福建省地方计量技术规范

福建省地方计量技术规范JJF（闽）1026－2009热工仪表校验仪校准规范CalibrationSpecificationforTemperatureCalibrator2009－11－01发布2009－11－01实施福建省质量技术监督局发布JJF（闽）1026－2009１热工仪表校验仪校准规范CalibrationSpecificationforTemperatureCalibrator本规范经福建省质量技术监督局于2009年11月01日批准，并自2009年11月01日起施行。归口单位：福建省质量技术监督局起草单位：福建省计量科学技术研究所本规范由起草单位负责解释JJF（闽）1026－2009JJF（闽）1026－2009２本规范主要起草人：肖红（福建省计量科学技术研究所）杨志斌（福建省计量科学技术研究所）参加起草人：林生（福建省计量科学技术研究所）陈欣（福建省计量科学技术研究所）王在旗（厦门市计量测试所）JJF（闽）1026－2009I目录1范围········································································（1）2引用文献········································································（1）3概述·············································································（1）4计量特性·······································································（1）4.1通用技术要求································································（1）4.2允许误差····························································（1）4.3分辨力····································································（2）4.4稳定性····································································（2）4.5绝缘电阻····································································（2）4.6绝缘强度····································································（2）5校准条件······································································（2）5.1校准环境要求····················································（3）5．2标准器及配套设备·····················································（3）6校准项目和校准方法······················································（3）6.1通用技术要求的检查···························································（3）6.2示值误差的校准····························································（4）6.2.1通电预热····································································（4）6.2.2校准点的选择································································（4）6.2.3测量功能各档示值误差的校准··················································（4）6.2.4输出功能各档示值误差的校准··················································（6）6.3冷端外部温度补偿器示值误差····················································（10）6.4分辨力试验·····································································（10）6.5稳定性试验·····································································（10）6.6绝缘电阻的校准·································································（10）6.7绝缘强度的校准·································································（10）JJF（闽）1026－2009II7校准结果表达···································································（11）8复校时间间隔···································································（11）附录A校验仪校准结果的不确定度评定···············································（12）JJF（闽）1026－20091热工仪表校验仪校准规范1范围本规范适用于准确度0.02级及以下热工仪表校验仪、工业过程仪表校验仪及具有相同使用功能的电子仪器(以下简称校验仪)的计量性能的校准。准确度高于0.02级校验仪也可参照本规范进行校准。2引用文献JJF1059-1999测量不确定度评定与表示JJF1071-2000国家计量校准规范编写规则GB/T16839.1-1997热电偶第一部分：分度表JB/T8622-1997工业铂热电阻技术条件及分度表JB/T8623-1997工业铜热电阻技术条件及分度表使用本规范时，应注意使用上述引用文献的现行有效版本。3概述校验仪是一种能检定或校准温度仪表、工业过程仪表及测量热电偶和热电阻信号的多用途电子设备。它一般包括输出功能和测量功能两部分。输出功能部分可输出直流电参量(包括直流电压、直流电流、直流电阻)以及各种分度号的热电偶和热电阻的模拟信号；测量功能部分可直接测量直流电参量(包括直流电压、直流电流、直流电阻)以及热电偶和热电阻、温度变送器或其它传感器、变送器的输出。4计量特性4.1通用技术要求4.1.1校验仪应具有设备名称、型号、仪器编号，生产厂家等信息。4.1.2校验仪附件、连接导线、电源线等应齐全。按键功能正常引线接插件必须接触良好。4.1.3校验仪的显示功能应标识明确，数字和符号清晰完整，不引起误读。4.2允许误差校验仪各参数最大允许误差（典型值）见表1，也可按产品的明示技术指标或产品说JJF（闽）1026－20092明书。表1校验仪各参数示值的最大允许误差输出功能测量功能直流电压mV档±(0.02%RD+5μV)±(0.02%RD+5μV)V档±(0.02%RD+0.5mV)±(0.02%RD+0.5mV)直流电流±(0.02%RD+1.5μA)±(0.02%RD+1.5μA)直流电阻±(0.04%RD)或±30mΩ(取二者的大值)4线制:±(0.03%RD+4mΩ)3线制:±(0.03%RD+15mΩ)热电势±(0.02%热电势+4μV)±(0.02%热电势+4μV)热电阻±0.3℃±0.3℃冷端温度补偿±0.3℃4.3分辨力校验仪各功能量程的实际分辨力应小于1.3d(d为该功能量程的显示分辨力)。4.4稳定性校验仪在校准环境条件下，各功能量程1h内的短期稳定性应优于最大允许误差的1/5。4.5绝缘电阻在环境温度为15℃～35℃，相对湿度为45%～75%时，校验仪的输入、输出、电源和接地（外壳）端子相互之间的绝缘电阻应不小于50MΩ。4.6绝缘强度在环境温度为15℃～35℃，相对湿度为45%～75%时，校验仪输入、输出、电源和接地（外壳）端子相互之间施加表2所规定的频率为50Hz的试验电压，历时1min应无击穿和飞弧现象。表2试验电压校验仪端子标称电压/V试验电压/V0U6050060≤U1301000130≤U25015005校准条件功能最大允许误差参数JJF（闽）1026－200935.1校准环境条件环境温度：（23±2）℃，环境相对湿度：（45～75）%，校验仪周围除地磁场外，应无影响其正常工作的外磁场。电源电压变化不超过额定电压的±2%，电源频率变化不超过额定频率的±1Hz。5.2标准器及配套设备5.2.1标准仪器及配套设备的选择应满足标准仪器及配套设备引入的扩展不确定度（k=2）小于校验仪对应功能的最大允许误差绝对值的1/3。表3列出在校准校验仪各参数最大允许误差（典型值）（见表1）时相对应的标准仪器及配套设备供参考选择（必要时，应考虑标准仪器及配套设备量值的修正值，以减小标准仪器及配套设备引入的测量不确定度）。表3校准用标准仪器及配套设备校准校验仪测量功能用标准器校准校验仪输出功能用标准器直流电压直流低电势电位差计不低于0.005级的直流标准电压源不低于允差为±0.005%的数字多用表或校准仪直流电流不低于0.005级标准直流电流源直流电阻、热电阻0.01级直流电阻箱热电势直流低电势电位差计不低于0.005级的直流标准电压源0℃恒温器(温度偏差不超过±0.05℃)或冰点槽；补偿导线（具有20℃修正值）冷端外部补偿二等标准铂电阻温度计或二等标准水银温度计恒温槽(工作区域温差不超过±0.05℃)绝缘电阻绝缘电阻表：直流电压500V，10级绝缘强度耐电压试验仪5.2.2分辨力校准时，所用标准仪器的分辨力应小于被校校验仪分辨力的1/5。5.2.3稳定性校准时，所用标准仪器的稳定性应高于被校校验仪稳定性5倍。6校准项目和校准方法6.1通用技术要求的检查功能测量设备校准项目JJF（闽）1026－20094用目视和手动检查。6.2示值误差的校准6.2.1通电预热接通电源，按说明书要求的预热时间(未说明的按30min)预热后进行校准。6.2.2校准点的选择校准点应按校准量程均匀分布，一般应包括上限值、下限值在内不少于6个点。6.2.3测量功能各档示值误差的校准6.2.3.1校准校验仪测量直流电压、测量直流电流和测量直流电阻的示值误差连接导线图1：校准测量直流电压的连接连接导线图2：校准测量直流电流的连接连接导线(a)二线制连接导线（b）三线制连接导线（c）四线制图3：校准测量直流电阻的连接被校校验仪直流电压源被校校验仪直流电阻箱被校校验仪直流电阻箱被校校验仪直流电阻箱被校校验仪标准电阻数字多用表(DCV档)直流电流源JJF（闽）1026－20095测量直流电压按图1，测量直流电流按图2、测量直流电阻根据不同线制按图3(a)(b)(c)所示将被校准的校验仪与标准器之间用导线连接，选择校验仪的功能和量程，按预先选定的校准点调节标准器的输出，观察校验仪的读数，等读数稳定后记下标准器的输出值和校验仪的读数值，则校验仪测量直流电压、测量直流电阻的示值误差按下式计算。Δa=Ax-An(1)式中：Δa——校验仪测量直流电压或测量直流电阻的示值误差