Rockwell Automation Logix5000 Controllers Sequential Function Charts Programming Manual - Manual (Page 5)

Table of contents
Studio 5000 environment...........................................................................................9
Additional resources.................................................................................................. 10
Chapter 1
Introduction................................................................................................................ 11
What is a sequential function chart?..................................................................... 12
Define the tasks .......................................................................................................... 14
Choose how to execute the SFC ............................................................................ 15
Define the steps of the process................................................................................ 16
Step guidelines..................................................................................................... 16
SFC_STEP structure......................................................................................... 17
Organize the steps...................................................................................................... 20
Sequence ............................................................................................................... 22
Selection branch ................................................................................................. 22
Simultaneous branch ......................................................................................... 23
Wire to a previous step ..................................................................................... 24
Add actions for each step ......................................................................................... 25
How do you want to use the action? ............................................................. 25
Use a non-Boolean action ................................................................................ 25
Use a Boolean action ......................................................................................... 26
SFC_ACTION structure ................................................................................ 27
Describe each action in pseudocode...................................................................... 28
Choose a qualifier for an action ............................................................................. 29
Define the transition conditions............................................................................ 30
Transition tag ...................................................................................................... 31
How do you want to program the transition? ............................................ 31
Use a BOOL expression ................................................................................... 32
Call a subroutine in a transition ..................................................................... 32
Transition after a specified time ............................................................................ 33
Turn off a device at the end of a step .................................................................... 35
Choose a last scan option ................................................................................. 36
Use the Don’t Scan option .............................................................................. 38
Use the programmatic reset option ............................................................... 38
Use the automatic reset option....................................................................... 40
Keep something on from step-to-step .................................................................. 42
How do you want to control the device? ..................................................... 42
Use a simultaneous branch .............................................................................. 42
Store and reset an action................................................................................... 43
Use one large step ............................................................................................... 44
Preface
Design a sequential function
chart
Rockwell Automation Publication 1756-PM006F-EN-P - October 2014 5