Industrial thermometer heat return difference estimation

Of platinum resistance thermometer heat return difference and estimate the influence of thermal stress, need to be very careful test. If suspected of thermometer heat return difference, it has to be in the process of test of the thermal process control of the thermometer. Meaningful return difference test is in the whole temperature range for dividing the thermometer, and the dividing method is respectively according to the direction of temperature and cooling direction in many temperature points compared with standard platinum resistance thermometer. Test from beginning to end to use with a standard platinum resistance thermometer and the same resistance measuring instrument, it is very important for avoiding the effect of measuring instrument error. Both heating and cooling, to ensure that all the participants from a thermometer test temperature smoothly transition to another test temperature, so it can control the heat process, point to the same temperature of heating and cooling the average resistance value, is concluded that the average R a T curve, this experiment using interpolation is standard platinum resistance thermometer using interpolation, in - 196 ℃ to + 196 ℃ temperature range, general need four dividing point. Each test temperature resistance and the difference between the average resistance thermometer convert temperature. This test method for some problems in the practical work. If you use the liquid tank as a dividing device, so that every liquid has its limited temperature range, the range may narrow to 100 ℃. That is to say, in order to keep the thermal process of the thermometer is changeless, may want to try being a thermometer very quickly from a slot to another slot. The transfer process, but also can produce tiny will measure the resistance change, these changes are caused when operating mechanical shock. Using the above method in falling in to a number of different degrees of span thermometer element types for a wide range of test. From this test as well as to other different types of platinum resistance thermometer elements of test point of view, the size of the return difference is proportional to the temperature span, large span the midpoint of the difference in temperature. Also found that the heat return difference has a good reproducibility, temperature cycle the same way, the hysteresis is also the same. 估计的影响在铂热电阻温度计和热应力测试需要非常小心。 如果一个温度计被怀疑有一个返回的热量,温度计的加热过程必须控制在测试期间。 有意义的回归测试是温度计的校准在整个温度范围内通过比较它与标准铂电阻温度计在许多温度点气候变暖和变冷的方向,分别。 使用相同的标准铂电阻温度计和相同的电阻测量仪测试很重要,以避免测量误差的影响。 是否加热或冷却,它是必要的,以确保测试顺利的温度从一个测试温度转移到另一个,这样可以控制热过程和加热和冷却电阻的值在同一温度点可以平均平均R T曲线。 在这个实验中使用的插值是一样的使用标准电阻温度计。 温度范围从- 196°C + 196°C,四个分割点通常是必需的。 转换不同的电阻值的电阻温度测试点和平均价值温度计温度。 存在一些问题在这个测试方法的实际工作。 如果使用液体槽分隔装置,每个液体温度范围有限,这可能是狭窄的100°C。 这意味着温度计可以非常迅速地从一个位置移动到另一个为了维持温度计的热过程。 这个转移过程也会产生电阻小而可衡量的变化在操作过程中由于机械冲击。 广泛的实验进行了用上述方法在许多不同类型的温度计元素不同。 根据这个和其他测试不同类型的电阻温度计,反弹的大小正比于温度跨度,大差异发生在温度跨度的中点。 还发现,热回收错误具有良好的重现性,同样的温度循环模式和同样的磁滞回线。