Evaluation for Computerized Data Acquisition Systems of Universal Testing Machines
Some standard content:
National Metrology Technical Regulation of the People's Republic of China JJF1103—2003 Evaluation for Computerized Data AcquisttionSyslems of Uaiversal Testing Machines Issued on 2003-05-12 Implementation on 2003-09-12 Issued by the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China JJF1103—2083 Evaluation for Computerized Data Acquisition Systens of Universal Testing Machines JJF1103—2003 This specification was approved by the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China on May 12, 2003, and came into force on September 12, 2003.
Responsible for: National Technical Committee on Force and Hardness Metrology Main drafting unit: China Iron and Steel Research Institute
Participating drafting unit: National University of Defense Technology, China Institute of Metrology
The responsible unit for this standard is responsible for interpretation
Main drafters of this standard:
Wang Chunhua
Zheng Wenlong
Zheng Jianping
Participating drafters:
Li Qingzhong
Liang Xinbang
Jiang Zhiyong
JJF 1103—2003
(General Iron and Steel Research Institute)
(School of Aerospace Materials Science and Engineering, National University of Defense Technology) (General Iron and Steel Research Institute)
(National Institute of Mass Science)
(General Iron and Steel Research Institute)
(General Iron and Steel Research Institute)
(General Iron and Steel Research Institute)
2 References…
3 Technical Discussion and Definitions·
Basic Data·
Handbook
3.3 Sampling Rate
Resolution
Sensor-Channel Bandwidth
Screening Machine Data Acquisition System
Overview:
Measuring Characteristics
Test Conditions…
Environmental conditions:
Specimen…
Testing machine indication
Frequency width
Evaluation method
7.1 Single machine comparison method-
7.2 Multi-machine comparison method
Expression of evaluation results-
9' Evaluation interval·
JJF1103—2003
Appendix A Test record of the hardware part of the computer data acquisition system Measurement uncertainty
Analysis of the difference in comparison test results
Contents of the certificate (report)
Evaluation of computer data acquisition system for universal testing machine This book is suitable for dynamic testing machine and dynamic test system. The above is called calculation validity system! The efficacy and consistency of the agent are determined by the calculation method
2 References
This standard quotes the following texts:
ssrM Sis56 - a7 Sianlarl Ctjje fry Eeslnting Girrjpurizerl nin Arjuisitiun Sruumsliserlto4gaire1refmrlirivasalThslirigMarhnet universal testing machine card computer efficiency collection system evaluation guide
CN2282 material temperature Zhongwei age (0692:1998CBT126m20K single extraction test see: Zhong designed standard d:I509513:1999)1996 electric two-way test machine
CB/T16491
CR'T1682:
1997 pull small test camel heat test (90500-.1:15866139-1999 pull, [and force testing machine calibration regulations in IG 475—1986
Electric force test machine calibration plan
IJC762—1992 Introduction to the design and calibration procedures for products, these methods are generally used in the current digital double technology. 3 Terms and definitions
A digital device aasicil
In the most common measurement of force and position, its analog world corresponds to the digital level, in the static material can be obtained from the national base array (see Figure 1):
Derived data example:
Elastic thin product
Basic data
Real limit material inspection
Figure 1 Basic data and derived data
3.2 Derived data data
F1103—203
Additional numerical values calculated by the calculation software algorithm based on the basic data. Such as peak force or elastic modulus value.
3 Data acquisition rate
The rate at which digital samples (force, deformation, displacement, etc.) are collected, expressed in samples/second, 3.4 Resolution
The smallest display difference that the display device can effectively distinguish. Connection:
1 The pharmacodynamic product is not a device, and the test is not carried out without digital display position change. 2 The comparison is required for recording the gas device.
3 Any force, deformation or displacement (for both tests), the method of computer system 3.5 Sensor-channel bandwidth Transducer-channel bandwidth The channel bandwidth of a sensor measuring force, deformation or displacement refers to the frequency at which the value drops by 3B in the amplitude-frequency characteristic curve. That is, the error of the measured signal is 30%, and the position shift is 45 or more (Figure 2) - constant value bandwidth pressure/T [2
frequency bandwidth of the source channel
Figure 2 bandwidth you
3.6 Computer data acquisition system
coniputerizescl Computer data acquisition system refers to the device which collects basic data from the performance testing machine during the test, and calculates and provides output data based on the basic data collected. This specification adopts the comparative test method to determine the computer data acquisition system. The method is to compare the basic data and output data obtained by the computer data acquisition system of the performance testing machine with the results obtained by the drawing record of the same testing machine (single-machine comparison method), or compare with the results obtained by other testing machines (multi-machine comparison method, evaluate their consistency, and determine the accuracy of the test results of the computer data acquisition system, so as to ensure the correctness of the material test results.
5 Metrological characteristics
The force values collected by the computer data acquisition system shall have an accuracy of Class 1 or above (should not be lower than the accuracy of the same universal testing machine). The accuracy level and use accuracy of the extensometer shall comply with the requirements of JJ762-1592, G2160-2002 and CB/T228-2002 respectively. The relative error between the average value of the test results obtained by the computer data acquisition system and the average value of the test results calculated manually, or the half-mean value of the test results obtained by other testing machines, should not exceed ±2 or 1 standard deviation (whichever is greater).
6 Test conditions
6.1 Environmental conditions
The ambient temperature is 23℃±5℃,
6.2 Samples
Select at least 5 different types of samples, representing the samples usually tested on the testing machine. Each type of sample should be cut from the same press.
1 The gears of the test machine can be divided into the following five types, 2 the test types can be distinguished by material (strength), size, condition or test method. 6.3 Test machine indication
All display or indicator devices and recording devices on the test machine (including computerized test equipment) shall be verified or tested in accordance with JFC139-1999, JC475-1986, JC762-1992, CB/T16825-1997 and GB/T12160-2002.
6.4 Bandwidth
All sensors connected to the display device or recording device (or both), including the drawing and recording device, shall meet the required bandwidth (see Chapter A2 of Appendix A). 7 Evaluation method
7.1 Single comparison method
7.1.1 This method uses a test machine that can manually calculate the test results (derive the data) by drawing and recording: .1.2 The testing machine shall be equipped with a graphical device capable of recording the test process. The records in the graphical device may be generated manually by analog signal sources, computer data acquisition systems, or based on the basic data recorded by the system. 7.1.3 At least five specimens of each type shall be tested, and the results obtained by the graphical record and the computer data acquisition system shall be obtained simultaneously.
7, [.4] The same test results obtained by manual calculation based on the graphical record and the computer data acquisition system. 7.1.5 According to the results of manual calculation of each group of 5 samples and the results obtained by the computer data acquisition system, the average value, standard deviation and relative reading error are calculated by formula (1), formula (2) and formula (3), respectively, x
（-）
.F11(03-20M13
x-*+100%
where: x——the average value of n tests;
8——the standard deviation of n tests;
the relative difference between the average value obtained by the computer data acquisition system and the average value obtained by manual calculation;
——the average value of the test results obtained by the computer data acquisition system;
——the average value of the test results obtained by manual calculation. 7.! 6 And the ministers of the teaching technical collection system to obtain the average value of the collection and the average value obtained by manual calculation of the case exceeds the two calculations of the standard case or exceeds the two calculations of the standard case (the larger value!, should find the reason, and will be F:
7 out of the summer, should benefit from the computer data to collect the most comprehensive results of the standard deviation of the results obtained by the standard deviation, then the reason should be corrected. 7.2 Multi-machine ratio method
2.1 Except for the test of the English hole number with a soft case system, the test machine or other test set should be added with 1 time: the test machine is not necessarily equipped with a calculation Kai data collection system. The final negative mood is to resist the internal problems with some benefits. .2.2 The test is to record the average test process of the equipment with room matching performance , the equipment can record the source of the simulated information, please calculate the steam turbine data according to the standard station data generated by the system or according to the statistical record. 72.3 The dynamic efficiency model of the test age is compared with the test age machine on the base of 5 samples of the same test age, the following standard, the customer test
7 years of bench test machine test, by the calculation of the data acquisition system and the mountain two devices through the record! Or two requests! I get the test results:
7.2.5 The test area records the data of the system to collect the data of the system, 72.6 The scale is ≤3 samples or more (selected by the tester) manually! The calculation results and the calculation data collection system are summarized:, respectively (1), (2) (3) calculate the average value of one, and the standard is set relative to the difference. 72 If the calculation method requires the normal system, The single mean value of the set is compared with the manually calculated mean value, or the value obtained by other verification machines is more than +2% of the mean value. The deviation (the maximum value) is calculated. The original proposal is to find out the cause, and the calibration will be stopped.
72. If necessary, find out the cause! The single machine number is the standard deviation of the standard, and the most accurate one is obtained by the test machine. The standard deviation is the previous page of the country, and the calibration will be started. The new one can be used in Beijing. The "reading modification will help the version 5 of the third road of the third road" will be the price of the station. The evaluation results must be expressed in the form of a training book: its content is shown in Appendix 4
Evaluation time interval
JF 1103—2003
The user can determine the evaluation time interval according to the actual use situation, and the test machine and extensometer verification can be carried out at the same time. However, after the operation and software of the computer data acquisition system are replaced, the evaluation should be carried out immediately. Appendix A
JJF1103—2003
Testing of the hardware part of the computer data acquisition system A.1 Matters to be considered by the tester
1.1 It is important to clarify the transmission method of information between the test systems so that the system can be properly tested and calibrated. The information transmission between the test system components is either digital or analog. A.1.1.1 The transmission of test results from the computer to the printout is an example of the mathematical transmission of data between test systems. In some cases, the digital system of the testing machine can transmit data and other data to a computer. A.1.1.2 The signal produced by the force sensor is also transmitted to an amplifier in the testing machine, where the signal is converted into a single signal. This is an example of analog transmission of data. The testing machine converts the applied force into a voltage proportional to the applied force and transmits it to an analog XY recorder 1, which is also an example of analog transmission of data. A.1.2 An analogue-to-digital converter (A/D) converts analogue signals into digital signals, and a digital-to-analogue converter (DAC) converts digital signals into analogue signals. It is common for a modern test machine to use one or more of these converters. Every point in the system that uses A/D or D/A transmission data may need to be tested. The tests can be carried out on either side of the converter screen, or on either side of the converter screen. A.1.3: In most cases, if digital signals are received from a proven digital device without A/D or D/A transmission (such as a printer and video camera), the receiving device will be passive and will not require routine assessment after replacement. A.1.4 From the electrical system schematic, form the test system block diagram with all sensors and all data inputs given by the manufacturer and identify the test points. Mark the required test points on the test machine: During routine testing, all test points shall be tested to ensure the reliability of the data output by the verification system. 1.2 Test System Accuracy
1.2.1 Bandwidth and data acquisition accuracy are two factors that affect the system's response to dynamic changes. This specification requires the determination of the minimum bandwidth to determine the minimum data set rate. 1.2.2 When the system response and test conditions are determined, there are two bandwidths to consider: the bandwidth derived from the test equipment and the sensor-channel bandwidth as a function of the test machine. 1.2.3 The sensor-channel bandwidth shall be equal to the predicted bandwidth. To obtain high accuracy, the measured signal (excluding noise) shall not be close to the frequency distribution of the sensor-channel bandwidth. 1.2.4 Required Bandwidth
It is difficult to give an accurate minimum value for the required bandwidth, but it is important to ensure that the response observed in the test is not limited by bandwidth variations. In particular, this may damage the performance of the system, resulting in reduced accuracy and possible increase in noise. On test items specified in test methods such as 22, a bandwidth of at least 0.2 Hz is sufficient. A simple method for assessing the required bandwidth is as follows: The system is evaluated for the duration of the process [shift] during which the result is obtained (with a minimum error of 1% absolute value). This result is the peak force or elastic modulus of the stress-strain curve (see Figure Al). b) For signals with larger variations, the required bandwidth (Hz) is given by equation (A1): 3
New required bandwidth "time
US estimate ||t t||JJE11032003
but when [,/s
is to select the average duration
4-digit Ningnan value
to build the duration of the remaining medical time base
Figure F time
) When there is a bee at a certain time, in order to collect the peak point, the required sequential speed (: can be directly calculated by the formula ():
The required width is a delay time 4.2.5 Special exposure device channel bandwidth
Testing machine manufacturers should say muscle sensor channel section detection: if the digital filter cover will lead to the improvement of the section, the manufacturer should use the sensor data through the technical method of tie detection to calculate the bandwidth of the system. Any testing machine fire head time note board first, book fold pull strong! The steel wire (single strand) is stressed until the steel wire breaks. A digital or analog oscilloscope is used to collect the instantaneous step waveform. The linear interpolation method is used to find the difference between the 10% average point of the step sequence. If the time is less than the interval between two data points, the time between the two data points is used as the output time: The bandwidth of this system is calculated according to formula (43):
sensor channel bandwidth = 0.34
A.2.6, 1 good method provides a high enough data collection rate, so the system response can be measured by digital sampling step response,
.2.62 The above method is only sufficient to verify the bandwidth of the test. The sample response curve is compared with the output of the high-speed high-strength green break. If the rate of change of the line is similar to the rate of change of the high-strength line, the response curve will be wrong because the measured response is the characteristic of the test: it represents the characteristic of the reduction. 4.2.7 The data collection rate is calculated according to formula (4): where: f
JJF 1L0L3-—2003
1(1%-1% rise time of simulated wave
time/5
10%-90% rise time of digital waveform
Use linear internal capture method to estimate 100% two points
Figure A2 level virtual
time/5
fu\K (most Re)·
Minimum data acquisition rate, 175:
Stress speed test, N/m-,
Rr——Use service strength, N/m n;
Standard non-specific tensile strength, N/mm;
9——Relative error of the testing machine,
A.3 Resolution of the test systembZxz.net
4.3.1 The resolution of a digital test system is usually a complex number including many variables, not limited to the applied force, force range, electrical and mechanical components, electrical and mechanical noise, and applied software. A.3.2 The resolution can be determined from the electrical system schematic or from the description of the computer system resolution obtained from the test system manufacturer.
A.3.3 Test the system to ensure that the specified resolution is obtained. The resolution of the data collected can be checked by different methods:
A, 3.4 Use a magnetic or calibrated force gauge to apply a force to the system, and collect data at the same time. Apply force at half the resolution provided by the system, repeat several times, and observe the change in force from the indicating device. Use similar steps to test the strain resolution with an extensometer calibrator, and use a higher-level displacement device to check the position resolution. A.3.5 Test the results A.3.6 The system cannot report derived data where the relative resolution is worse than 1/200 compared to the indicated resolution. However, basic data with relative resolution worse than 1/200 can be used to find derived data points. For example, in the initial elastic part of the stress-strain curve, the vertical part of the digitized curve can be used to calculate the image stress. The data used to establish the curve can have a relative resolution worse than 1/200, but the reported image stress must be in the area where the relative resolution is better than 1/200:
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