Glossary
Windows Automation Center, WinAC Slot Version 4.0
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Hardware Installation and Operating Manual, Edition 02/2006, A5E00273194-02
Ground:
The conducting earth whose electric potential can be set equal to zero at any point.
In the vicinity of grounding electrodes, the earth can have a potential different
tozero. The term “reference ground” is frequently used to describe
thesecircumstances.
Ground, to:
To ground means to connect an electrically conducting component to the
groundingelectrode (one or more conducting components which have a very good
contactwith the earth) across a grounding system.
Hardware:
Hardware is the name given to the complete physical and technical equipment ofan
automation system.
Hot restart:
All data areas (timers, counters, bit memory, data blocks) and their contents are
retained. The controller executes OB 101, reads in the process input image, and
then continues processing the user program at the location where it was last
stopped.
Index:
A numbered slot in the PC Station, or virtual rack that represents a PC-based
automation system. The controller occupies one index. Other components can
occupy other index slots.
Industrial Ethernet:
Physical communications layer that supports communication to STEP 7, S7
CPUs,PGs, OPs, and S7 applications.
Interface, multipoint: -> MPI
Interrupt:
Interrupt is the name given to the interruption of program scanning in the
processorby an externally queued event – for example, timer expired, data request,
etc.
Isolated:
On isolated input/output modules, the reference potentials of the control and load
circuits are galvanically isolated, e.g., by optical coupler, relay contact, or
transformer. Input/output circuits can be connected to common potential.
