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Sequential function chart (SFC) is a graphical programming language used for programmable logic controllers (PLCs). It is one of the five languages defined by IEC 61131-3 standard. The SFC standard is defined as, Preparation of function charts for control systems, and was based on GRAFCET (itself based on binary Petri nets).
It can be used to program processes that can be split into steps.
Basic Batch SFC, with important elements labelled
Main components of SFC are:
Steps with associated actions;
Transitions with associated logic conditions;
Directed links between steps and transitions. ...