Calibration Specification for Auto-measuring System of Thermocouples and Resistance Thermometers
Some standard content:
National Metrology Technical Specification of the People's Republic of China JJF1098—2403
Calibration Specification for Auto-measuring System ofThermocouples aiid Rcsistance Thermometers2003-03-05Promulgated
Implementation on June 1, 2003
Promulgated by the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China J3F1098—2003
Calibration Specification for Auto-measuring System ofThermocouples aiid Reslstance Thermometers
JJF 1098—2003
This specification was approved by the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China on March 5, 2003 and implemented on June 1, 2003 Travel from June 1, 2017.
Responsible unit: National Temperature Metrology Technical Committee Main drafting unit: China Testing Technology Research Institute China Metrology Institute
Guangdong Metrology Science Institute
This specification is entrusted to the responsible unit for interpretation
Main drafter of this specification:
Wei Shoufang
Shen Zhengning
Participating drafter:
Chen Lixin
Chen Shiyao
Zheng Zhonghui
Gan Liangzhen
JJF 1098—2003
(National Institute of Testing Technology)
(China Institute of Metrology)
(Guangdong Institute of Metrology)
(Chongqing Institute of Instrument and Meter Materials)
(Jianjiang Dongtou Automation Instrument Factory)
(Xihang Electronic Instrument Factory)
(Tai'an Intelligent Instrument Factory)
(Zhejiang Dongtou Electrical Instrument Factory)
References··
3 Terms and measurement units
3. Standard instruments
3.2 Electrical measuring instruments
3.3 Temperature and humidity test consultation
3.4 Scanning switch ….
4.1 System composition
4.2 Purpose of the system
5 Measurement characteristics
Technical requirements for the main components of the system
5.2 Functional requirements for the dedicated measurement and display software
5.3 Safety performance
5.4 Measurement characteristics:
Mixing conditions
Environmental conditions
6.2 Standard instruments and supporting equipment for calibration
Calibration items and calibration methods
Calibration frequency
Calibration method
8 Expression of calibration results
9 Recalibration time
JJF 1098-2003
Appendix Example of Uncertainty Evaluation of Measurement Results of Standard Thermocouple Automatic Measurement System Appendix B
Example of Uncertainty Evaluation of Measurement Results of Industrial Thermal Resistance Automatic Measurement System Appendix
Calibration Certificate Cover and Inner Page Format
1 Scope
JJE1898-2003
Calibration Specification of Thermocouple and Thermal Resistance Automatic Measurement System This calibration specification applies to the calibration of S-type third-class standard thermocouple, working thermoelectric and industrial thermal resistance white dynamic measuring disk system (hereinafter referred to as system). For the calibration of R-type and B-type standard thermoelectric code measurement system, it can also be implemented as a reference. 2 References
JIG 75—1995
JJG 351—1996
JG141—2(H)
JE:229.1998
Verification procedures for standard platinum-platinum thermocouples
Verification procedures for working metal thermocouples
Verification procedures for functional metal thermoelectric valves3
Verification procedures for industrial copper and copper thermal resistors3
When using this specification, attention should be paid to the use of the current valid versions of the above references. 3 Terms and Discussion
3.1 Standard instrument
refers to standard electric regulator or standard platinum resistance thermometer3.2 Electrical measuring instrument
refers to the basic measuring instrument used to measure electrical special, such as potentiometer, digital multimeter, etc. 3.3 Constant temperature device
Generally refers to the equipment used to provide a constant temperature field, such as thermocouple tester or constant temperature bath, etc. 3.4 Scanner
Refers to the device used to switch data acquisition channels, and is called a multi-channel switch electronic scanner. 4 Overview
4.1 System composition
There are many types of thermocouple and thermoelectric automatic measurement systems. It can be integrated or composed of several parts. The typical structure is shown in Figure 1. Multi-channel data acquisition system
Standardizer
Figure 1 Real structure diagram of the measurement system
4.2 Purpose of the system
JJF1098—2003
4.3.! Standard thermoelectric automatic leakage system (hereinafter referred to as standard couple system), used to calibrate second-class standard platinum energy 10 platinum thermocouples:
4.2.2 Working thermocouple white dynamic measurement system (hereinafter referred to as T working couple system), used to calibrate working thermocouples;
4.2.3 Industrial thermal resistor white dynamic measurement system (hereinafter referred to as industrial system), used to calibrate industrial platinum and steel thermal resistors,
5 Metrological characteristics
Technical requirements for the main components of the system
5. 1.1 The markings, certificates and numbers of all components of the measurement system shall be complete, and the system composition schematic diagram and wiring diagram shall be provided. The connecting wires and connectors of all components shall be clearly marked, and the quality shall meet the actual work requirements. The plug-in shall be complete and reliable. 5.1.2 The technical requirements of the main components of the system shall meet the technical index requirements specified in the relevant verification regulations. 5.2 Functional requirements of special measurement software
5.2.1 The special measurement software shall be accompanied by an installation program, complete operation and maintenance instructions and necessary backup, which can be kept confidential. Its name, version, serial number, production date and production unit and other information shall be clearly marked: 5.2.2 The special measurement software shall have the function of saving the original measurement data and security records: the collection and verification of the measurement data and the output of the test report shall meet the requirements of the relevant verification regulations, and its original data shall not be artificially modified. The dynamic measurement system shall be able to correctly determine the temperature stability, the measurement sampling data shall be reliable, and its calibration records can be displayed, printed, saved and queried.
5.3 Safety performance
5.3.1 The insulation resistance and insulation strength of each component of the system shall comply with the provisions of CB4793.1995 Safety requirements for electronic measuring instruments: The insulation resistance of the system power supply terminal and the housing shall not be less than 2U. 5.3.2 During the measurement process, if the system freezes or fails to complete the measurement due to interference, power failure, component failure, misoperation, virus and software changes, it shall be ensured that the temperature setting is not damaged due to loss of control, and the measurement data before the failure shall be retained.
5.4 Measuring characteristics
For comparative indicators, please see the table.
Table 1 Measuring characteristics of the system
Calibration items
Sweep switch potential
Difference in data acquisition between channelsbzxZ.net
Measurement repeatability
Standard system
Operation system
Group system
2V or 2n
Standard items
Additional information
Constant quality
Verification of measurement data processing results
Calibration requirements for measuring instruments
Verification of calibration results
6 Calibration parameters
6.1 Environmental conditions
Standard code system
JJF 1098-2003
Table【Continued】
Working system
Set point modification technology sealed
Constant temperature s0.56..m
Measurement ≤0. 1%/mim
Industrial resistance system
Set point deviation does not exceed|Segment set point deviation does not exceed+5t
1i temperature 0.6C/6rnin
Measurement $0.29/mim
±2℃
Excitation es0.04110min
A number: 0,4m1
R: 2mm
In this system, the basic range should be used for calibration. The industrial resistance system should be calibrated according to the actual use of the calibration master range and meet the requirements. The uncertainty verification result should comply with the corresponding provisions in the national weight verification system table. Ambient temperature: (23±5)t
Relative humidity: ≤85%
Other conditions: not affecting the stop band calibration of the system. 6.2 Calibration standards and supporting equipment
System calibration standards and supporting equipment are shown in Table 2. 2 Calibration standard short supporting equipment
Phase point gauge
Calibration equipment
Standard instrument
(recently calibrated)
Electrical measuring instrument
Insulation resistance test power
Standard control source
Standard leakage system
First-class standard 10-
Platinum thermoelectric
First-class standard armor 10-
Platinum thermocouple
Cabinet system
First-class standard energy 10
Thermoelectric temperature (precious metal)
Second-class standard platinum fin 10-lead
Thermoelectric side (cheap metal)
Second-class standard lead 10 - Platinum
warm individual
calibrated K-type thermoelectric valve
industrial system
second-class standard resistance
grade platinum thermal resistance
0.02 grade measuring instrument or other low-voltage equipment with equivalent accuracy (resolution 0.1aV or 0.1m0)
500V non-blow meter, accuracy 10
accuracy not less than 2×1-1, resolution not less than 0.1uV, accuracy better than 1/53 of the filter tolerance
sub-calibration items and calibration methods | |tt||7.1 Calibration items 1
JJF1098—2003
Before the whole system is put into operation, the city shall calibrate the equipped instruments, meters, zero-voltage devices and industrial wiring used in the system and other components according to the corresponding requirements or standards. The results shall comply with the relevant requirements of 51.2 and the calibration certificate shall be traceable to the effective basic standard. The whole system shall be calibrated. The recommended calibration items are as follows: Table 3 Calibration items||tt ||Calibration items
Safety performance check
Scanning related potential
Channel effect selection
Photography
Measurement data processing and temperature test
Calibration station result uncertainty verification
Standard foreign system
Working system
T. Industrial system
Note: "one" in this text is a calibration item, "one" can not be postponed, the family must keep the data for a month to use 7.2 Calibration method
7.2.1 Report before calibration
Calibration Before installation, the system should be checked for valid calibration or quarantine certificates from various departments and meet the requirements of Article 1.1. The system should be configured according to the requirements of the operation and maintenance instructions to ensure that it is in a normal state. During the inspection, the system should not be rebuilt or repaired. 7.2.2 Safety performance inspection Use 500V megohms to measure the insulation of the power supply box after the system is installed and the signal input terminal. The system meets the requirements of 5.31: 3) Except for artificial settings that cause the system to freeze or be detected, the requirements of 5.3.2 are met. 7.2.3 Sweep the potential test of the switch parasitic point potential using a single-core residual conductor with a diameter of 1:6! After the sweep block is connected to the same wire at the output end, it is connected to the nanovolt meter. After 2m, cut off the eight points of the average output end of the plate: small, turn off the switch in turn, leave 60~60 in each position, record the maximum potential of the absolute value; scan the switch off for min, repeat 1 measurement: if the comparison point is repeated 3 times, the three times measured products of each channel are recorded as the life potential of the channel, and the specification is as follows: +
.2.4 Test the difference between the channel data 1098—2HL3
The measurement of the value of the data is carried out by the method of (2-level standard signal source input and simulation test point: the standard system is at point (104.62), T is the system at the rate point, T is the system at point m, the method is:
a will hit the switch and connect the input and output ends with a 1mm single-core steel wire, and then the signal source will be connected:, and the optimal value will be taken from each point The sampling value of each channel is measured repeatedly for times, and the average value of each channel is written as the dynamic sampling value. The error is the data set difference between channels. The sequence of results is as shown in Table 1. 2.5 Uncertainty verification || tt || The accuracy result is uncertain. The special configuration of the system is used as the standard, and the sample in Table 2 is used for calibration. Accuracy points: standard thermocouple and working disk metal thermocouple (419 .527:), aluminum (66).35237:), steel (1084.62T) points: working with cheap gold high thermal conductivity can be at the entire Baidu point, the upper resistance system is at 0 o'clock: 100 o'clock near the work of its secretion is:
) will be controlled to the measured temperature point, when the table (temperature performance fee state is recognized, the measurement is carried out; b according to the verification method adopted by the system actual sensing, get the measured value of micro-calibration point 1; compare the measured value with the test bar on the card Compared with known values, the difference is not greater than + (the uncertainty of the measured value when P = 95%, the uncertainty of the sample certificate 1 when P = 95%), and should meet the requirements of Table 1.
1.2.6 Electrical test
Direct test system is equipped with standard instrument as standard instrument, Table 2 main sample as calibration, test point: standard oil system center point (184.62): industrial system can store the highest temperature point, the second industry limit The system is accurate to 100 points. The method is:
will control the temperature of the system to be tested:
! The system is put on the belt to run the measurement: each steel light sink, 1 for the system to correct the temperature drop 5 it accounts for, the industrial system temperature drop 5 light left call after the temperature rise, hold the wet film record number compensation:) the maximum difference between the three test results is the system after the event, the total result should be the price of the plan in Table 1: 2.? The temperature performance test includes special The temperature control kinetic energy test of the model parts can be carried out by the system with uncertainty: the pilot test: 1 adjustment system is not a point (! 462), the industry system is carried out at 10 o'clock. The method is:
) The system presets the temperature point:
6) The inspection is about the special point of the system, set the control pair, and the device is worth avoiding the temperature and tends to the given:) The system also records the constant performance of the system before 6mn and the temperature change rate during the test. , its formation complies with the provisions of ".8 The test software can record and save the measurement data of the special software, and the verification records and verification results can be displayed and printed before inspection. The analog signal input method can be used in the digital channel: its record and printing format should comply with the requirements of JJF1098-2003. The original measurement data can be displayed, recorded and printed, but cannot be collected. The measurement data processing verification is carried out according to 7.2.4 analog signal method, or at the same time as 7.2.5 calibration result uncertainty verification: the inspection points are the standard or working metal thermoelectric system at zinc (419.527), lead (660.323℃), and Xiang (1084.62℃) points: the working metal thermocouple system can be carried out near the whole point, and the industrial system can be carried out near the center point and 0℃ point. The calculated results shall comply with the requirements of the relevant verification procedures and, when compared with the confirmed manual calculation results, the difference shall comply with the determination in Table 1. 8 Expression of calibration results
A calibration certificate shall be issued for the calibrated system (see Appendix C) 9 Calibration time interval
The recalibration time of the system can be determined according to the actual usage. The longest interval between recalibration is more than 1 year, and a calibration certificate shall be issued upon recalibration. 6
Appendix A
120:03
JJFO98
Example of uncertainty assessment of measurement results of standard potential couple automatic measurement system Mathematical model
According to the regulations, the thermoelectric potential value of the tested couple at the graduation point is Enip,= Exnlp +Be( t)
Wherein: Ei is the thermoelectric potential of the test couple at the desired point (aluminum, aluminum, zinc), mV; Estandard F(p
is the thermal potential given by the standard instrument at the fixed point, mV; 2e(t) is the difference between the average value of the thermal potential of the test couple and the standard measured when the furnace temperature is t, mr[The formula can be written as
Ex=E+ente-es
Then (A-2) is the learning model A2 of this analysis. The variance and sensitivity coefficient
Totally differentiate the formula (A-2), and we get
dE( - dEstandard() + r - dea
The above formula is slightly modified and replaced by the uncertainty of the error source, then we get u3= uem + u., + m
Formula (A-3) is the variance formula for this analysis. (A—))
(A——3)
If all uncertainty components are calculated with microseconds, the coefficients of all sources of uncertainty are 1, that is, the coefficient of the calculation is c. =1. c =], c- -l.
43Calculate the standard technical uncertainty component (taking copper point as an example) 43. "E low-ton component is the uncertainty of the verification result of the value given in the standard instrument certificate at the fixed point. According to the verification system table, the expanded uncertainty of the first-class S-type couple at the definition point is 6.6, = 0.9, which belongs to the normal distribution. The inclusion factor is 2.58, 1l0.6=2.5y
B standard uncertainty entry. White deviation = ".A3,2R:n points| |tt||) The temperature of the furnace is! The source of the detected thermoelectric potential is the thermoelectric potential, which is the component of the uncertainty when measured by the electric measuring instrument. The system uses a digital scale of 2010, HP34420, etc. In the use range of 100mV, its measurement error is
37×10°×reading+9×10×range
The measurement error obeys the uniform distribution, that is,
d.575my×37×T0+TMIV×9×100.74V3
IJF 1098—2003
is the B prize, the relative uncertainty of this estimate is 10%, so the degree of freedom = 50, the influence of furnace temperature wrinkle effect
According to the design of the system, the control of furnace temperature, that is, the constant temperature characteristic index is 0.1%/rnin, and the error is held for more than 6 minutes. The automatic calibration system collects data quickly, and half of it can be measured within 4 minutes of forging. Taking the unidirectional change of furnace temperature as an extreme case, after collecting 4 numbers in each of the two cycles, the wet change is 0.4℃, then the standard and the last test may have an influence of 0.2 (that is, 0.2℃ is half the interval), and it is estimated according to the inverse sine rule, then /g/℃×0.2=1.56py
The relative uncertainty of this estimate The uncertainty is 50%, that is, the uncertainty = 2, belonging to Class B. The standard uncertainty component of the reference end temperature band is measured with 0 reference end. The actual reference end temperature deviation is estimated to be 0.2% to 0% according to the extreme, and the half interval is 0.1℃, that is, there is a 1V difference. According to the uniform distribution, there is 1
. The relative uncertainty of the calculation is 50%, so the uncertainty U2.3=2, R is divided into:) The parasitic thermal potential of the switching point is the partition of the measured data. The thermal potential of each contact is not more than 0.4V. It is calculated in half interval and evenly distributed, so 0.2=0.115gv
. The estimated relative uncertainty is 0%, that is, the uncertainty 2=5, the same as Class B.) Two re-tests should be done during the inspection, and the difference is not more than 4V. Take the average as the calibration result (reflecting the influence of the furnace field, half interval, average distribution, then there are 21.15ay
very reliable, vs=.
43.3 items, which include:) When the electric measuring instrument measures the standard, its thermoelectric potential value is assumed to be of the same order of magnitude as the calibrated instrument. Based on the analysis of the uncertainty of the measurement results of the electric measuring instrument, when the ambient temperature changes significantly in a short period of time, the previous items described in 3.2a) of this article are considered to be offset, and only the (9×× process) is left, as the nonlinearity that is different from the calibrated value. Its distribution, according to the function, is consistent with the 43.2a item, that is: lIxlm × 9× -k
Pg.t=21=50, belonging to Class B.
) The uncertainty caused by the uneven temperature field of the furnace has been included in the analysis of the calibrated instrument, and these sensitive areas are not important. The influence of the thermoelectric potential on the standard is the same as that of the tested electrode, so 1=+0.58
.:=2. The influence of the thermoelectric potential on the standard is also the same as that of the tested electrode, so
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