Research On Detect And Control System Of Surface Treatment Liquid In PS Plate Product Line Based On PLC

Concentration and temperature of the surface treatment liquid are the extremely important craft parameters in PS plate manufacture process. The effect of surface treatment and the quality of final production are directly determined by them. This topic conducts the research aims at the automatic detect and control system realization plan of the surface treatment liquid, in order to change the domestic situation that manual control and low-level automation control are used abroad at present, and build the solid foundation for comprehensive of data and automated advancement in production process.The research and development of the system based on PLC, involves the detection and control of many kinds of surface treatment liquid in multi-working processes, such as lye-degrease, electrolyte, decontamination, oxidation and so on. This thesis mainly aims at the lye-degrease section to conduct the research on designing the automatic detect and control system of concentration, temperature and liquid-level.In this thesis, SIMENS S7-200 series PLC CPU226 is selected as the computer on the spot, and PC as the center-monitor computer, the software package of STEP7-Micro/WIN32 is used for programming. At the same time, the King View software is chosen as the Human Machine Interface (HMI), by which users can monitor the real-time data and curves of conductivity, proportion and temperature; the condition of the scene pumps , valves and the level of liquid; the control parameters can be set and control mode can be transformed online, etc. In this system, district control strategy and PID control algorithm are used , the rule of control is clear about, and the program is easy to realize and expand. Through the on-line PID parameter experiments , good control effect can be obtained.This research obtains the CAPT scientific research item funds sustentation.