A method of detecting a digital weight display

Abstract

The application discloses a detection method of a digital weighing display, a digital weighing display test system based on a strain type weighing sensor simulator, and the digital weighing display test system comprises a strain type weighing sensor simulator, an A / D analog-digital converter, an analog display device and a digital weighing display. The detection method comprises the following steps: confirming a nominal load value I0 corresponding to an output signal C0 of the weighing sensor simulator; confirming a weighing value I1 received by the analog display device and a weighing value I2 output by the analog display device according to analog signal information output by the weighing sensor simulator; confirming a display weighing value I3 of the weighing display; and judging whether the digital weighing display meets the standard or not. The method can compensate for the requirement that the output signal of the weighing sensor simulator used for detecting the digital weighing display is completely linear, and can better detect the measurement performance of the digital weighing display.

Description

Technical Field

[0001] This invention relates to the technical field of weighing and measurement testing, and in particular to a testing method for a digital weighing display. Background Technology

[0002] The weighing indicator is a key component of weighing instruments, playing a crucial role in the quality of the product. To complete a weighing operation, two main parts are necessary: ​​a load cell and a weighing indicator. A digital weighing indicator (weighing display) is an electronic device that performs analog-to-digital conversion (optional) and further data processing on the output signal of the load cell, displaying the weighing result. Conventionally, they are divided into two categories: digital and analog. A display that receives digital signals is a digital weighing indicator, while a display that receives analog signals is an analog weighing indicator. Both digital and analog weighing indicators use digital indication. For digital weighing indicators, the error distribution coefficient p... i It is 0.

[0003] Early testing methods for weighing indicators mainly included the voltage source method, potentiometer method, and sensor method. The biggest problem with the first two methods was that they disregarded the overall "voltage ratio" technology of the indicator, artificially and rigidly testing each component separately before combining the results; this method is outdated. The sensor method suffers from low accuracy and the inconvenience of carrying the associated force source. Given the aforementioned shortcomings of the voltage source method, potentiometer method, and sensor method, the high-precision calibrator method (hereinafter referred to as the "calibrator method" or "weighing sensor simulator method") was developed. International metrology organizations have fully affirmed and recommended this method, and the United States, Japan, and the European Union have implemented it with excellent results. my country has also adopted the weighing sensor simulator method for testing weighing indicators. A weighing sensor simulator is a device that simulates the standard output signal of a weighing sensor, used to test analog and digital weighing indicators (requiring an A / D converter). Strain gauge weighing sensor simulators can be divided into two categories: infinite display and digital display.

[0004] Since the weighing indicator is one of the main independent modules in a non-automatic weighing instrument, OIML R76-2006(E) "Non-automatic Weighing Instruments", National Type Evaluation Outline JJF 1624-2017 "Type Evaluation Outline for Digital Weighing Indicators (Weighing Indicators)", National Verification Regulation JJG 649-2016 "Digital Weighing Indicators (Weighing Indicators)", and National Standard GB / T 7724-2008 "Electronic Weighing Instruments" all clearly state that its error limit should maintain a linear proportional relationship with the maximum permissible error of the matching weighing instrument of the same accuracy level (multiplied by the error distribution coefficient p of the weighing indicator). i Analog weighing indicator p iThe standard value is 0.5, while the digital weighing display is p. i =0.

[0005] When the weighing indicator has a scale division value less than or equal to 0.2e ind When extending the display device, the formula for the indication error at its load point is E = IL, where E is the indication error; L is the nominal load; I is the indication value under that load L; e ind This refers to the calibration scale division of the weighing indicator. When the weighing indicator does not have a scale division less than or equal to 0.2e... ind When using a display device, the detection method is based on the flicker point method to determine the indication error of the load point (the calculation formula for this method is E = I + 0.5e). ind -ΔL-L), where E is the indication error before rounding; L is the nominal load; I is the indication under load L; ΔL is the additional load. ΔL is obtained by applying loads equivalent to 0.1d one by one. ind (d ind The load (the actual scale division of the weighing indicator) is applied until the indicated value significantly increases by one scale division (I+e). ind The accumulated load is obtained. For a weighing indicator, the load mass in its basic formula of the flicker point method can be represented by the equivalent verification scale number n of the weighing indicator. Without loss of generality, the actual scale value d ind and the verification scale value e ind It can be set to dimensionless 1, and the load mass L can be equivalent to the corresponding verification division number n = L / e. ind Or use the corresponding test scale n = L / e ind To represent. The additional load ΔL is 0.1(e ind Multiples of 1, generally between 1 and 10. From E = I + 0.5e ind From -ΔL-L, we can see that when I=L, only 0.5e ind –E will be 0 only when ΔL=0 is true, at which point a load of 0.1(e) is applied. ind The number of times ) can be used is only 5. 0.1(e) ind ) and an important parameter Δu of the weighing display during the test ind Related to Δu ind It is each test scale value e ind The corresponding minimum input signal voltage, i.e., 0.1 (e ind The additional load value and the corresponding input signal voltage value 0.1Δu ind Equivalent.

[0006] When testing digital weighing indicators using the conventional testing methods described above and performing linear calibration, it is difficult to guarantee 100% linearity after calibration. This means it's difficult to guarantee that the indication error E at each load point L (represented by the number of calibration divisions n) applied by the digital weighing sensor (or a weighing sensor simulator + A / D converter) will be zero. Secondly, when using the flicker point method for a load point test, since the maximum allowable tolerance is 0, to meet this requirement in actual testing, it is necessary to ensure that each test increment is 0.1 (e... ind When a small load (or equivalent additional output signal) is applied 5 times, the condition is exactly met: the weighing display reading increases by 1 d. ind Obviously, this testing method cannot guarantee that every load point will meet the condition 100%, meaning that the flicker point method is not very suitable for testing digital weighing indicators. This inapplicability contradicts the principle that the flicker point method can be used in principle to detect typical load point indication errors of non-automatic weighing instruments and weighing indicators. Therefore, it is necessary to find another way to implement the flicker point method for testing digital weighing indicators. Summary of the Invention

[0007] In order to overcome the existing technical defects and solve the problems that the maximum permissible error of digital weighing indicators is 0 and that it is difficult to use the flicker point method for testing, the purpose of this invention is to provide a testing method for digital weighing indicators to solve the above-mentioned technical problems.

[0008] The technical solution adopted by this invention to solve the technical problem is as follows:

[0009] According to one aspect of the present invention, a testing method for a digital weighing indicator is designed, and a digital weighing indicator testing system based on a strain gauge weighing sensor simulator as the testing standard is provided, the digital weighing indicator testing system comprising:

[0010] A weighing sensor simulator is used to output an analog signal C0, and can establish a linear relationship between the output signal C0 and the nominal load I0 through calibration.

[0011] An A / D analog-to-digital converter is used to receive the analog signal, convert it into a digital signal, and output the digital signal.

[0012] An analog display device is used to receive the digital signal output by the A / D analog-to-digital converter and convert the digital signal into a weight display and output it, wherein the analog display device outputs the same digital signal as the A / D analog-to-digital converter.

[0013] A digital weighing indicator is a weighing display that can receive digital signals, and its error distribution coefficient p i=0, used to receive the output information of the analog display device, process it, and then display the weight;

[0014] The detection method includes:

[0015] The output signal C0 of the strain gauge load cell simulator is identified, with the unit symbol mV / V. The nominal load value I0 corresponding to this output signal is also determined.

[0016] The analog signal output from the weighing sensor simulator is converted into a corresponding digital signal by an A / D analog-to-digital converter.

[0017] The simulation display device determines the received weighing value I1 and the output weighing value I2 of the simulation display device based on the simulation signal output by the receiving weighing sensor simulator.

[0018] The digital weighing indicator is calibrated after receiving the digital signal output from the analog display device. After calibration, the displayed weighing value I3 of the digital weighing indicator is confirmed.

[0019] Criteria for determining whether a digital weighing indicator passes inspection:

[0020] If the indication error of the nominal load point corresponding to the I3 value does not exceed the maximum allowable error of the analog weighing display of the same accuracy class, the error distribution coefficient pi is not equal to 0, and the difference between the displayed values ​​of I2 and I3 is 0, then the indication error of the load point of the weighing display is deemed to be qualified.

[0021] Alternatively, if the difference between the displayed values ​​of I2 and I3 is 0, while the difference between the displayed values ​​of I0 and I3 is not 0, and the absolute value of the difference does not exceed the maximum allowable tolerance of an analog weighing display of the same accuracy class, and the error distribution coefficient pi is not equal to 0, then the indication error of the weighing display at this load point is deemed acceptable; if the difference between the displayed values ​​of I2 and I3 is not 0, or the absolute value of the difference between the displayed values ​​of I0 and I3 exceeds the maximum allowable tolerance of an analog weighing display of the same accuracy class, and the error distribution coefficient pi is not equal to 0, then the indication error of the digital weighing display at this load point is deemed unacceptable.

[0022] To better address the aforementioned technical deficiencies, the present invention also provides a more advanced technical solution:

[0023] In some embodiments, the analog display device includes a digital input module, a processor module, a display module, and a digital output module. The digital input module is connected to the A / D converter, which outputs a digital signal to the digital input module. The processor module processes the digital signal input from the digital input module, converts the digital signal into a weight display, and sends the processed information to the digital output module. The display module displays I1 and I2. The digital output module outputs the same digital signal as the A / D converter and sends the digital signal to the digital weighing display.

[0024] In some implementations, I1 represents the displayed value of the digital signal input from the A / D converter after weight conversion, and the zero point and coefficient of the weight conversion calibration of the A / D converter are the same as those of the digital weighing display. I2 represents the value displayed on the interface after weight conversion following linear calibration of the digital signal input from the A / D converter. I3 represents the weight value displayed after weight conversion following reception of the digital signal output from the analog display device by the weighing display. The weight conversion algorithm of the analog display device must be the same as that of the digital weighing display, and the zero point and coefficient must be the same.

[0025] In some implementations, the linear calibration includes: at least two points, zero point and full scale; or multi-load point calibration.

[0026] In some implementations, the difference between the displayed values ​​of I2 and I3 being 0 requires the following condition to be met:

[0027] a. The zero point and coefficient of the analog display device must be the same as those of the digital weighing display.

[0028] b. The zero-point tracking function of the digital weighing indicator must be turned off;

[0029] c. The coefficient accuracy of the analog display device is equal to that of the digital weighing display.

[0030] d. The analog display device and the digital weighing indicator use the same digital filtering algorithm;

[0031] e. The A / D converter, analog display device, and digital weighing indicator need to be warmed up for 10 minutes.

[0032] In some implementations, the flicker point method, which is generally applicable to analog weighing displays, can be used for detection without considering its error distribution factor p. i The impact of setting it to 0.

[0033] The beneficial effects of this invention are as follows: Currently, testing digital weighing indicators no longer requires static temperature tests and damp heat / steady-state tests. Because this invention does not require the maximum allowable error and indication error under the test load to necessarily be zero (i.e., I0 and I3 do not need to be completely equal), but rather requires meeting certain conditions (the difference between I0 and I3, or the error after error correction, must meet the maximum allowable error requirements of analog weighing indicators of the same accuracy class; I2 and I3 must be completely identical, just like the transmission of pure digital signals) to meet the testing requirements. Therefore, static temperature tests and damp heat / steady-state tests can be performed. Furthermore, through linear calibration of the analog signal, the digital signal received by the weighing indicator under test can achieve higher sensitivity, compensating for the insufficient sensitivity of the weighing sensor simulator and the requirement for the output signal of the weighing sensor simulator used in testing digital weighing indicators to be completely linear (100% linearity). The flicker point method can be used for testing digital weighing indicators, enabling better detection of the metrological performance of digital weighing indicators. In practice, this allows for more effective, convenient, and accurate confirmation of whether the testing performance of digital weighing indicators is qualified. Attached Figure Description

[0034] Figure 1 A schematic diagram of the structure of a digital weighing display testing system according to one embodiment of the present invention;

[0035] Figure label:

[0036] 1. Weighing sensor simulator; 2. A / D analog-to-digital converter; 3. Analog display device; 4. Digital weighing indicator. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments and the accompanying drawings. It should be understood that these descriptions are merely exemplary and not intended to limit the scope of the invention. Furthermore, descriptions of well-known structures and techniques are omitted in the following description to avoid unnecessarily obscuring the concept of the invention.

[0038] In the description of this invention, it should be understood that the orientation descriptions, such as up, down, front, back, left, right, etc., are based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0039] In the description of this invention, unless otherwise explicitly defined, terms such as "set up," "install," and "connect" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this invention in conjunction with the specific content of the technical solution.

[0040] refer to Figure 1 As shown, the present invention provides a testing method for a digital weighing display, and a digital weighing display testing system based on a strain gauge weighing sensor simulator. The weighing display testing system includes: a weighing sensor simulator 1, an A / D analog-to-digital converter 2, an analog display device 3, and a digital weighing display 4.

[0041] The load cell simulator receives the excitation voltage from the load cell display and converts it into an analog signal voltage, then outputs an analog signal C0 and determines the nominal load value I0 corresponding to the analog signal.

[0042] The A / D converter is connected to the weighing sensor simulator in one-way or two-way communication. The A / D converter is used to receive the analog signal output by the weighing sensor simulator, convert it into a digital signal, and output the digital signal.

[0043] The analog display device is unidirectionally or bidirectionally connected to the A / D converter. The analog display device receives the digital signal output by the A / D converter and processes and converts the digital signal into a weight display for output. The analog display device outputs the same digital signal as the A / D converter. Further, the analog display device includes a digital input module, a processor module, a display module, and a digital output module, all connected in communication. The digital input module is connected to the A / D converter and outputs a digital signal to the digital input module. The processor module processes the digital signal received from the digital input module, converts the digital signal into a weight display, and sends the processed information to the digital output module. The display module displays the weight value after weight conversion of the digital signal received from the A / D converter and the weight value after weight conversion following linear calibration of the digital signal from the A / D converter by the processor module. The digital output module outputs the same digital signal as the A / D converter and sends the digital signal to the digital weighing display.

[0044] A digital weighing indicator is a weighing indicator that can receive digital signals, and its error distribution coefficient p i =0, connected to the analog display device in one-way or two-way communication, used to receive the output information of the analog display device and process it to display the weight.

[0045] The testing methods for digital weighing indicators include:

[0046] The load cell simulator acquires the excitation voltage information of the weighing display. Based on the weighing information and calibration method, it confirms the output signal value C0 of the load cell simulator and the corresponding nominal load value I0. The unit of the output signal C0 is mV / V.

[0047] The analog signal output from the weighing sensor simulator is converted into a corresponding digital signal by an A / D converter.

[0048] The analog display device determines the received weighing value I1 and the output weighing value I2 based on the analog signal information output by the weighing sensor simulator. I1 represents the displayed value after weight conversion of the digital signal input from the A / D converter, and I2 represents the value displayed on the interface after weight conversion following linear calibration of the digital signal input from the A / D converter. Furthermore, the analog display device includes a digital input module, a processor module, a display module, and a digital output module connected in communication. The digital input module is connected to the A / D converter, which outputs digital signals to the digital input module. The processor module processes the digital signals input from the digital input module, converting them into a weight display value and sending the processed information to the digital output module. The display module displays I1 and I2, and the digital output module outputs the same digital signal as the A / D converter and sends this signal to the weighing display.

[0049] The digital weighing indicator performs linear calibration after receiving the digital signal output from the analog display device. Linear calibration includes two-point calibration, zero-point calibration, and full-scale calibration, or multi-load-point calibration. After calibration, the displayed weighing value I3 is determined. I3 represents the weight value displayed after the signal output from the analog display device is received by the weighing indicator and converted. The weight conversion algorithm of the analog display device must be the same as that of the weighing indicator, and the zero point and coefficient must be identical.

[0050] Criteria for determining whether a digital weighing indicator passes inspection:

[0051] If the indication error of the load point corresponding to the I3 value does not exceed the maximum allowable error of the same load for an analog weighing display of the same accuracy class, and the error distribution coefficient pi of the weighing display is not equal to 0, and the difference between the displayed values ​​of I2 and I3 is 0, then the indication error of the load point of the weighing display is deemed to be qualified.

[0052] Alternatively, if the difference between the displayed values ​​of I2 and I3 is 0, while the difference between the displayed values ​​of I0 and I3 is not 0, and the absolute value of the difference does not exceed the maximum allowable tolerance of the same load for analog weighing indicators of the same accuracy class, then the error distribution coefficient pi of the weighing indicator is not equal to 0, and the indication error of the weighing indicator at this load point is deemed to be qualified; if the difference between the displayed values ​​of I2 and I3 is not 0, or the absolute value of the difference between the displayed values ​​of I0 and I3 exceeds the maximum allowable tolerance of the same load for non-automatic weighing instruments of the same accuracy class, then the error distribution coefficient pi of the weighing indicator is not equal to 0, and the indication error of the weighing indicator at this load point is deemed to be unqualified.

[0053] Furthermore, for the difference between the displayed values ​​of I2 and I3 to be 0, the following condition must be met:

[0054] a. The zero point and coefficient of the analog display device must be the same as the zero point and coefficient of the weighing display.

[0055] b. The zero-point tracking function of the weighing indicator must be turned off;

[0056] c. The accuracy of the coefficients of the analog display device is equal to the accuracy of the coefficients of the weighing display.

[0057] d. The analog display device and the weighing indicator use the same digital filtering algorithm;

[0058] e. The A / D converter, analog display device, and weighing indicator need to be preheated for 10 minutes.

[0059] Example

[0060] Tested instrument: Digital weighing display, accuracy class: Maximum number of verification divisions n ind =3000, actual scale division value d ind and the verification scale value e ind All are set to 1. For non-automatic weighing instruments of the same accuracy class, the maximum permissible tolerance MPE at load point n = 200 is 0.5e. ind Meanwhile, for analog weighing indicators of the same accuracy, the maximum allowable tolerance MPE at a load n=200 is 0.5e. ind *p ind =0.25e ind =0.25, the error distribution coefficient p of a typical analog weighing indicator. ind The default value is 0.5.

[0061] 1. Testing method for weighing indicators based on weighing sensor simulator:

[0062] Using a load cell simulator with a display function as the test standard, after wiring, the excitation voltage U of the load cell simulator... exc 5V, Δuind = 3 μV / e ind . The maximum verification division number n of the weighing indicator ind = 3000.

[0063] Calibration: 0.2 mV / V corresponds to the nominal load (expressed by the verification division number n), n = 0, 2 mV / V corresponds to the nominal load n ind = 3000. When the output signal value of the load cell simulator is 0.5 mV / V, the corresponding nominal load n = 500; when the output signal value is 1.4 mV / V, the corresponding nominal load n = 2000. If the assumed verification scale interval is 1 ( / kg), the normal display of the weighing indicator should be 500 ( / kg). Using the weighing indicator to subdivide into 0.1 d ind Or the indicator has a scale interval not greater than 0.2 e ind Extended display device, for example, its indication value is 500.0 ( / kg) or 500.1 ( / kg), and its indication error can be directly calculated (0.0 or 0.1 respectively); or the flicker point method is used to calculate the indication error at the load point 500. The maximum allowable error at this load point of non - automatic weighing instruments under the same accuracy class is 0.5, and the maximum allowable error at the load point 500 of analog weighing indicators under the same accuracy class is 0.25.

[0064] When the weighing indicator shows subdivision (0.1 d ind ) or the indicator has a scale interval not greater than 0.2 e ind Extended display device, if the difference between the display values of I2 and I3 is 0, while the difference between the display values of I0 and I3 can be non - zero, and the absolute value of the difference does not exceed 0.25 (0.25 e ind ), the weighing indicator is qualified at this load point n = 5 / kg. If the difference between the display values of I2 and I3 is non - zero, or the absolute value of the difference between the display values of I0 and I3 exceeds 0.25 (0.25 e ind ), the indication error of the indicator at this load point is unqualified.

[0065] When using the flicker point method, each time add a load value equivalent to 0.1 e ind (or the equivalent output signal voltage of the load cell simulator 0.1Δu ind , unit mV; or the output signal 0.1Δu ind / U exc , unit mV / V). When after a certain number of times of adding 0.1 e ind load or 0.1Δu ind input signal voltage value, I2 and I3 increase synchronously by one scale interval e ind . If the difference between the true values shown by I0 and I3 calculated by the flicker point method does not exceed 0.25 e indAt that time, the load point indication error of the weighing display is within acceptable limits. If the weighing display shows an increase of one division value e... ind However, the changes in I2 and I3 are not synchronized, or the difference between the actual values ​​of I0 and I3 calculated after the flicker point change exceeds 0.25e. ind At that time, the display failed the error detection test for this load point n=500.

[0066] 2. Testing method for weighing displays based on digital load cells or (or analog load cells + A / D converter):

[0067] The aforementioned weighing sensor simulator can also be replaced by a digital weighing sensor.

[0068] Based on a digital weighing sensor and weights, after calibration, when the verification scale value is 1kg and a nominal weight of 200kg (equivalent verification scale number n = 200) is applied, I1 displays 200kg, and I2 and I3 both display 200kg. After adding a small weight of 0.1kg, after adding the small weight six times, I1 displays 201kg, and I2 and I3 both display 201kg. At this point, the indication error at the load point is not 0kg, but -0.1kg. According to current testing methods, the load point L (equivalent verification scale number n) on the weighing display is unqualified. However, if the implementation method of this invention is used, as long as the indication error of the load point corresponding to the I3 value does not exceed the maximum allowable error of an analog weighing display of the same accuracy class (the maximum allowable error of the same load point of a non-automatic weighing instrument of the same accuracy multiplied by the error distribution coefficient p), the error is acceptable. ind =0.5, which is 0.25e ind If the load is 0.25kg and the difference between the displayed values ​​of I2 and I3 is 0, then it can be determined that the indication error of the load point on the weighing display is acceptable.

[0069] The above descriptions are merely some embodiments of the present invention. For those skilled in the art, various modifications and improvements can be made without departing from the inventive concept of the present invention, and these all fall within the protection scope of the present invention.

Claims

1. A detection method for a digital weighing indicator, characterized in that, A digital weighing display testing system based on a strain gauge weighing sensor simulator as the testing standard, the digital weighing display testing system comprising: A weighing sensor simulator is used to output an analog signal C0, and can establish a linear relationship between the output signal C0 and the nominal load I0 through calibration. An A / D analog-to-digital converter is used to receive the analog signal, convert it into a digital signal, and output the digital signal. An analog display device is used to receive the digital signal output by the A / D analog-to-digital converter and convert the digital signal into a weight display and output it, wherein the analog display device outputs the same digital signal as the A / D analog-to-digital converter. A digital weighing indicator is a weighing display that can receive digital signals, and its error distribution coefficient p i =0, used to receive the output information of the analog display device, process it, and then display the weight; The detection method includes: The output signal C0 of the strain gauge load cell simulator is identified, with the unit symbol mV / V. The nominal load value I0 corresponding to this output signal is also determined. The analog signal output from the weighing sensor simulator is converted into a corresponding digital signal by an A / D analog-to-digital converter. The simulation display device determines the received weighing value I1 and the output weighing value I2 of the simulation display device based on the simulation signal output by the receiving weighing sensor simulator. The digital weighing indicator is calibrated after receiving the digital signal output from the analog display device. After calibration, the displayed weighing value I3 of the digital weighing indicator is confirmed. Criteria for determining whether a digital weighing indicator passes inspection: If the indication error of the nominal load point corresponding to the I3 value does not exceed the maximum allowable error of the analog weighing display of the same accuracy class, the error distribution coefficient pi is not equal to 0, and the difference between the displayed values ​​of I2 and I3 is 0, then the indication error of the load point of the weighing display is deemed to be qualified. Alternatively, if the difference between the displayed values ​​of I2 and I3 is 0, while the difference between the displayed values ​​of I0 and I3 is not 0, and the absolute value of the difference does not exceed the maximum allowable tolerance of an analog weighing display of the same accuracy class, and the error distribution coefficient pi is not equal to 0, then the indication error of the weighing display at this load point is deemed acceptable; if the difference between the displayed values ​​of I2 and I3 is not 0, or the absolute value of the difference between the displayed values ​​of I0 and I3 exceeds the maximum allowable tolerance of an analog weighing display of the same accuracy class, and the error distribution coefficient pi is not equal to 0, then the indication error of the digital weighing display at this load point is deemed unacceptable.

2. The detection method for a digital weighing indicator according to claim 1, characterized in that, The analog display device includes a digital input module, a processor module, a display module, and a digital output module. The digital input module is connected to the A / D analog-to-digital converter (A / D converter), which outputs digital signals to the digital input module. The processor module processes the digital signals input from the digital input module, converts the digital signals into a weight display, and sends the processed information to the digital output module. The display module displays I1 and I2. The digital output module outputs the same digital signals as the A / D converter and sends these digital signals to the digital weighing display.

3. The detection method for a digital weighing indicator according to claim 1, characterized in that, I1 represents the displayed value of the digital signal input from the A / D converter after weight conversion. The zero point and coefficient of the weight conversion calibration of the A / D converter are the same as those of the digital weighing display. I2 represents the value displayed on the interface after weight conversion following linear calibration of the digital signal input from the A / D converter. I3 represents the weight value displayed after weight conversion following reception of the digital signal output from the analog display device by the weighing display. The weight conversion algorithm of the analog display device must be the same as that of the digital weighing display, and the zero point and coefficient must be the same.

4. The detection method for a digital weighing indicator according to claim 1, characterized in that, The linear calibration includes: at least two points, zero point and full scale; or multi-load point calibration.

5. The detection method for a digital weighing indicator according to claim 1, characterized in that, The difference between the displayed values ​​of I2 and I3 must be 0 to meet the following condition: a. The zero point and coefficient of the analog display device must be the same as those of the digital weighing display. b. The zero-point tracking function of the digital weighing indicator must be turned off; c. The coefficient accuracy of the analog display device is equal to that of the digital weighing display. d. The analog display device and the digital weighing indicator use the same digital filtering algorithm; e. The A / D converter, analog display device, and digital weighing indicator need to be warmed up for 10 minutes.

6. The detection method for a digital weighing indicator according to claim 1, characterized in that, The flicker point method, which is universally applicable to analog weighing displays, can be used to detect them without considering their error distribution coefficient p. i The impact of setting it to 0.

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