Building a backwash SFC routine

In this section, we will demonstrate the use of an SFC by building a backwash process using a step-by-step guide. The backwash process will be run to flush out the filters used in our process once they become too dirty. Let's follow these steps to do so:

1. First, we will need to declare our new routine. Right-click on the MainProgram scope in the Controller Organizer pane and select New Routine:

2. In the New Routine form that appears, enter or select the following values:
   • Name: BACKWASH
   • Description: Backwash Sequence
   • Type: Sequential Function Chart

Then, click on OK:

3. In order for our newly created routine to be executed with each scan of the controller, we will need to add a reference to it in the MainRoutine program, which is executed with each scan of MainTask.
4. Double-click on our MainRoutine program...