高精度恒温水浴控制系统的设计

Design on High-precision Constant Temperature Control System of Water-bath

水浴温度的精确控制是实现温度测量仪器正常工作的关键。系统针对金陵科技学院图书馆的干挂石材幕墙的热工性能测试中使用的PT100热电阻的温度检测校准要求,基于PID控制理论,以三菱PLC FX3U-32MT为控制器,使用触摸屏、电机搅拌电路、加热电路、供水电路实现水浴的智能高精度恒温控制。并在监控界面中设置了三级密码权限管理,保证了系统的安全可靠。实验测试结果表明系统的控制精度高,过调量小,工作稳定可靠。

The accurate control of water-bath temperature is the key technology to realize the normal work of temperature measuring instruments.This system aims at the calibration requirement for temperature measurement of PT100 thermal resistance used in temperature measurement of dry-hanging stone curtain wall in the library of Jinling Institute of Technology Library.It uses PLC FX3U-32MT of Mitsubishi as the controller based on PID control theory,and that uses touch screen,motor stirring circuit,heating circuit and water supply circuit to realize intelligent high-precision constant temperature control of water-bath.This system sets three-level password authority management in the monitor interface to ensure the safety and reliability.The experimental results show that the system has high control accuracy,small overshoot,and stable and reliable operation.