In this chapter, we will implement a Sequential Function Chart (SFC) routine and break down the steps, actions, transitions, and branches that are used to construct it. We will also work with the online editing capabilities of SFC routines. Just as we have seen with the other IEC languages, SFC shares many of the common elements of other languages, but allows us to structure our programs in a different way. SFC programs are very well suited to running batches and cycles that follow a sequential step process or decision tree.
In this chapter, we will cover the following topics:
- Introducing SFCs
- Applying SFCs
- Using the SFC editor
- Building a backwash SFC routine
We will start this chapter with an overview of SFCs and their typical use within an industrial control system solution.