负温度系数热敏电阻温度计设计实验中的参数选择

Selection of Parameters in Design and Experiment of Negative Temperature Coefficient Thermistor Thermometer

利用非平衡电桥法设计热敏电阻温度计是很适合于培养学生创新能力的物理类设计性实验。本文从理论分析了电路中的参数对温度计的温度特性的影响,研究发现,当选择R1=R2,不仅电路简单,当其阻值选择热敏电阻所处的低温点阻值和高温点阻值的平均值附近时,在测温范围为20~80℃时,其电桥的输出电流与温度的线性较好,并利用实验对其进行了验证。

It is a physical design experiment suitable for innovative ability training to us unbalanced bridge method to design thermistor thermometer.The influence of circuit parameters on the temperature characteristics of thermometer is analyzed theoretically.It is found that the circuit is simple when R1=R2 is chosen.The linearity between the output current of the bridge and temperature is good in the temperature range of 20~80℃when the resistance value is near the average value of low temperature point resistance and high temperature point resistance,and it is verified by experiments.