Introduced a method of the thermocouple instrument calibration. Using of Labview and high precision analog output card, the computer can translate the temperature difference into the 0 ~5V DC voltage output, and form the function relation from a variety of types of thermocouple degree, which is used to modify non-strict linear function of thermocouple EMF and temperature difference. Then the outside analog circuit translate the 0 ~ 5V voltage into the EMF. This method can achieve the thermocouple instrument calibration for a variety of types of thermocouple and range of temperature. According to data test and analysis, all errors of output EMF are acceptable, the method is easy operated and can be used for thermocouple instrument calibration.%提出了一种热电偶测量仪表的校准方法.采用Labview软件和高精度模拟输出板卡相结合的方法,将温差转化为0～5V的直流电压输出,将不同类型的热电偶分度表拟合出函数关系,用于纠正热电偶产生的热电动势和温差之间非严格线性关系,然后通过外部模拟运算电路将板卡输出电压转化为标准热电偶的温差电动势输出,可以实现多种类型热电偶测量仪表在不同使用温度范围的校准.经过数据测试及分析,输出的温差电动势均在允许的误差范围内,且操作简便,能很方便地用于热电偶测量仪表的校准.
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