Sand and dust test chamber calibration device and method of use

Abstract

The application belongs to the technical field of sand dust test equipment, and particularly relates to a sand dust test box calibration device and a use method thereof, which comprises: a sealed main machine box; a power supply module, a core control module, an air path and sampling control module, a man-machine interaction module and a wireless communication module integrated in the main machine box; the air path and sampling control module comprises an air suction pump, a gas mass flow meter and a busbar with at least two independent sampling channels connected in sequence, and an electromagnetic valve controlled by the core control module is arranged on each sampling channel; the wireless communication module is used for receiving control instructions sent by a remote wireless remote controller; and the man-machine interaction module is used for parameter setting, information input and state display. The application is highly integrated and portable, integrates power, metering, control and interaction systems in a sealed box body, greatly simplifies the equipment structure of field calibration, is convenient to carry and arrange, and is particularly suitable for field calibration operation.

Description

Technical Field

[0001] This invention relates to the technical field of sand and dust testing equipment, specifically to a sand and dust testing chamber calibration device and its usage method. Background Technology

[0002] A dust test chamber is an important environmental testing device used to simulate natural dust environments and evaluate the dustproof sealing performance and operational reliability of products (such as electronic components, aerospace equipment, and automotive parts). Its core performance indicators, including the spatial uniformity of dust mass concentration within the chamber, its stability over time, and the dust settling rate, directly determine the severity and reproducibility of the test conditions, and are the cornerstone of ensuring the validity, comparability, and authority of the test results. Therefore, regular calibration of the dust test chamber is a necessary means to ensure that its performance meets the requirements of national military standards (such as GJB150.12A), national military standards (such as GJB360B), and other relevant industry specifications.

[0003] Currently, the calibration of this type of equipment mainly relies on traditional, non-integrated equipment combinations and manual operation methods, which typically include the following independent steps: First, using an independent vacuum pump or sampling pump, the sampling flow rate is manually controlled and measured using a rotor flow meter or orifice flow meter combined with a stopwatch; second, multiple dust samplers (such as filter membrane clips with filter membranes) are manually placed in different positions inside the test chamber, and the sampling points are switched by using a three-way valve or manually inserting and removing the tubing; after sampling, the samplers are removed, and the mass before and after sampling is weighed using a high-precision electronic balance; finally, the dust concentration at each point is obtained by manually calculating the sampling volume (flow rate × time) and the dust mass increment.

[0004] The aforementioned traditional calibration methods have several significant technical bottlenecks and inherent defects:

[0005] The equipment is scattered and the operation is cumbersome: the air pumps, flow meters, timers, samplers, balances and other equipment required for calibration are independent of each other, inconvenient to carry, time-consuming and labor-intensive to set up on site, and the calibration process has many steps, which requires high technical proficiency from the operators and results in low overall efficiency.

[0006] Insufficient flow control accuracy and stability: The instruments used, such as rotor flowmeters, have relatively low accuracy and are easily affected by changes in ambient temperature, pressure, and pipeline resistance, making it difficult to achieve high-precision flow setting and long-term stable control. This directly introduces flow measurement errors and affects the accuracy of the final concentration results.

[0007] Multi-point sampling is difficult to implement and suffers from poor spatial representativeness: manually switching sampling points is not only inconvenient to operate, but also makes it difficult to accurately control the start and end times of sampling at each point, making it impossible to achieve truly synchronous or precisely time-sequential multi-point sampling. This results in low efficiency in assessing the uniformity of concentration within the test chamber and weak data comparability.

[0008] It causes serious interference to the test environment: Throughout the calibration process, operators need to open the test chamber door multiple times to start the sampling pump, switch sampling points, or retrieve the sampler. This opening operation will severely disrupt the stable airflow and concentration fields established inside the chamber, causing the actual environmental parameters during sampling to deviate from the set values, making the collected samples unrepresentative and greatly reducing the reliability of the calibration results.

[0009] Low level of automation and intelligence: From flow regulation and sampling timing control to data recording, it relies heavily on manual intervention, making it difficult to achieve standardized and procedural work processes. This not only increases the risk of human error but also hinders the standardization and traceability of calibration work.

[0010] In summary, existing dust test chamber calibration technologies suffer from long-standing drawbacks such as low integration, low accuracy and efficiency, and susceptibility to interference with the operating conditions of the tested equipment. With the continuous improvement of requirements for high-end equipment manufacturing and product quality control, developing an integrated device and corresponding efficient method capable of in-situ, automatic, multi-point, and high-precision calibration has become a critical technological need urgently requiring breakthroughs in this field. Summary of the Invention

[0011] In order to overcome the above-mentioned defects in the prior art, the present invention provides a dust test chamber calibration device and its usage method.

[0012] A dust test chamber calibration device, comprising:

[0013] Sealed main unit chassis;

[0014] The power supply module, core control module, gas path and sampling control module, human-machine interaction module and wireless communication module are integrated into the main unit chassis;

[0015] The gas path and sampling control module includes an intake pump, a gas mass flow meter, and a manifold with at least two independent sampling channels connected in sequence. Each sampling channel is equipped with a solenoid valve controlled by the core control module.

[0016] The wireless communication module is used to receive control commands issued by a remote wireless remote controller;

[0017] The human-computer interaction module is used for parameter setting, information input, and status display.

[0018] Furthermore, the core control module is a programmable logic controller or a microprocessor, and the device has a continuous working mode and a jog working mode selectable through the human-machine interaction module.

[0019] Furthermore, the continuous working mode refers to the fact that after the sampling is triggered, the selected multiple sampling channels automatically complete sampling in sequence according to a preset order and sampling time; the jog working mode refers to the fact that each time an external trigger signal is received, a selected sampling channel is started to complete sampling, and then waits for the next trigger signal.

[0020] Furthermore, the wireless remote control is provided with at least a first button and a second button. The first button is used to send a command to control the start and stop of the suction pump, and the second button is used to send a command to trigger sampling start or channel switching.

[0021] The measurement signal from the gas mass flow meter is fed back to the core control module, forming a closed-loop flow control system. The device has a built-in flow calibration program that can automatically calibrate the measurement coefficient of the gas mass flow meter based on the standard flow value input after connecting an external standard flow meter.

[0022] Furthermore, the device has multiple sampling channels and a built-in air path self-test program that can automatically detect the unobstructed status of each sampling channel.

[0023] The present invention also provides a method for using a sand and dust test chamber calibration device, comprising the following steps:

[0024] Setup and connection steps: Place the main unit of the calibration device inside the dust test chamber, arrange multiple pre-weighed dust samplers at preset points inside the chamber, and connect them to the selected sampling channels of the device through pipelines;

[0025] Parameter setting steps: Set the sampling parameters through the human-computer interaction module, including target sampling flow rate, sampling volume, working mode and selected sampling channel;

[0026] Remote start-up steps: After closing the sand and dust test chamber door and establishing a stable sand and dust environment, remotely start the air pump of the device from outside the chamber using the wireless remote control to stabilize the sampling flow rate to the set value;

[0027] Automatic sampling steps: The sampling start command is triggered by the wireless remote control outside the box. The core control module automatically controls the solenoid valves of each selected sampling channel according to the set mode to complete the sand and dust collection at each point in sequence.

[0028] Data processing steps: After sampling, the dust sampler is removed and weighed again. Combined with the sampling volume data recorded by the device, the dust concentration at each sampling point is calculated.

[0029] Furthermore, in the parameter setting step, if the continuous working mode is selected and a delayed start time is set, then after the air pump starts and the flow rate stabilizes in the remote start step, the device automatically enters a delayed countdown and automatically starts sampling after the countdown ends.

[0030] Furthermore, before or periodically performing the parameter setting step, a flow rate field calibration step is also included:

[0031] Connect the exhaust port of the calibration device to a standard flow meter;

[0032] The flow calibration interface is accessed through the human-computer interaction module, and the zero point and at least one working flow point are calibrated in sequence. By inputting the measured value of the standard flow meter, the calibration of the internal flow metering system of the device is completed.

[0033] Furthermore, after the parameter setting step and before the remote start step, the device's gas path self-test program is initiated to confirm that all selected sampling channels are connected normally.

[0034] Due to the adoption of the above technical solutions, the beneficial technical effects of the present invention are as follows:

[0035] 1. This invention is highly integrated and portable, integrating power, measurement, control and interaction systems into a sealed enclosure, which greatly simplifies the equipment configuration for on-site calibration, making it easy to carry and set up, and is especially suitable for on-site calibration operations.

[0036] 2. This invention has a high level of automation and intelligence. It adopts PLC control and integrates a variety of intelligent functions such as automatic current stabilization, multi-point programmed sampling, timing, delay, self-testing, and calibration. It is easy to operate and greatly reduces the complexity and error rate of manual operation.

[0037] 3. This invention significantly improves calibration efficiency and accuracy, supports independent control of up to nine channels, and enables rapid, sequential sampling from multiple points within the test chamber, comprehensively and efficiently evaluating the uniformity of the chamber space. The high-precision mass flow meter, combined with on-site calibration, ensures the accuracy of the flow data source. Wireless remote control enables completely off-site operation, minimizing interference with the stable internal environment of the test chamber and guaranteeing the representativeness of the sampling process.

[0038] 4. The present invention features a user-friendly human-computer interaction and visible status: the large touch screen combined with multi-color status indicator lights makes parameter settings, process control, real-time status and result feedback clear at a glance.

[0039] 5. The method of this invention is standardized and normalized, providing a complete set of standard operating procedures based on intelligent devices. It transforms the calibration process from decentralized manual operation to integrated automatic control, improving the consistency and reliability of calibration results and strongly supporting the calibration requirements of military and civilian standards such as GJB150.12A and GJB360B. Attached Figure Description

[0040] Figure 1 This is a schematic diagram of the structure of a dust test chamber calibration device according to the present invention;

[0041] Figure 2 This is a schematic diagram of the internal structure of the main unit chassis of the present invention;

[0042] Figure 3 This is the usage status of the dust test chamber calibration device in this invention;

[0043] Figure 4 This is a schematic diagram of the electrical control principle of the dust test chamber calibration device in this invention.

[0044] In the diagram: 1. Main unit chassis; 2. Display controller; 3. Power socket; 4. Power switch; 5. Fuse; 6. Motor drive board; 7. Remote control receiver board; 8. Power board; 9. Lithium battery; 10. Busbar; 11. Intake pump; 12. Gas mass flow meter; 13. Piping; 14. Solenoid valve; 15. Exhaust port; 16. Green indicator light; 17. Air inlet; 18. Blue air pump working indicator light; 19. Red system status indicator light; 20. Dust test chamber; 21. Support rod; 22. Sampling filter; 23. Silicone tubing. Detailed Implementation

[0045] To more clearly illustrate the technical solution of the present invention, the present invention will be further described below with reference to the accompanying drawings. Obviously, the drawings described below are only one embodiment of the present invention. For those skilled in the art, other embodiments can be obtained based on these drawings and embodiments without creative effort, and all of them fall within the protection scope of the present invention.

[0046] Example 1: This example describes in detail the structure and function of the calibration device. For example... Figure 1-2 As shown, the calibration device mainly includes the following parts:

[0047] Main Unit Housing and Protection System: The main unit housing 1 is made of high-strength materials with sealing strips at the seams, achieving an IP54 level of dust and water resistance, ensuring its ability to operate directly in the harsh environment of a sand and dust test chamber. The front of the housing features a display controller 2, a power switch 4 below it, a power socket 3, and a fuse 5. The sides of the housing include an air inlet 17, an exhaust outlet 15, and air path interfaces for nine sampling channels. All interfaces are sealed with caps when not in use.

[0048] Internal Electrical and Control System: Upon opening the main unit chassis, the internal layout is compact. The bottom layer is the power supply board 8, responsible for converting, distributing, and managing the built-in 24V / 3000mAh lithium battery 9 or external input power, and supplying power to all modules. The middle layer is the core control area, including the motor drive board 6 and the main controller (not shown separately in the diagram, but integrated into the board) based on a PLC (Programmable Logic Controller). The PLC receives instructions from the touchscreen and remote control receiver board 7 and issues control signals. The top layer is the pneumatic execution area.

[0049] High-precision gas path and sampling system: This is the core metering unit of this device. The suction pump 11 serves as the power source, and its inlet is connected to the air inlet 17 via pipe 13. The outlet of the suction pump 11 is directly connected to the inlet of a high-precision gas mass flow meter 12. This gas mass flow meter 12 uses a thermal principle, with a range of (0.5~5.0) L / min and an accuracy of ±(1.5% reading + 0.2% full scale). Its output signal (4-20mA or digital signal) is fed back to the PLC in real time. The outlet of the gas mass flow meter is connected to a nine-channel manifold 10. Each outlet branch of the manifold 10 has a normally closed two-position two-way solenoid valve 14 connected in series. The coils of the nine solenoid valves 14 are controlled by the drive circuit on the motor drive board 6, and the on / off commands come from the PLC. The outlet of each solenoid valve 14 corresponds to an external sampling gas path interface. On the front of the main unit 1, a green indicator light 16 is provided for each sampling channel. When a solenoid valve 14 in a certain channel is open, its corresponding indicator light remains constantly lit. In addition, the main unit 1 is equipped with a blue air pump operation indicator and a red system status indicator to indicate the status of air pump operation and flow stability.

[0050] Wireless remote control system: The remote control receiver board 7 receives signals from an independent wireless remote control (using the 433MHz or 2.4GHz frequency band). The remote control panel is simple, with two buttons, "A" and "B". Pressing the "A" button sends a start / stop command for the air pump, and pressing and holding the "A" button for 3 seconds sends a system reset command; pressing the "B" button sends a sampling trigger command. All commands are parsed and executed by the PLC, enabling complete remote control by the operator outside the sand and dust test chamber.

[0051] Intelligent control software system: The software is embedded in the PLC and touch screen. Its main functions include:

[0052] Parameter settings: Users can set the target sampling flow rate (e.g., 1.0 L / min), sampling volume (e.g., 1L), sampling time (automatic calculation or manual input), and delay start time (0-9999 seconds) via the touch screen, and can select 1 to 9 sampling channels that need to work.

[0053] Operating modes: Two modes are available: "Continuous" and "Jog". In "Continuous" mode, after one trigger (B key or delay end), the PLC automatically controls the solenoid valves of each selected channel to open and close sequentially according to the channel number. In "Jog" mode, each press of the B key controls the PLC to operate the next selected channel.

[0054] Flow closed-loop control: The PLC compares the real-time flow value fed back by the flow meter with the set value, and dynamically adjusts the drive voltage of the suction pump (through the motor drive board 6) through the PID algorithm to achieve rapid flow stabilization. The stabilization time is usually less than 2 minutes.

[0055] Self-test function: After startup, the PLC can quickly open and close each solenoid valve in sequence. By monitoring the change in the flow meter reading in a very short time, it can determine whether the air path of each channel is unobstructed and display the result on the screen with "√" or "×".

[0056] On-site calibration function: Enter the calibration interface (password required), connect exhaust port 15 to a standard soap film flow meter. The user inputs the "calibration flow value" (e.g., 2.0 L / min). After the device stabilizes, the user inputs the actual measured "standard flow value" of the soap film flow meter (e.g., 2.05 L / min) on the interface, clicks "calibrate," and the PLC automatically calculates and stores the new flow correction coefficient K (K = standard value / displayed value), completing the calibration at that point. Zero-point and multiple flow point calibrations are possible.

[0057] Example 2: Method for calibrating a sand and dust test chamber using the aforementioned device

[0058] This embodiment details the complete process of calibrating the concentration uniformity of a dust test chamber conforming to the GJB150.12A standard using the device described in Embodiment 1. Figure 1-4 As shown, the specific steps are as follows:

[0059] S101: Preparation and Initial Weighing. Before calibration, use a precision electronic balance (external device) with an accuracy of 0.1 mg to weigh the nine clean dust sampling filters 22 and record the initial masses m_initial1 to m_initial9. Preheat the electronic balance for 2 hours to ensure accuracy.

[0060] S102: Device Arrangement and Connection. Open the door of the dust test chamber 1 and place the calibration device main unit 5 in the center of the chamber (ensuring that airflow is not obstructed). Using the adjustable support rod 21, arrange the nine pre-weighed sampling filters 22 at nine representative positions in the test chamber: top, middle, bottom, left, right, front, and back. Use silicone tubing 23 with matching inner diameter to tightly connect the outlet of each sampling filter 22 to the corresponding sampling channel interface 1-9 on the calibration device panel, ensuring no leakage. Seal any unused interfaces on the device with caps.

[0061] S103: Parameter Setting and Device Self-Test. Operate the calibration device touchscreen outside the chamber. Set parameters: Since the specification requires one of the concentration points to be (1.1±0.3) g / m³, set the sampling flow rate to 1.0 L / min and the sampling volume to 1 L. The system automatically calculates the sampling time as 1 minute (60 seconds). Select "Continuous" as the working mode. In the channel selection interface, select all 9 channels. Set the delay start time to 180 seconds to allow sufficient time for the gas pump to stabilize the flow after triggering. After setting, click the "Self-Test" function button. The device will automatically and quickly test the gas path of the 9 channels, and the screen will display "Test passed" (green √) for all channels.

[0062] S104: Environment Setup and Remote Start-up. Close and lock the dust test chamber door. Start the dust test chamber and run it according to the standard procedure until the control panel displays that the dust concentration inside the chamber has reached and stabilized at the target value of approximately 1.1 g / m³. At this point, the operator presses the "A" button on the wireless remote control outside the chamber. The air pump 11 inside the calibration device starts, and the blue indicator light illuminates. The touchscreen displays the real-time flow rate rising from 0, and the red status indicator light flashes at 1-second intervals. After approximately 90 seconds, the flow rate stabilizes at 1.0 L / min, and the red indicator light goes out.

[0063] S105: Automatic Sampling Process. After the flow rate stabilizes, the device automatically starts a 180-second countdown. After the countdown ends (without manual intervention), the PLC automatically triggers the sampling process: First, the solenoid valve of channel 1 is opened, the green indicator light of channel 1 illuminates, and air is pumped from sampling point 1. Simultaneously, the timer on the screen starts a 60-second countdown. After 60 seconds, the PLC closes solenoid valve 14 (the indicator light goes out), then opens solenoid valve 14 of channel 2 to begin sampling at point 2, and so on. The entire process is fully automatic; the operator only needs to observe the indicator lights and the screen to confirm the progress.

[0064] S106: Post-sampling processing and data calculation. After sampling in channel 9 is complete, all green channel indicator lights will turn off, the red status indicator lights will remain on, and a "Sampling complete!" message will pop up on the screen. After the dust test chamber has completed the specified testing time and allowed to settle, open the chamber door. Carefully remove the nine samplers 3 and gently clean the surface of each sampler with a soft brush or blower to remove any remaining dust (be careful not to lose the dust collected on the filter membrane). Then, weigh them again using the same precision electronic balance and record the final mass m. 终1 to m 终9 .

[0065] S107: Concentration Calculation and Result Analysis. For the i-th sampling point (i=1-9):

[0066] Sampling dust mass Δmi = m 终i - m初i (Unit: g)

[0067] Sampling volume Vi = Set flow rate × Sampling time = 1.0 L / min × 1 min = 1 L = 0.001 m³

[0068] The dust concentration at this point is Ci = Δmi / Vi (unit: g / m³).

[0069] Calculate the concentration values ​​C1 to C9 at 9 points, and then calculate the average value C. avg Maximum value C max Minimum value C min And calculate the uniformity: 1 - {(C max - Cmin) / (2 * C avg )}× 100%. Determine whether the uniformity of the dust test chamber at this concentration point is qualified according to the calibration specifications.

[0070] S108: Device Maintenance. After calibration, turn off the device power switch. Wipe the device surface with a clean cloth to remove dust. Check the battery level and charge it if necessary. Seal all sampling gas line interfaces with caps and store the device back in its dedicated instrument case.

[0071] In addition, on-site flow calibration can be performed as a step before regular maintenance or first use: Before S103, connect the soap film flow meter to the device exhaust port 15 via a hose. On the device, enter the calibration interface and complete the calibration of the zero point (enter the standard value 0) and two commonly used flow points, 2.0 L / min and 5.0 L / min, in sequence. Enter the accurate measured value of the soap film flow meter to ensure the accuracy of the device's own measurement.

[0072] As can be seen from the above specific embodiments, the device and method provided by the present invention transform the complex multi-point dust sampling and calibration process into a highly automated standard operation, which greatly improves the efficiency, accuracy and reliability of calibration work, while minimizing interference with the internal environment of the tested equipment, and has significant practical value.

[0073] It should be noted that the device structure and accompanying drawings of this invention mainly describe the principle of this invention. In terms of the technical aspects of this design principle, the setting of the power mechanism, power supply system and control system of the device is not fully described. However, under the premise that those skilled in the art understand the principle of the above invention, the specific details of its power mechanism, power supply system and control system can be clearly understood. The control method in the application document is automatic control through a controller. The control circuit of the controller can be implemented by those skilled in the art through simple programming.

[0074] All standard parts used can be purchased from the market, and can be customized according to the instructions and drawings. The specific connection methods of each part adopt conventional methods such as bolts, rivets, and welding that are mature in the existing technology. The machinery, parts and equipment adopt conventional models in the existing technology, and the structure and principle of the components known to those skilled in the art can be known by those skilled in the art through technical manuals or conventional experimental methods.

[0075] The above embodiments are merely exemplary embodiments of the present invention and are not intended to limit the present invention. The scope of protection of the present invention is defined by the claims. Those skilled in the art can make various modifications or equivalent substitutions to the present invention within the scope of its essence and protection. Such modifications or equivalent substitutions should also be considered to fall within the scope of protection of the present invention.

Claims

1. A calibration device for a sand and dust test chamber (20), characterized in that, include: Sealed main unit chassis (1); The power supply module, core control module, gas path and sampling control module, human-machine interaction module and wireless communication module are integrated in the main unit (1); The gas path and sampling control module includes a suction pump (11), a gas mass flow meter (12), and a manifold (10) with at least two independent sampling channels connected in sequence. Each sampling channel is equipped with a solenoid valve (14) controlled by the core control module. The wireless communication module is used to receive control commands issued by a remote wireless remote controller; The human-computer interaction module is used for parameter setting, information input, and status display.

2. The dust test chamber (20) calibration device according to claim 1, characterized in that, The core control module is a programmable logic controller or a microprocessor, and has a continuous working mode and a jog working mode selectable through the human-machine interaction module.

3. The dust test chamber (20) calibration device according to claim 2, characterized in that, The continuous working mode refers to the fact that after the sampling is triggered, the selected multiple sampling channels automatically complete the sampling in sequence according to a preset order and sampling time. The jog working mode refers to the fact that each time an external trigger signal is received, a selected sampling channel is started to complete the sampling, and then waits for the next trigger signal.

4. The dust test chamber (20) calibration device according to claim 1, characterized in that, The wireless remote control is provided with at least a first button and a second button. The first button is used to send a command to control the start and stop of the suction pump (11), and the second button is used to send a command to trigger the start of sampling or channel switching.

5. The dust test chamber (20) calibration device according to claim 1, characterized in that, The measurement signal of the gas mass flow meter (12) is fed back to the core control module to form a closed-loop flow control system. The gas mass flow meter (12) has a built-in flow calibration program that can automatically calibrate the measurement coefficient of the gas mass flow meter (12) according to the standard flow value input after connecting an external standard flow meter.

6. The dust test chamber (20) calibration device according to claim 1, characterized in that, The number of sampling channels is multiple, and the main unit (1) has a built-in air circuit self-test program that can automatically detect the unobstructed status of each sampling channel.

7. A method for calibrating a dust test chamber (20) according to any one of claims 1-6, characterized in that, Includes the following steps: Arrangement and connection steps: Place the main unit (1) of the calibration device in the dust test chamber (20), arrange multiple weighed dust samplers at preset points in the chamber, and connect them to the sampling channels selected by the device through pipelines (13); Parameter setting steps: Set the sampling parameters through the human-computer interaction module, including target sampling flow rate, sampling volume, working mode and selected sampling channel; Remote start-up steps: After closing the door of the sand and dust test chamber (20) and establishing a stable sand and dust environment, remotely start the air pump (11) of the device from outside the chamber using the wireless remote control to stabilize the sampling flow rate to the set value; Automatic sampling steps: The sampling start command is triggered by a wireless remote control outside the box. The core control module automatically controls the solenoid valves (14) of each selected sampling channel according to the set mode to complete the collection of sand and dust at each point in sequence. Data processing steps: After sampling, the dust sampler is removed and weighed again. Combined with the sampling volume data recorded by the device, the dust concentration at each sampling point is calculated.

8. The method according to claim 7, characterized in that, In the parameter setting step, if the continuous working mode is selected and the delayed start time is set, the device will automatically enter the delayed countdown after the intake pump (11) starts and the flow rate stabilizes in the remote start step, and will automatically start sampling after the countdown ends.

9. The method according to claim 7, characterized in that, The process also includes a flow field calibration step, performed before or periodically before the parameter setting step. Connect the exhaust port (15) of the calibration device to a standard flow meter; The flow calibration interface is accessed through the human-computer interaction module, and the zero point and at least one working flow point are calibrated in sequence. By inputting the measured value of the standard flow meter, the calibration of the internal flow metering system of the device is completed.

10. The method according to claim 7, characterized in that, After the parameter setting step and before the remote start step, the device's gas path self-test program is initiated to confirm that all selected sampling channels are connected normally.

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