Creating SFCs
7
7.1
Overview of Sequential Function Charts (SFCs)
Introduction
The SFC editor enables you to graphically configure and commission sequential control
systems. A sequential control system enables a status-driven or event-driven sequence of
production processes. The sequential control system controls the functions created with CFC
based on sequences and executes them selectively.
An SFC offers two independent versions of sequential control systems for different application
scenarios:
● SFC
● SFC type with SFC instances
SFC
An SFC is a standardized interface for controlling the SFC with the user program or by the
operator. The sequential control system accesses the blocks and signals directly and is
therefore not reusable.
SFC type/SFC instance
An SFC type is a standardized interface for controlling the SFC with the user program or by
the operator. You can extend the interface. The SFC type accesses only its own interface and
can therefore be used as often as required as an SFC instance.
Sequencer
Sequencers enable status-dependent and event-driven execution in the SFC. The sequencers
of an SFC can be controlled through start conditions defined in various ways, such as:
● An SFC can include up to 8 sequencers.
● An SFC type can include up to 32 sequencers.
You can find additional information in the SFC documentation.
PCS 7 SMART Getting Started - Part 1 (V9.0 with APL)
Getting Started, 12/2017, A5E42181435-AA
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