Design A Sequential Function Chart; Introduction - Allen-Bradley Logix 5000 Programming Manual

Introduction

Design a sequential function chart

A sequential function chart (SFC) is similar to a flowchart of your process. It
defines the steps or states through which your system progresses. It helps you do
the following:
•
Organize the functional specification for your system.
•
Program and control your system as a series of steps and transitions.
By using an SFC to specify your process, you gain these advantages.
•
Since an SFC is a graphical representation of your process, it is easier to
organize and read than a textual version.
•
Add notes that clarify steps or capture important information for use
later on.
•
Print the SFC to share the information with other individuals.
•
Since Logix 5000 controllers support SFCs, you do not have to enter the
specification a second time. You are programming your system as you
specify it.
By using an SFC to program your process, you gain these advantages.
•
Graphical division of processes into its major logic pieces (steps)
•
Faster repeated execution of individual pieces of your logic
•
Simpler screen display
•
Reduced time to design and debug your program
•
Faster and easier troubleshooting
•
Direct access to the point in the logic where a machine faulted
•
Easy updates and enhancements
Rockwell Automation Publication 1756-PM006I-EN-P - February 2018
Chapter 1
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