Development Of Thermal Control System Performance Assessment Software Based On OPC Technology

With the development of the process automation, equipment manufacturers want to integrate different hardware and software products, thus, they can transfer the industrial field data from workshop level to the whole enterprise. It needs an open standard to access and management the data effectively, then we can communication between all the data sources, in this case, OPC technology emerged. On the other hand, if the control system has no regular maintenance, its performance will degenerate with the time go on, and a bad control performance will reduce the validity of the control system. So we developed the thermal control system performance assessment software based on OPC technology.OPC is an open interface which defined in Microsoft’s COM/DCOM technology, using the model of client/server. OPC server is the data provider, responsible to provide the data for the OPC clients. OPC client usually developed by the customer, they need not to concerned about the bottom of the hardware characteristics and how does the software and hardware communicate, it only need to follow the OPC data interface protocols, then we can gather the information from the OPC server. In this way, we can realize the system truly integrated.In this paper, we grasp the COM technology and OPC data access standard. We choose Visual C++as development tool and Microsoft access as database. The software has a few modules such as master control platform, access validation, data acquisition, system performance assessment, information inquiry. It can connect to variety of OPC servers for reading, writing, and mutual communication. Finally, we choose the Siemens s7-200PLC as hardware equipment, the PC as the client, and they can communicate.The system performance assessment software designed can be used in practical application, also it can realize accessing data of multiple devices in a unified way, and avoid the driver programming repeatability. This way can not only save money, but also protect the technology of hardware provider. I think the OPC technology will have a broad application prospect.