电阻温度计的检定-基础附录3

电阻温度计的检定一般的检定步骤StartNewRecord／开始新的记录VisualInspection／视觉检查Clean?,bent?／干净？弯曲？GenericChecks／普通检查Insulationresistance,Self-heating&Immersionassessments绝缘电阻，自热和浸入深度的估计ConditioningandAdjustment／处理和调整Annealing&Stabilitytests／退火和稳定性测试Comparison／比较SPRTsandverybestpartiallysupportedPRTs–FixedPointsSPRT和非常好的部分支撑的PRT－固定点PrecisionPRTs–Comparisoninbaths精密PRT－在恒温槽中使用比较法IndustrialPRTs–ComparisoninDry-Wells工业PRT－在干井炉中使用比较法Analysis／分析CalculationofcoefficientsorRvs.Ttable／系数的计算或生成分度表Uncertainties／不确定度Referencethermometer,heatsourcestability&uniformity,probespecificerrors参考温度计，热源稳定性和均匀性，探头特有误差CompleteRecords／完整的记录CalibratingPRTs／检定PRTCharacterization／标定Thermometerresistanceismeasuredatseveraltemperaturepointsandthedataisfittedtoamathematicalformula(mathematicalmodel).在几个点测量温度计的电阻，通过这些数据得到数学公式（数学模型）ToleranceTesting／误差测试Thermometerresistanceismeasuredatseveraltemperaturepointsandthedataiscomparedtodefinedvaluesatthosetemperatures.Nofittingisperformed.在几个点测量温度计的电阻，数据与相应的温度点的定义值比较。CharacterizationorToleranceTesting?／标定或误差测量Characterization／标定MostcommonforprecisionPRTs,providesbestuncertainty对精密PRT是最常用的方法，具有最好的不确定度Resultisuniquetoprobe,requiresuniquecompensationorlinearizationinreadouttotakefulladvantageofcalibrationdata结果只对单独的探头，需要在测温仪进行单独的补偿或线性化以充分利用检定数据Requireatleast5datapointsandsubstantialmathematicsforreasonableresults需要至少5个点的数据和数学计算以获得合理的结果ToleranceTesting／误差测量MostcommonforindustrialgradesofPRTs,onlyprovidesforstandardizeduncertainty对工业级PRT最常用的方法。只提供已经标准化的不确定度Resultclassifiesprobeintoanaccuracygrade,allowingnon-probespecificcompensationtobeused结果按准确度等级分类，允许使用补偿Canbecompletedwithafewas1or2datapoints使用1或2个数据即可完成。ExampleConfiguration／配置举例PrecisionThermometerReadout/DMMMethod精密测温仪／万用表方法ReferenceProbeDigitalMultimeterProbesUnderTestExampleDataSet／测试数据举例4个点＋水三相点温度测量值CalculateCoefficientsusingITS-90DeviationFunctions

使用ITS－90温标偏差函数计算系数Setofequations／等式Solvingforaandbusingexampledata:／求解方程 a=-5.3581671E-04 b=2.0307049E-05CheckCurveFitUsingITS-90InverseFunctions／使用ITS－90逆函数验证使用ITS－90逆函数计算残差Procedures-ToleranceTesting

步骤－误差测量Typicalapproachformediumtolowaccuracyandindustrialapplications主要应用于中等或低准确度的工业应用ResistanceattemperatureTiscomparedtodefined(table)values在温度T时的电阻与分度表的值比较InternationallyDIN43760,IEC-751,orASTM1137standardsanddefinedlimitsoferrorarecommon国际上常用的DIN43760,IEC-751,或ASTM1137标准PRT分类误差ExampleofLimitsoferrorusingIECTolerances／使用IEC允差的例子IEC751classA／IEC751A类=±[0.13+0.0017|t|]°C @100°C=[0.13+0.0017|100|]=±0.30°CIEC751classB／IEC751B类=±[0.25+0.0042|t|]°C @100°C=[0.25+0.0042|100|]=±0.67°C工业允差测试的例子Basicsystem／基本系统Fluke-744DocumentingProcessCalibrator／福禄克744校准器HartFieldDry-Well／哈特现场干井炉9103for-25℃to140℃(9103干井炉）9141for50℃to650℃（9141干井炉）Hart5614SecondaryReferencePRT哈特5614二等标准温度计Approximatesystemuncertainty±0.34°C(rssmethod)／近似的系统不确定度±0.34℃744PRTmeasurementaccuracy±0.3°C744测量PRT准确度为±0.3°C9141combinedstabilityanduniformity9141的稳定性及均匀性综合指标±0.16°@420°C5614PRT±0.023°C精密PRT的系统举例BasicSystem／基本系统1529CHUB-E4Readout／1529测温仪5626SecondarySPRT／5626二等标准DeepImmersionCompactBath／深井台式槽9938MET/TEMPIISoftware／9938软件Approximateuncertainty±0.03°C近似不确定度±0.03°C1529CHUB±0.012°C@200°C5626SPRT±0.009°C@420°C6331combinedstabilityanduniformity6331稳定性和均匀性综合指标±0.03°C@300°C标准温度计系统举例Basicequipment／基本系统1590SuperThermometer／超级电阻测温仪5681QuartzSPRT／石英护管一等标准温度计9114Freeze-PointFurnace／固定点炉590XFixedPointCells／固定点容器9938MET/TEMPIISoftware／软件Approximateuncertainty±3mKto±5mK近似不确定度±3mKto±5mK1590±1.5mK5681SPRT±1mK5906ZincPoint±1mKConclusion/结论PRTsaretrulyremarkableinstrumentsPRT是非常实用的仪器Withpropercareandattentiontodetailtheycanoperateover