulse magnitude is determined by the flow signal magnitude, i.e., by the speed control of the flow signal module by the host computer software. The host computer software compares the number of pulses measured by the pulse detection module with the theoretical number of pulses to detect whether the pulse function of the electromagnetic flowmeter is abnormal.

[0081] Step S2.3.5: Switch quantity detection: The host computer software outputs high and low levels through the IO port of the control module (MCU), and outputs them to the electromagnetic flowmeter through the pin of the calibration fixture base. Then, the communication module reads whether the switch quantity status in the electromagnetic flowmeter corresponds to the high and low levels.

[0082] Step S2.3.6: Alarm detection: The host computer software controls the relay switch or closure of the electromagnetic flowmeter through the communication module, and then detects the level of the IO port through the alarm detection module to determine whether the alarm function of the electromagnetic flowmeter is normal.

[0083] Step S2.3.7: Output detection: The host computer software controls the current value of the electromagnetic flowmeter 4-20mA output through the communication module. The 4-20mA current signal is connected to the 4-20mA detection module through the pin of the calibration fixture base. The current value is measured by the 4-20mA detection module. The theoretical value is compared with the actual measured value to determine whether the electromagnetic flowmeter 4-20mA output function is normal.

[0084] Step S2.3.8: HART detection: The host computer software sends HART general commands through the HART module, and then obtains the response from the electromagnetic flowmeter through the HART module. The HART function of the electromagnetic flowmeter is checked by judging the format and content of the response message (the connection cable of the HART module is shared with the 4-20mA connection cable).

[0085] Step S2.3.9: Clock detection: The clock function only performs calibration. The host computer software obtains the time from the local computer and transmits it to the electromagnetic flowmeter through the communication module to complete the time calibration.

[0086] Step S2.4: The calibration results and test data are automatically uploaded to a local or remote server and can be queried by logging in through the host computer software.

[0087] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. An electromagnetic flowmeter transducer automated calibration fixture, comprising a main body tank (2) and a clamping mechanism, characterized in that: The main box (2) upper portion is provided with a recessed base, the base is provided with a base thimble (5), the clamping mechanism includes baffles (6) and push plates (9) respectively arranged on both sides of the base, the push plate (9) adjusts the distance between the push plate (9) and the baffle (6) through the slide rod (7), and the push plate (9) is provided with an excitation and signal thimble block (4) on the side of the base; the base thimble (5) is matched with the bottom of the movement (13) of the electromagnetic flowmeter converter, and the excitation and signal thimble block thimble block (4) is matched with the terminal on one side of the movement (13).

2. An electromagnetic flowmeter transducer automated calibration fixture according to claim 1, wherein: The baffles (6) and push plates (9) arranged on the left and right sides of the base are respectively provided with corresponding transverse limiting blocks (12), and the front and rear sides of the base are respectively provided with longitudinal limiting blocks (8), and the longitudinal limiting blocks (8) and the transverse limiting blocks (12) are matched with the outer periphery of the movement (13).

3. An electromagnetic flowmeter transducer automated calibration fixture according to claim 1, wherein: The push plate (9) is provided with a push rod assembly (3) on the other side of the base, and the push plate (9) slides along the slide rod (7) relative to the baffle (6) by pulling the push rod assembly (3).

4. An electromagnetic flowmeter transducer automated calibration system comprising a calibration fixture and a calibration unit, characterized by: The calibration tool adopts the electromagnetic flowmeter converter automatic calibration tool of claim 1, and the calibration unit includes a control module, a power module, an excitation current detection module, a flow signal module, a communication module and a host computer communication interface connected with the control module; the base thimble (5) of the calibration tool is connected with the control module and the power module, the excitation and signal thimble block (4) is connected with the flow signal module, so that the excitation thimble of the excitation and signal thimble block (4) is connected to the excitation current input terminal of the flow signal module, the signal thimble of the excitation and signal thimble block (4) is connected to the flow signal output terminal of the flow signal module, the excitation current detection module is connected with the flow signal module and is used for detecting the input excitation current, the communication module acquires electromagnetic flowmeter data, and the host computer communication interface uploads the calibration result and the detection data to the host computer.

5. An electromagnetic flowmeter transducer automated calibration system according to claim 4, wherein: The excitation current detection module is provided with an ADC sampling function, which is used for detecting the size of the electromagnetic flowmeter excitation current simulated by the flow signal module and the excitation frequency.

6. An electromagnetic flowmeter transducer automated calibration system according to claim 4, wherein: The flow signal module uses a resistance network to simulate a real electromagnetic flowmeter, and different resistance ratios represent the size of the fluid flow in the pipeline, and the flow signal is obtained by acquiring the excitation current.

7. An electromagnetic flowmeter transducer automated calibration system according to claim 4, wherein: The control module is further connected with a thermistor module, a clock, a HART communication module, a detection module, a pulse detection module and a switching value alarm output detection module. The thermistor module adopts a precision resistor and four-wire output to calibrate and detect the thermistor function of the electromagnetic flow converter. The HART communication module is used to realize the HART communication function with the electromagnetic flowmeter. The detection module uses a precision resistor as a sampling resistor and an analog chip ADC to collect and convert. The pulse detection module uses the internal timer of the control module to count the pulse / frequency. The switching value alarm output detection module uses the general IO port of the control module to detect the high and low levels.

8. An electromagnetic flowmeter transducer automated calibration method characterized by: The application discloses an automatic calibration system for electromagnetic flowmeter converters, and relates to the technical field of electromagnetic flowmeter calibration. S1: installing the electromagnetic flowmeter converter on the calibration tool; S2: calibrating the electromagnetic flowmeter converter through the automatic calibration system; S2.1: reading the electromagnetic flowmeter converter information through the host computer communication interface; The electromagnetic flowmeter outputs excitation current to the flow signal module through the excitation probe, obtains flow data from the flow signal module through the signal probe, and sends a calibration command through the communication module; the electromagnetic flowmeter continuously obtains flow data within a certain time, calculates an average value as standard flow data, and calculates a calibration coefficient related to the hardware of each electromagnetic flowmeter; all the electromagnetic flowmeters are calibrated through the same calibration tool or the same series of calibration tools meeting the precision requirement; S2.3: after the calibration, the automatic calibration system detects various functions of the electromagnetic flowmeter converter and determines the indexes of the electromagnetic flowmeter converter according to the detection results; S2.4: the calibration results and the detection data are uploaded through the host computer communication interface. S1.1: pulling the push rod (3) to the right to connect the bottom of the movement (13) of the electromagnetic flowmeter converter with the base through the base probe (5); The control module is further connected with a thermal resistance module, a clock, a HART communication module, a detection module, a pulse detection module and a switching value alarm output detection module; the detection in S2.3 includes the following steps:

9. An automated electromagnetic flowmeter converter calibration method as defined in claim 8, wherein: S2.3.1: the calibration tool obtains excitation current through the excitation probe, and the excitation current enters the flow signal module; after the excitation current flows into the flow signal module, a flow signal is generated on the signal probe and output to the electromagnetic flowmeter; the host computer communication interface can be used to control the control module to switch the gear of the flow signal module to generate different flow signals, and the communication module is used to read the flow size of the electromagnetic flowmeter to detect whether the flow function of the electromagnetic flowmeter is normal; S2.3.2: excitation current detection; the calibration tool measures the excitation current value output by the electromagnetic flowmeter to the flow signal module through the excitation current detection module, and compares the excitation current value with a theoretical excitation current value. ​ 10. The method of claim 8, wherein: ​ ​ ​ Step S2.3.3: thermal resistance detection; the electromagnetic flowmeter outputs a current signal to the thermal resistance module of the calibration tool through the stylus of the calibration tool base, and acquires a voltage signal through the stylus to sample a resistance value, the control module is controlled through the host computer communication interface, the gear position of the thermal resistance module is switched to generate different resistance values, and the temperature value sampled by the electromagnetic flowmeter is read through the communication module, so that whether the thermal resistance function of the electromagnetic flowmeter is normal is detected; Step S2.3.4: pulse detection; the electromagnetic flowmeter outputs a pulse signal to the pulse detection module of the calibration tool through the stylus of the calibration tool base, the pulse size is determined by the flow signal size, the gear position of the flow signal module is controlled through the host computer communication interface, and whether the pulse function of the electromagnetic flowmeter is abnormal is detected by comparing the number of pulses measured by the pulse detection module with the number of theoretical pulses; Step S2.3.5: switch value detection; the control module is controlled through the host computer communication interface, a high level and a low level are output, and the high level and the low level are output to the electromagnetic flowmeter through the stylus of the calibration tool base, and whether the switch value state in the electromagnetic flowmeter corresponds to the high level and the low level is read through the communication module; Step S2.3.6: alarm detection; the relay switch or closure of the electromagnetic flowmeter is controlled through the host computer communication module, and the level of the IO port is detected through the alarm detection module to determine whether the alarm function of the electromagnetic flowmeter is normal; Step S2.3.7: output detection; the current value output by the electromagnetic flowmeter is controlled through the host computer communication interface, the current signal is connected to the detection module through the stylus of the calibration tool base, the current value is measured through the detection module, the theoretical value is compared with the actual measured value, and whether the output function of the electromagnetic flowmeter is normal is determined; Step S2.3.8: HART detection; the HART module is used to issue a HART general command based on the host computer communication interface, the response of the electromagnetic flowmeter is acquired through the HART module, and whether the HART function of the electromagnetic flowmeter is normal is detected by judging the format and content of the response message; Step S2.3.9: clock detection; the local time of the host computer is acquired based on the host computer communication interface, and is transmitted to the electromagnetic flowmeter through the communication module.

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