The Design Of Dynamic Simulating Control System For Circulatign Water Based On S7-300

The shortage of water resources has been attracted special concern for a long time in the world, especially in the situation of advocating the establishment of energy conservation oriented society now.Circulating water plays an important role in industrial development,it can reduce the production cast,improve efficiency of production.and what is more,it can reduce water consumption in the large scale,saving resources and protecting the environment,and then Improve the comprehensive benefit of the factory.The tradition method of dosing and conventional instrument control has many shortages,such as difficult to control,control precision is not enough and so on.Therefore,this paper designs a system circulation water based on S7-300 PLC of SIEMENS company. It can control and manage single or multiple experiment device used to solve the the technical problems and adapt to the industrial development needs.In this paper, the design and implementation of S7-300 circulating water control system hast a detailed theoretical discussion and detailed description of the design.The entire system has friendly interface, easy to manage and monitor function. The lower machine control system can realize the control for some important parameters,such as temperature control, flow control and controlling respective valve means, pump.The upper computer includes security interface and a variety of monitor screen design, which can achieve permission to operate, flow picture, historical curve, generate reports, alarm screen and found a human-computer interaction, remote monitoring function. As follows the design has several features:first, the design of upper computer based on FIX configuration software,which has vivid images and it is more convenient for factory employees’applying; Secondly the lower computer can realize the real-time data acquisition and automatic control function which can processing system data and respond to equipment failure in time.in addition, Siemens S7-300 is widely used in small and medium enterprises, prices are moderate;Finally, as for the data communication from upper and lower computer, the MPI communication technology is used, which meets the technical requirements of the system, and also greatly reduce the design cost.Debugging results show that the control system based on the S7-300 realizes the communication between upper and lower computer. Overall operation of the device is stable and reliable, safe, accurate dosing, a good man-machine interface.