Access to process data with OPC-DA using IEC61499 Service Interface Function Blocks

The need for flexibility in manufacturing systems is continuously growing. This need deals with the establishment of design methodologies for implementing distributed applications. The IEC61499 define a generic architecture for designing distributed applications, based on Functions Block (FB) networks. The interface between the control software and the hardware is achieved by means of the so called Service Interface FB. But guidelines to implement this type of FBs are provided neither by the standard nor by the available tools. On the other hand, one of the most widely used industrial communication standard is OPC that enables the exchange of data between multi-vendor devices and control applications without any proprietary restrictions. Thus, an easy integration of this communication standard within IEC61499 applications may contribute to consolidate such standard. This paper presents the guidelines to use OPC in industrial applications through the definition an implementation of SIFBs to access process data using OPC-DA (OPC Data Access) specification.