Siemens SIMATIC PROFINET Function Manual page 5

Changes compared to previous version
This manual encompasses the following new functions compared to the previous version
(version 12/2014):
Function
PROFINET IO on the 2nd
PROFINET interface
IRT with very short data cycle
times down to 125 µs
MRPD: Media Redundancy
with Planned Duplication of
frames
PROFINET performance
upgrade
Limitation of the data infeed
into the network
Conventions
STEP 7: We refer to "STEP 7" in this documentation as a synonym for the configuration and
programming software "STEP 7 as of V12 (TIA Portal)" and subsequent versions.
This documentation contains pictures of the devices described. The figures may differ
slightly from the device supplied.
You should also pay particular attention to notes such as the one shown below:
Note
A note contains important information on the product, on handling of the product and on the
section of the documentation to which you should pay particular attention.
See also
PRODIS (http://www.siemens.com/simatic-tech-doku-portal)
Catalog (http://mall.industry.siemens.com)
PROFINET with STEP 7 V14
Function Manual, 09/2016, A5E03444486-AG
Applications
You can operate another
PROFINET IO system on the CPU or
connect additional IO devices.
You realize high-end applications with
IO communication which place very
high performance demands on the IO
processing.
PROFINET IO IRT enables you to
realize applications that place particu-
larly high demands on the reliability
and accuracy (isochronous mode).
You can implement applications with
high speed and send clock require-
ments. This is interesting for applica-
tions with high demands on
performance.
You limit the network load for standard
Ethernet communication to a maximum
value.
User benefits
You use a fieldbus type in the plant.
The CPU can perform fast and deterministic data
exchange as an I-device with a higher-level con-
troller (PROFINET/Ethernet) through the second
line.
You make PROFINET IO communication and
standard communication possible via one cable
even with a send clock of 125 µs.
By sending the cyclic IO data in both directions in
the ring, the communication to the IO devices is
maintained even when the ring is interrupted and
does not result in device failure even with fast
update times. You achieve higher reliability than
with MRP.
Better utilization of the bandwidth results in short
reaction times.
You flatten peaks in the data feed.
You share the remaining bandwidth based on
demand.
Preface
5