SIG for IEC 61499 (Distributed Systems)

The CAN in Automation (CiA) group has established the CANopen SIG (Special Interest Group) "IEC 61499". The group's scope is the development of a framework specification for CANopen-based systems using an IEC 61499 compliant programming environment. During the inauguration meeting the experts from Epis, Isagraph, NXP Control, and Weidmüller agreed to provide a very first proposal at the SPS/IPC/Drives exhibition in November. It is intended to support a migration path from IEC 61131 based decentralized control systems to distributed control systems using IEC 61499 function blocks.

A function block in the IEC 61499 standard is the basic building block from which entire applications may be built. There are two types of function blocks: basic function blocks and composite function blocks. A composite function block contains other composite function blocks and/or basic function blocks. A basic function block contains algorithms and an execution control chart (ECC). Each function block has event inputs and outputs as well as data inputs and outputs. In a basic function block the execution of an algorithm is triggered by the occurrence of an input event. The executed algorithm then from the input data produces new output data. When the algorithm has finished executing an output event is generated. This output event might then be the input event to another function block.
CANopen comprises the application layer protocol (EN 50325-4) and profile specifications defining a list of parameters (process and configuration data as well as diagnostic information). CANopen is based on the CAN (Controller Area Network) protocol, internationally standardized in the ISO 11898 series. CAN and CANopen are designed for distributed control systems.