SFC macro steps

A macro step is a special symbol that represents, within an SFCClosed "Sequential function chart" It can be used to program processes that can be split into steps. The main components of SFC are: - Steps with associated actions - Transitions with associated logic conditions - Directed links between steps and transitions chart, a part of the chart that begins with a step and ends with a step. The body of the macro-step must be declared in the same program. The body of a macro-step begins with a special "begin" step with no link before, and ends with a special "end" step with no link after. The symbol of the macros step in the main chart has double horizontal lines:

A: Main Chart
B: Body of the macro-step

1: Macro step symbol
2: "Begin" step
3: "End" step


    • The macro-step symbol and the beginning step must have the same number.
    • The body of the macro-step must have no link with other parts of the main diagram (must be connected).
    • A macro step is not a "sub program". It is just a drawing features that enables you to make clearer charts. You must never insert several macro-step symbols referring to the same macro-step body.