Glossary · Safety standards
IEC 60848
Also known as: GRAFCET
German: IEC 60848
IEC 60848 is the international standard that defines GRAFCET, a graphical specification language for describing the sequential behavior of control systems with steps, transitions, actions and receptivities, independent of the implementation technology.
- Standards
In one sentence
IEC 60848 defines GRAFCET, a graphical language for specifying the sequential behavior of control systems with steps and transitions.
Example
The specification of a drilling station describes its cycle as a GRAFCET according to IEC 60848, which the programmer then implements in SFC.
How it applies
- Engineering: GRAFCET is used to specify sequences in a technology-neutral way, especially in German- and French-speaking engineering and training.
- Implementation: The specification is often implemented as Sequential function chart (SFC) according to IEC 61131-3, but GRAFCET itself is a specification language, not a programming language.
- Documentation: GRAFCET diagrams are useful in functional specifications and training documents; the documentation team should use the notation consistently and state which standard version applies.
- Training: GRAFCET is widely taught in vocational and engineering education, so it is a familiar notation for many technicians reading specifications.
GRAFCET (IEC 60848) vs. SFC (IEC 61131-3)
GRAFCET specifies behavior; SFC is a programming language in IEC 61131-3 that implements it. They look similar but have different semantics and rules.