3 Fundamentals of press design

Press control systems
Fig. 3.5.5 PLC European manufacturer
3.5.7 Architecture and hardware configuration
The control system is divided into modules according to functional
groupings. This applies to the circuit diagram, the arrangement of the
switch cabinet and structure of the PLC software. The functional modules
do not necessarily correspond to the mechanical structural units –
in some cases similar functions such as all emergency stop circuits, all
protective grilles and the lubrication are grouped together.
Criteria used to determine the control structure include the logical and
functional coherence between different system elements and the minimization
of interfaces between the individual groups of functions. A well
designed architecture of the control system enhances clarity and transparency
of the electrical documentation and thus reduces the time spent
in design and start-up as well as in troubleshoooting during production.
3.5.8 Architecture of the PLC software
The PLC software is designed to correspond to the functional groupings
of the circuit diagram. Functional sequences, in particular those used
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