Direct-current loop resistance test system, test method and loop resistance tester

Abstract

The invention provides a direct-current loop resistance testing system and method and a loop resistance tester, and relates to the technical field of resistance testing systems.The direct-current loop resistance testing system comprises an intelligent testing module, a temperature calibration module, a data analysis module, a data comparison module, a data calibration module, a data transmission module and a data display module; and the performance and the reliability of the direct-current loop resistance test system are obviously improved. The calibration coefficient is dynamically generated and repeatedly calibrated, so that manual intervention is reduced, and the precision of measured data and the automation degree of the system are improved. The mean value and the standard deviation are calculated through the moving average method, the dynamic threshold value is generated, abnormal data can be detected and recognized more accurately, it is ensured that the system can respond to and process abnormal conditions in real time, and the real-time performance and the response speed of the system are improved. In addition, a temperature calibration method is adopted to effectively compensate the influence of temperature change on the measurement resistance, and the adaptability and robustness of the system are enhanced.

Description

Technical Field

[0001] The present invention relates to the technical field of resistance testing systems, and in particular to a direct current loop resistance testing system, a testing method and a loop resistance tester. Background Art

[0002] The basic principle of DC loop resistance test is to apply a known current to a certain loop and measure the voltage drop in the loop. By substituting the measured voltage and measured current in the loop into Ohm's law (V=IR), the resistance value of the loop can be calculated. In the current DC loop resistance test system, the traditional method usually relies on fixed thresholds and static calibration for measurement and calibration, which results in the system's adaptability and measurement accuracy being limited under different environments and working conditions. In addition, most of the existing technologies use manual calibration, which is complicated and easy to introduce human errors, and cannot respond to and handle abnormal situations in real time, reducing the automation and reliability of the system. At the same time, the effect of temperature on resistance measurement is often ignored or not handled adequately, resulting in insufficient consistency and accuracy of the measurement results under different temperature environments. In short, the existing technology has deficiencies in measurement accuracy, system automation and adaptability, and it is difficult to meet the requirements of industrial applications and scientific research for high precision and high reliability.

[0003] The above information disclosed in this Background section is only for enhancement of understanding of the background of the present disclosure and therefore it may contain information that does not constitute the prior art that is already known to one of ordinary skill in the art. Summary of the invention

[0004] The object of the present invention is to provide a DC loop resistance test system, a test method and a loop resistance tester to solve the problems raised in the above background technology.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] A DC loop resistance testing system, comprising:

[0007] An intelligent test module, which is electrically connected to the data analysis module and is used to perform a resistance test on the resistance to be tested according to preset output parameters, collect the measured voltage and measured current of the resistance to be tested during the test, and send the measured voltage and measured current to the data analysis module;

[0008] A data analysis module, which is electrically connected to the data comparison module and is used to generate an observation window that is adjusted in real time, calculate an average measurement voltage and an average measurement current based on the measurement voltage and the measurement current, perform analysis, and send the analysis result to the data comparison module;

[0009] A data comparison module, the data comparison module is electrically connected to the data calibration module, and is used to compare the analysis result with a preset dynamic threshold, generate a control signal according to the comparison result, and send the measured voltage and the measured current to the data calibration module;

[0010] A data calibration module, the data calibration module is electrically connected to the temperature calibration module and the data transmission module, and is used to substitute the measured voltage and the measured current into a preset algorithm to generate a calibration coefficient when receiving a control signal, and then adjust the abnormal average measured voltage and average measured current according to the calibration coefficient, calculate the measured resistance according to the adjusted average measured voltage and average measured current, and send the measured voltage, measured current, and measured resistance to the data transmission module;

[0011] A temperature calibration module, the temperature calibration module comprising a temperature sensing unit and a temperature calibration unit, the temperature sensing unit being electrically connected to the temperature calibration unit and being used to measure the ambient temperature of the environment in which the resistor to be measured is located, the temperature calibration unit being electrically connected to the data calibration module and being used to calibrate the measured resistor according to the ambient temperature;

[0012] A data transmission module, which is communicatively connected to the data display module and is used to send the measured voltage, measured current, and calibrated measured resistance to the data display module;

[0013] The data display module is used to visually display the measured voltage, measured current, and calibrated measured resistance.

[0014] Preferably, the calculation method for calibrating the measuring resistance is:

[0015] R c ′ =R c ×[1+a(T c -T0)]

[0016] Where R c , R c ′ They represent the measured resistance before calibration and the measured resistance after calibration respectively, a represents the preset resistance temperature coefficient, T c represents the ambient temperature, and T0 represents the preset reference temperature.

[0017] Preferably, the total number of measured voltage and measured current data collected is calibrated as K, the length of the observation window is calibrated as M, and when analyzing the measured voltage and measured current, a moving average method is used for calculation, and the calculation method is:

[0018]

[0019] In the formula represents the average measured voltage at the kth acquisition, k∈[M,K], V c (j) represents the measured voltage at the jth acquisition;

[0020] Traverse the value range of k, obtain the average measured voltage under different k values ​​and calculate the mean And the standard deviation σ is calculated as:

[0021]

[0022] The upper and lower limits of the dynamic threshold are generated based on the mean and standard deviation. The dynamic threshold is expressed as When there is When , it is considered that the average measured voltage is abnormal;

[0023] Similarly, the moving average method is used to calculate the average measured current at the kth acquisition Then calculate the mean value based on the average measured current under different k values and standard deviation σ2, and generate the corresponding dynamic threshold When there is When , the average measured current is considered abnormal.

[0024] Preferably, the length M of the observation window is generated by the total number K of measured voltage and measured current data collection, and is calculated as follows:

[0025] Preferably, the method for calibrating the abnormal measured voltage and measured current is:

[0026] Substitute the measured voltage and current in the observation window into the preset fitting error model to generate the calibration coefficient μ;

[0027] The calibration coefficient μ is used to calibrate the abnormal average measured voltage and average measured current. The calculation method is:

[0028]

[0029] In the formula Respectively represent the average measured voltage and average measured current after calibration. They represent voltage error and current error respectively, and are calculated as follows:

[0030]

[0031] In the formula represent the expected voltage and expected current respectively, where Wherein I0 represents the preset standard current, and R0 represents the preset standard resistance.

[0032] Preferably, the fitting error model is calculated using the least squares method, and the calculation method is:

[0033]

[0034] The average measurement voltage and average measurement current are repeatedly calibrated using the calibration coefficients and the average values ​​of the calibrated average measurement voltage and average measurement current are recalculated. When the calibrated average measurement voltage, average measurement current and corresponding average values ​​all meet The calibration is considered complete when

[0035] Preferably, the measuring resistance R is calculated according to the average values ​​corresponding to the average measuring voltage and the average measuring current after calibration. c ,

[0036] A DC loop resistance testing method, which is applicable to the above-mentioned testing system, comprises the following specific steps:

[0037] S1: Perform resistance test on the resistor to be tested according to the preset standard current and standard resistance set by the user, and collect the measured voltage, measured current and ambient temperature of the resistor to be tested during the test;

[0038] S2: Generate an observation window according to the total number of data collected for the measured voltage and the measured current, calculate the average measured voltage and the average measured current in the observation window, then slide the observation window to generate different average measured voltages and average measured currents, and calculate the corresponding mean and standard deviation;

[0039] S3: Substituting the average measured voltage and average measured current in different observation windows into a preset fitting error model to generate a calibration coefficient, and then generating a dynamic threshold according to the mean and standard deviation of the average measured voltage and average measured current, and comparing the average measured voltage and average measured current with the dynamic threshold to find abnormal data in the average measured voltage and average measured current;

[0040] S4: Use the calibration coefficient to calibrate the abnormal average measurement voltage and average measurement current, and calculate the corresponding measurement resistance. Then, perform temperature calibration on the measurement resistance according to the ambient temperature, generate the calibrated measurement resistance and display it visually.

[0041] A loop resistance tester is used for the above-mentioned test method.

[0042] Compared with the prior art, the present invention has the following beneficial effects:

[0043] The present invention significantly improves the performance and reliability of the DC loop resistance test system by adopting an intelligent test module, a temperature calibration module, a data analysis module, a data comparison module, a data calibration module, a data transmission module and a data display module. By dynamically generating a calibration coefficient and calibrating it repeatedly, manual intervention is reduced, and the accuracy of the measured data and the degree of automation of the system are improved. By using the moving average method to calculate the mean and standard deviation and generate a dynamic threshold, abnormal data can be detected and identified more accurately, ensuring that the system can respond and handle abnormal situations in real time, and improving the real-time performance and response speed of the system. In addition, the temperature calibration method is used to effectively compensate for the influence of temperature changes on the measured resistance, and the adaptability and robustness of the system are enhanced. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 It is a schematic diagram of the module structure of the present invention;

[0045] Figure 2 It is a schematic diagram of the overall method flow of the present invention. DETAILED DESCRIPTION

[0046] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments.

[0047] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the present invention should be understood by people with ordinary skills in the field to which the present invention belongs. The words "first", "second" and similar words used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0048] Example:

[0049] See also Figure 1 , the present invention provides a technical solution:

[0050] A DC loop resistance testing system comprises: an intelligent testing module, a temperature calibration module, a data analysis module, a data comparison module, a data calibration module, a data transmission module and a data display module.

[0051] The intelligent test module is electrically connected to the data analysis module, and a loop resistance tester of the LX3291S series may be used, which is internally provided with a high-precision current sensor and a constant current source, for performing a resistance test on the resistance to be tested according to preset output parameters, collecting the measured voltage and measured current of the resistance to be tested during the test, and sending the measured voltage and measured current together to the data analysis module.

[0052] The data analysis module is electrically connected to the data comparison module, and a Raspberry Pi 4 microprocessor equipped with a Python system can be used to generate an observation window that is adjusted in real time, and then the average measured voltage and average measured current are calculated and analyzed based on the measured voltage and measured current, and the analysis results are sent to the data comparison module.

[0053] The data comparison module is electrically connected to the data calibration module, and a Python-based computer data processing system can be used, and NumPy and Pandas libraries can be used to compare the analysis results with preset dynamic thresholds, generate control signals according to the comparison results, and send the measured voltage and measured current to the data calibration module.

[0054] The data calibration module is electrically connected to the temperature calibration module and the data transmission module, and can also use a Raspberry Pi 4 microprocessor equipped with a Python system. When receiving a control signal, the measured voltage and measured current are substituted into a preset algorithm to generate a calibration coefficient, and then the abnormal average measured voltage and average measured current are adjusted according to the calibration coefficient, and the measured resistance is calculated according to the adjusted average measured voltage and average measured current, and the measured voltage, measured current and measured resistance are sent to the data transmission module.

[0055] The temperature calibration module can adopt a DS18B20 series digital sensor, including a temperature sensing unit and a temperature calibration unit. The temperature sensing unit is electrically connected to the temperature calibration unit and is used to measure the ambient temperature of the environment in which the resistor to be measured is located. The temperature calibration unit is electrically connected to the data calibration module and is used to calibrate the measured resistor according to the ambient temperature.

[0056] The data transmission module is connected to the data display module by communication, and an ESP8266 WI FI signal module may be used to send the measured voltage, measured current, and calibrated measured resistance to the data display module.

[0057] The data display module can use an HDMI LCD display to visually display the measured voltage, measured current, and calibrated measured resistance.

[0058] By adopting the above modules, each module can perform its own function efficiently and accurately. Compared with the existing technology, the equipment and steps in the scheme have the advantages of high precision, high integration, high automation, strong flexibility, low power consumption and easy system integration. The overall scheme can significantly improve the performance and reliability of the DC loop resistance test system.

[0059] The total number of measured voltage and current data collected is calibrated as K, and the length of the observation window is calibrated as M. When analyzing the measured voltage and current, the moving average method is used for calculation. The calculation method is:

[0060]

[0061] In the formula represents the average measured voltage at the kth acquisition, that is, the average measured voltage within the observation window, k∈[M,K], V c (j) represents the measured voltage at the jth acquisition.

[0062] Traverse the value range of k, obtain the average measured voltage under different k values ​​and calculate the mean And the standard deviation σ is calculated as:

[0063]

[0064] The upper and lower limits of the dynamic threshold are generated based on the mean and standard deviation. The dynamic threshold is expressed as When there is When , it is considered that the average measured voltage is abnormal;

[0065] Similarly, the moving average method is used to calculate the average measured current at the kth acquisition Then calculate the mean value based on the average measured current under different k values and standard deviation σ2, and generate the corresponding dynamic threshold When there is When the average measured current is considered abnormal, the dynamic threshold method can more accurately reflect the normal range of the current data and reduce the probability of false positives and false negatives compared to the fixed threshold method.

[0066] The length M of the observation window is generated by the total number K of measured voltage and current data acquisitions, and is calculated as follows: The length of the observation window is proportional to the total number of data collected, that is, the more data collected, the longer the length of the observation window. This allows automatic adjustment according to real-time changes in data, thereby improving the system's adaptability to different working conditions and environments.

[0067] In this step, the moving average method is used to calculate the mean and standard deviation, and a dynamic threshold is generated, which can detect and identify abnormal data more accurately, ensuring that the system can detect and handle abnormal situations in a timely manner during the data collection process, improving the reliability and stability of the system, and the amount of calculation is small, which is more suitable for use in such small systems with limited resources. It can perform real-time calculations and analysis during the data collection process, ensuring that the system can quickly respond to and handle abnormal situations, and improving the real-time and response speed of the overall system. The dynamic threshold method can automatically adjust the threshold according to real-time data, improve the system's adaptability to different working conditions and environments, ensure that the system can accurately detect data anomalies under various conditions, and enhance the robustness of the system.

[0068] The method for calibrating abnormal measurement voltage and measurement current is as follows:

[0069] Substitute the measured voltage and current in the observation window into the preset fitting error model to generate the calibration coefficient μ;

[0070] The calibration coefficient μ is used to calibrate the abnormal average measured voltage and average measured current. The calculation method is:

[0071]

[0072] In the formula Respectively represent the average measured voltage and average measured current after calibration. They represent voltage error and current error respectively, and are calculated as follows:

[0073]

[0074] In the formula represent the expected voltage and expected current respectively, where Where I0 represents the preset standard current, and R0 represents the preset standard resistance. The preset standard current comes from the current range selected by the user, and the preset standard resistance is input by the user in advance, which represents the theoretical standard resistance value of the resistor to be measured.

[0075] The fitting error model is calculated using the least squares method, and the calculation method is:

[0076]

[0077] From the calculation formula of the calibration coefficient, it can be seen that the calibration process takes into account the difference between the actual measured data and the expected data, and can systematically correct errors to improve the accuracy of the data. The calibration coefficient is calculated based on real-time data and calibrated repeatedly until the dynamic threshold conditions are met, ensuring the reliability of the calibration results. It is suitable for different working conditions and environments, can automatically adapt to changes in measurement data, and improve the adaptability and robustness of the system.

[0078] The average measurement voltage and average measurement current are repeatedly calibrated using the calibration coefficients and the average values ​​of the calibrated average measurement voltage and average measurement current are recalculated. When the calibrated average measurement voltage, average measurement current and corresponding average values ​​all meet The calibration is considered complete when the calibration is completed. Repeat the calibration and recalculate the average measured voltage and average measured current after calibration until the data meets the dynamic threshold condition to ensure the consistency and accuracy of the data.

[0079] In this step, by adopting the above-mentioned calibration method, dynamically generating calibration coefficients and repeatedly calibrating, the accuracy of the measured data can be significantly improved, the accuracy of the measured voltage and current can be ensured, human intervention can be reduced, the degree of automation of the system can be improved, large-scale application and promotion can be facilitated, the implementation process of the system can be simplified, and the cost of system implementation can be reduced.

[0080] Calculate the measured resistance R according to the average values ​​of the average measured voltage and average measured current after calibration. c ,

[0081] The calculation method for calibrating the measured resistance is:

[0082] R c ′ =R c ×[1+a(T c -T0)]

[0083] Where R c , R c ′ They represent the measured resistance before calibration and the measured resistance after calibration respectively. a represents the preset resistance temperature coefficient. The resistance temperature coefficient is determined by the material of the resistor to be measured. Taking the common manganese copper material as an example, the resistance temperature coefficient of each batch of the resistor to be measured can be obtained from the copper strip manufacturer or the resistor manufacturer. The value range is usually 10-12ppm / ℃. c represents the ambient temperature, T0 represents the preset reference temperature, which is generally set to 22±3℃.

[0084] In this step, the calibration method can dynamically adapt to different ambient temperatures, improve the adaptability and robustness of the system, and ensure that the system can operate normally under various temperature conditions. Through the dynamic temperature calibration formula and automatic calculation process, human intervention is reduced, the degree of automation of the system is improved, and it is convenient for large-scale application and promotion.

[0085] See also Figure 2 The present invention also provides a DC loop resistance testing method, which is applicable to the above-mentioned testing system, and the specific steps include:

[0086] S1: Perform resistance test on the resistor to be tested according to the preset standard current and standard resistance set by the user, and collect the measured voltage, measured current and ambient temperature of the resistor to be tested during the test;

[0087] S2: Generate an observation window according to the total number of data collected for the measured voltage and the measured current, calculate the average measured voltage and the average measured current in the observation window, then slide the observation window to generate different average measured voltages and average measured currents, and calculate the corresponding mean and standard deviation;

[0088] S3: Substituting the average measured voltage and average measured current in different observation windows into a preset fitting error model to generate a calibration coefficient, and then generating a dynamic threshold according to the mean and standard deviation of the average measured voltage and average measured current, and comparing the average measured voltage and average measured current with the dynamic threshold to find abnormal data in the average measured voltage and average measured current;

[0089] S4: Use the calibration coefficient to calibrate the abnormal average measurement voltage and average measurement current, and calculate the corresponding measurement resistance. Then, perform temperature calibration on the measurement resistance according to the ambient temperature, generate the calibrated measurement resistance and display it visually.

[0090] The present invention also provides a loop resistance tester, which is used to execute the above-mentioned test method.

[0091] In summary, the present invention significantly improves the performance and reliability of the DC loop resistance test system by adopting an intelligent test module, a temperature calibration module, a data analysis module, a data comparison module, a data calibration module, a data transmission module and a data display module. By dynamically generating a calibration coefficient and calibrating it repeatedly, manual intervention is reduced, and the accuracy of the measured data and the degree of automation of the system are improved. By calculating the mean and standard deviation using the moving average method and generating a dynamic threshold, abnormal data can be detected and identified more accurately, ensuring that the system can respond and handle abnormal situations in real time, and improving the real-time performance and response speed of the system. In addition, the temperature calibration method is used to effectively compensate for the effect of temperature changes on the measured resistance, and the adaptability and robustness of the system are enhanced. It has significant advantages in improving measurement accuracy, degree of automation and system adaptability, and can better meet the needs of industrial applications and scientific research for high-precision and high-reliability test systems.

[0092] The above formulas are all dimensionless and numerical calculations. The formula is a formula for the most recent real situation obtained by collecting a large amount of data and performing software simulation. The preset parameters in the formula are set by technicians in this field according to actual conditions.

[0093] The above embodiments may be implemented in whole or in part by software, hardware, firmware or any other combination thereof. When implemented by software, the above embodiments may be implemented in whole or in part in the form of a computer program product. Those skilled in the art may appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein may be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed by hardware or software methods depends on the specific application and design constraints of the technical solution.

[0094] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, and may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0095] The above description is only a specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application.

Claims

1. A DC loop resistance test system, It is characterized in that include: An intelligent test module, which is electrically connected to the data analysis module and is used to perform a resistance test on the resistance to be tested according to preset output parameters, collect the measured voltage and measured current of the resistance to be tested during the test, and send the measured voltage and measured current to the data analysis module; A data analysis module, which is electrically connected to the data comparison module and is used to generate an observation window that is adjusted in real time, calculate an average measurement voltage and an average measurement current based on the measurement voltage and the measurement current, perform analysis, and send the analysis result to the data comparison module; A data comparison module, the data comparison module is electrically connected to the data calibration module, and is used to compare the analysis result with a preset dynamic threshold, generate a control signal according to the comparison result, and send the measured voltage and the measured current to the data calibration module; A data calibration module, the data calibration module is electrically connected to the temperature calibration module and the data transmission module, and is used to substitute the measured voltage and the measured current into a preset algorithm to generate a calibration coefficient when receiving a control signal, and then adjust the abnormal average measured voltage and average measured current according to the calibration coefficient, calculate the measured resistance according to the adjusted average measured voltage and average measured current, and send the measured voltage, measured current, and measured resistance to the data transmission module; A temperature calibration module, the temperature calibration module comprising a temperature sensing unit and a temperature calibration unit, the temperature sensing unit being electrically connected to the temperature calibration unit and being used to measure the ambient temperature of the environment in which the resistor to be measured is located, the temperature calibration unit being electrically connected to the data calibration module and being used to calibrate the measured resistor according to the ambient temperature; A data transmission module, which is communicatively connected to the data display module and is used to send the measured voltage, measured current, and calibrated measured resistance to the data display module; The data display module is used to visually display the measured voltage, measured current, and calibrated measured resistance.

2. A DC loop resistance testing system according to claim 1, Features: The calculation method for calibrating the measured resistance is: b c ′ =b c ×[1+a(T c -T 0 )] Where R c , R c ′ They represent the measured resistance before calibration and the measured resistance after calibration respectively, a represents the preset resistance temperature coefficient, T c Indicates the ambient temperature, T 0 Indicates the preset reference temperature.

3. A DC loop resistance testing system according to claim 2, Features: The total number of measured voltage and current data collected is calibrated as K, and the length of the observation window is calibrated as M. When analyzing the measured voltage and current, the moving average method is used for calculation. The calculation method is: In the formula represents the average measured voltage at the kth acquisition, k∈[M,K], V c (j) represents the measured voltage at the jth acquisition; Traverse the value range of k, obtain the average measured voltage under different k values ​​and calculate the mean and standard deviation σ 1 , the calculation method is: The upper and lower limits of the dynamic threshold are generated based on the mean and standard deviation. The dynamic threshold is expressed as When there is When , it is considered that the average measured voltage is abnormal; Similarly, the moving average method is used to calculate the average measured current at the kth acquisition Then calculate the mean value based on the average measured current under different k values and standard deviation σ 2 , and generate the corresponding dynamic threshold When there is When , the average measured current is considered abnormal.

4. A DC loop resistance testing system according to claim 3, Features: The length M of the observation window is generated by the total number K of measured voltage and current data acquisition, and is calculated as follows:

5. A DC loop resistance testing system according to claim 3, Features: The method for calibrating abnormal measurement voltage and measurement current is as follows: Substitute the measured voltage and current in the observation window into the preset fitting error model to generate the calibration coefficient μ; The calibration coefficient μ is used to calibrate the abnormal average measured voltage and average measured current. The calculation method is: In the formula Respectively represent the average measured voltage and average measured current after calibration. They represent voltage error and current error respectively, and are calculated as follows: In the formula represent the expected voltage and expected current respectively, where Among them I 0 Indicates the preset standard current, R 0 Indicates the preset standard resistance.

6. A DC loop resistance testing system according to claim 5, Features: The fitting error model is calculated using the least squares method, and the calculation method is: The average measurement voltage and average measurement current are repeatedly calibrated using the calibration coefficients and the average values ​​of the calibrated average measurement voltage and average measurement current are recalculated. When the calibrated average measurement voltage, average measurement current and corresponding average values ​​all meet The calibration is considered complete when 7. A DC loop resistance testing system according to claim 6, Features: Calculate the measured resistance R according to the average values ​​of the average measured voltage and average measured current after calibration. c , 8. A DC loop resistance test method, It is characterized in that The test method is performed by the test system according to any one of claims 1 to 7, and the specific steps include: S1: Perform resistance test on the resistor to be tested according to the preset standard current and standard resistance set by the user, and collect the measured voltage, measured current and ambient temperature of the resistor to be tested during the test; S2: Generate an observation window according to the total number of data collected for the measured voltage and the measured current, calculate the average measured voltage and the average measured current in the observation window, then slide the observation window to generate different average measured voltages and average measured currents, and calculate the corresponding mean and standard deviation; S3: Substituting the average measured voltage and average measured current in different observation windows into a preset fitting error model to generate a calibration coefficient, and then generating a dynamic threshold according to the mean and standard deviation of the average measured voltage and average measured current, and comparing the average measured voltage and average measured current with the dynamic threshold to find abnormal data in the average measured voltage and average measured current; S4: Use the calibration coefficient to calibrate the abnormal average measurement voltage and average measurement current, and calculate the corresponding measurement resistance. Then, perform temperature calibration on the measurement resistance according to the ambient temperature, generate the calibrated measurement resistance and display it visually.

9. A loop resistance tester, Features: The loop resistance tester comprises the DC loop resistance test system according to any one of claims 1 to 7.

Images