SIEMENS
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Siemens D 21.4 · 2017
Communication
PROFINET
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Overview
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Flexibility
Short response times and optimized processes are the basic
requirements for competitiveness in global markets because the
product lifecycles are increasingly becoming shorter.
PROFINET ensures maximum flexibility in plant structures and
production processes and enables innovative machine and
plant concepts to be implemented. For example, mobile devices
can also be integrated at locations that are difficult to access.
Flexible topologies
In addition to the linear structure characterized by the estab-
lished fieldbuses, PROFINET also enables the use of star, tree
and ring structures. This is made possible by the switching tech-
nology via active network components, such as Industrial Ether-
net switches and media converters, or by integrating switch
functionality into the field devices. This creates greater flexibility
for the planning of machines and plants, as well as reducing the
cabling requirements.
The PROFINET network can be installed without any specialist
knowledge at all and meets all requirements that are relevant in
the industrial environment. The "PROFINET Installations Guide-
lines" assist manufacturers and users with network planning,
installation and commissioning. Symmetrical copper cables or
RFI-resistant fiber-optic cables are used, depending on the
application. Devices from different manufacturers are easily
connected via standardized and rugged plug connectors (up
to IP65/IP67 degree of protection).
By integrating switch functionality into the devices, linear struc-
tures can be created that are directly oriented toward an existing
machine or plant structure. This reduces cabling overhead and
cuts down on components such as external switches.
IWLAN
PROFINET also supports wireless communication with Industrial
Wireless LAN, opening up new fields of application. For example,
technologies subject to wear, such as trailing cables, can be
replaced and the use of automated guided vehicle systems and
mobile operator terminals becomes possible.
Safety
The PROFIsafe safety profile, which has been tried and tested
with PROFIBUS and which permits the transmission of standard
and safety-related data on a single bus cable, can also be used
with PROFINET. No special network components are necessary
for fail-safe communication, which means that standard
switches and standard network transitions can continue to be
used without any restrictions. In addition, fail-safe communi-
cation is equally possible via Industrial Wireless LAN (IWLAN).
Open standard
PROFINET, the open multi-vendor standard
(IEC 61158/IEC 61784), is supported by PROFIBUS and
PROFINET International (PI). It stands for maximum transpar-
ency, open IT communication, network security and simultane-
ous real-time communication.
Thanks to its openness, PROFINET provides the basis for a
standardized automation network in the plant, to which all other
machines and devices can be connected. Even the integration
of existing plant components, for example with PROFIBUS,
presents no problems due to the use of network transitions.
Use of Web tools
Thanks to the unrestricted support of TCP/IP, PROFINET permits
the use of standard Web services in the device, such as Web
servers. Irrespective of the tool used, information from the auto-
mation level can be accessed from virtually any location using a
commercially available Internet browser. This considerably sim-
plifies commissioning and diagnostics. Users can then decide
for themselves how much openness to the IT world they want to
allow for their machine or plant. This means that PROFINET can
be used simply as an isolated plant network or connected via
appropriate security modules, such as the SCALANCE S mod-
ules, to the office network or the Internet. In this way, new remote
maintenance concepts or the high-speed exchange of produc-
tion data become possible.
Expandability
On the one hand, PROFINET facilitates the integration of existing
systems and networks without any great effort or expense. In this
way, PROFINET safeguards investments in existing plant com-
ponents that communicate via PROFIBUS and other fieldbuses
such as AS-Interface. On the other hand, additional PROFINET
nodes can be added at any time. By using additional network
components, network infrastructures can be expanded using
cabling or wireless methods – even while the plant is operating.
© Siemens AG 2017