In this chapter, we explored SFCs and their typical uses within an automation project. We looked at the few core elements that make up an SFC and created a simple backwash process routine. The use of SFCs varies from industry to industry; however, there are certain cases where leveraging the IEC SFC construct can greatly simplify the creation and debugging of a program.
As with the previous IEC languages that we have covered in this book, selecting the appropriate language for your application is like selecting the correct tool to solve the problem you are facing. Although some programmers will only ever write in ladder logic, there are many advantages to using the full range of IEC languages where appropriate.
In the next chapter, we will identify ways to organize and control the scan frequency of a routine using tasks and programs.