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2. Logical equation of a step
Here we show the basic principles for establishing the logical equations of GRAFCET steps and associated actions, introducing on/off modes.
2.1 Reminder of evolution rules
The syntax of GRAFCET is the subject of a standard (NF C03-190) and is based on five evolution rules that define the active or inactive character of a GRAFCET step.
Rule 1: Initial situation
Initialization specifies the active steps at the start of operation. They are activated unconditionally and marked on the GRAFCET by doubling the sides of the corresponding symbols.
Rule 2: crossing a transition
A transition is either enabled or disabled. It is enabled...
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Logical equation of a step
Bibliography
Works
Websites
AFCET GRAFCET group
http://www.gsip.cran.u-nancy.fr/GRAFCET/groupe/groupe_old.html
EEA Club GRAFCET group
http://japura.lurpa.ens-cachan.fr/grafcet/generalites/groupe_fr.html
...Standards
- Schematics, diagrams, tables – GRAFCET function diagram for describing control logic systems - NF C03-190 - 9-1995
- Documentation and graphic symbols – Functional diagrams for control systems – GRAFCET" function diagram – Extensions of basic concepts - UTE C03-191 - 6-1993
- Établissement de diagrammes fonctionnels pour systèmes de commande - IEC 60848 - 12-1988
- Langage de spécification GRAFCET pour diagrammes...
Organizations
WADAF
French Association for Economic and Technical Cybernetics (AFCET)
Manufacturers, constructors
non-exhaustive list
Merlin Gérin, Télémécanique
Siemens
Omron
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