Function Block Applications for Process Control System BASED ON Fieldbus Technology

Present and future digital process control systems need to many requirements,for example,increase security and safety,reduce time to market, minimize training costs,support integrated methodology for implementation,and so on. Process control systems are required to fulfil these requirements in terms of their architecture and their operation during all the phases of the life cycle. The accepted basic concept for the design process control system is to describe all necessary implementation-specific functions with function block.IEC 61804 defines the function block for process control.In this paper, we discuss how a consistent function block capability may be provided for all fieldbus technology utilized in a control system. Examples will be given of how this standard has been applied in modern control systems to give a consistent interface to Foundation Fieldbus and PROFIBUS. Some detail will be presented on the standard means that is defined for manufacturers to describe function block capability of a field device.