我厂原设计电子电位差计外线路接线都是这样的:用补偿导线将每支热电偶冷端引到表屏端子上,然后用铜导线接入电位差计端子。这样的接线我们在使用中发现仪表指示的温度总是比热电偶热点温度高一些,高出的数值随室温的不同而异。经分析,引起测量误差的原因可能是由于表温与热偶延伸的冷点温度不同而产生。 I plant the original design of the electronic potentiometer outside the line wiring is this: the compensation wire leads each cold junction thermocouple table terminal, and then use copper wire access potentiometer terminal. Such wiring we found in the use of instrumentation indicates the temperature is always higher than the thermocouple hot spot temperature, the higher the value varies with room temperature varies. After analysis, the cause of measurement error may be due to the table temperature and thermocouple extension of the cold temperature caused by different.