检定S型短型热电偶的4种不同冷端补偿方法之比较

摘要

When we test the testing - length during 200 ~ 700 mm S type thermocouple, the TR is based on the room temperature or fluctuant temperature. It should take to revise or to compensate to keep the TR in 0℃. We use the widely used four cold junction compensation methods to test the same S type thermocouple, and analyze results. The results proved that the method about "the reference end is to extend the like polarity thermocouple which can reach the first standard thermocouple class of accuracy to reference end thermostat" is the better compensation method.%检定长度在200 ～ 700 mm范围内的S型热电偶时,由于参考端温度大都处于室温或者波动的温场之中,需要将参考端温度恒定在0℃或采取修正、补偿等措施进行修正.现采取检定中最常用的4种不同的冷端补偿方法检定同一支S型短型热电偶,对结果进行比较分析,得到这4种不同的冷端补偿方法的优劣性及其准确度排序.结果表明,“将参考端应用达到一等标准热电偶准确度水平的同极性热电偶丝延伸至参考端恒温器”方法能获得较为理想的补偿效果.