PT100水温测试系统的设计

The Design of Water Temperature Measuring System Based on PT100

考虑到水产养殖业中水温对溶氧度的影响,为确保水生物得予存活,打氧机又可节能工作,设计以STC12C5410AD单片机为主控核心,PT100为检测元件的水温测试系统.在此系统中,依据PT100在不同温度下具有不同阻值的特性,采用OP37运放设计了PT100电阻转换为电压的信号处理电路,并让单片机采集PT100转换输出的电压信号并对此信号进行数据处理.借助于RS232通信协议,将最终测试出的水温显示在上位机VB界面上.实验表明:所设计的系统能实时测试水的温度,测试误差在1℃的允许范围内,这为不同水温下不同溶氧量的调节提供了前提保障.

In view of effect of water temperature on dissolved oxygen concentration, the water temperature measuring system is designed with PT100 as the measuring sensor and single-chip microcomputer as the controlling core of system in order to make microorganism exist and oxygen machine work with energy saving. In this system, according to the PT100 characteristic of different resistance with different temperature, OP37 was adopted to design the signal processing circuit of converting resistance of PT100 into corresponding electronic voltage signal with different temperature. Then the single-chip microcomputer collected the converting signal and processed the data. By means of RS232 communica- tion agreement, the data processed by sing-chip microcomputer was transmitted to upper computer and the correspond- ing data of temperature was displayed on interface of VB. The system can measure real-time water temperature, further- more, the measuring tolerance is within I^C. By doing this, it can provide premise guidance for moderating different dis- solved oxygen concentration with different temperature.