Glossary • 131
WAGO-I/O-SYSTEM 750
Busklemmen
Element
Functions, function blocks and programs are elements.
Each element consists of a declaration part and a body. The body is written
in one of the IEC programming languages IL, LL, FBD, ST, and FC.
EN 61131-3
European Standard containing the German translation of
IEC 1131-3
and
having the status of a German Standard.
End module (Termination module)
An end or termination module is needed for faultless operation of the node.
The end module is always placed as the last module in order to obtain a ter-
mination of the fieldbus node. This module has no I/O function.
F
Fieldbus
System for serial data transfer between devices of automatization in the
process field range.
Fieldbus node
(Short form: node)
A fieldbus node is a unit or a module equipped with a Neuron chip as a mi-
cro controller, possibly supplemented by an external memory and I/O func-
tion. The smallest addressing units are nodes.
Free
Topology
The Free Topology is a network topology, which was possible for the first
time with the
FTT-10 Transceiver
. In free topology it is possible to mix line,
star or ring structures together.
However, in this case the maximum transmission spacings are dependent
upon the cable quality. Due to the use of
Routers
or
Repeaters
the transmis-
sion spacing limits can be overcome.
Function
If the input values of a function are always identical , it returns always the
same result (as function value). A function has no local variables, which sto-
res values in excess of a request.