Application of FF FFB in hybrid/batch control

A scheme employed, by means of the flexible function block (FFB), to solve the unsatisfactory control effect of foundation fieldbus (FF) on hybrid/batch control is proposed in this study. Two types of FFBs have been developed, one of which can be embedded into a FF instrument directly and is able to fully communicate with all other devices on the FF network. It is characterized by a complete distributed solution based on FF. And the other can integrate, as an interface, a programmable logic controller (PLC) into FF network to perform the required hybrid control. It is characterized by a centralized solution. Finally, application of the two types of FFBs in hybrid/batch control is explained by the case from the field demonstration of function block capability in hybrid/batch application (FBCiHBA) hosted by Fieldbus Foundation in USA. The successful application of these two types of FFBs in this case illustrates that the FFBs can meet the requirements of hybrid/batch control