Design And Realization Of Virtual Instrument-based Data Acquisition Card

The slag detection system is one of the most advanced technologies adopted in the modern continuous casting product line for steel quality. It includes a detection instrument with high gain and good anti-interference and a sensor working at about 1400癈. For improving the performance of the system, an idea based on the principles of a virtual instrument and its object-oriented design methods is proposed and realized by means of a personal computer with a DAQ (Data Acquisition Board) and their interface circuit. The idea is just that the development of a software system, a virtual data recorder, using Visual C++ 6.0 under Windows environment. The slag detection system and the PC with such a software system are combined to make a more powerful one, which can implement the real-time data processing functions in continuous casting product, including the display of the real-time slag signal, the storage of the data obtained in the process of the product, the inquiry of the bypast signal data and their printout. The new system has been tested on the continuous caster with lOOt ladles and the prospective results obtained.The industrial background and the slag detection in steel-making and the general idea of the virtual instruments are introduced firstly in this paper. And then the block diagram of the hardware system and its realization are given. It is more important that the software design must make the functions of the hardware system realized, which will be introduced in the Chapter 4 and 5 in detail, including its key technologies, the function modules and their operation flow charts. As a result, the typical curves recorded in on-line tests are given and some existing problems pointed for its further improvement as well hi the Summery chapter.