계층제어구조에서 결합된 서브시스템의 비교분석

Comparison Analysis of Subsystem composited in Hierarchical Control Structure

In industrial control system used by Programmable Logic Controller(PLC), Ladder Diagram(LD) is the about widely utilized and plays an important role in industrial control system. But recently, the study about Sequential Function Chart(SFC) is performed actively. When we program by SFC, generally, we design one routine from start to end. This method is difficult to design, and we often make mistakes. In this paper, we propose the method that we compose each sub-system after we design each sub-system and we analysis the difference of the method used this paper from conventional method.