Siemens SIMATIC S7-1500 Manual page 27

Product overview
2.4 Firmware functions of the CPU
PROFINET IO
Function
RT (Real-Time)
IRT (Isochronous
Real-Time)
Isochronous mode
MRP (Media Redun-
dancy Protocol)
MRPD (Media Redun-
dancy with Planned
Duplication)
Shared device
26
RT prioritizes PROFINET IO telegrams over standard telegrams.
This ensures the required determinism in the automation technolo-
gy. In this process the data is transferred via prioritized Ethernet
telegrams.
A reserved bandwidth within the send clock is available for IRT
data. The reserved bandwidth ensures that the IRT data can be
transmitted in time-synchronized intervals, unaffected by other high
network loading (e.g. TCP/IP communication or additional real time
communication). Update times with maximum determinism can be
realized through IRT. Isochronous applications are possible with
IRT.
With isochronous mode, measured values and process data are
acquired and processed in a fixed system clock. Isochronous mode
thus contributes to high control quality and hence to greater manu-
facturing precision. Isochronous mode reduces possible fluctuations
of the process response times to a minimum. Time-assured pro-
cessing makes higher machine cycles possible.
With SIMATIC Drive Controller, the clock pulse systems of
SINAMICS Integrated, PROFINET (X150) and the technology I/Os
(X142) can be coupled together isochronously.
It is possible to establish redundant networks via the Media Redun-
dancy Protocol. Redundant transmission links (ring topology) en-
sure that an alternative communication path is made available if a
transmission link fails. The PROFINET devices that are part of this
redundant network form an MRP domain.
RT operation is possible with the use of MRP.
The advantage of the MRP extension MRPD is that, in the event of
a failure of a device or a line in the ring, all other devices continue
to be supplied with IO data without interruption and with short up-
date times.
MRPD is based on IRT and MRP. To realize media redundancy
with short update times, the PROFINET devices participating in the
ring send their data in both directions. The devices receive this data
at both ring ports. This eliminates the reconfiguration time of the
ring.
The "Shared device" function allows you to divide the modules or
submodules of an IO device up among different IO controllers.
Numerous IO controllers are often used in larger or widely distribut-
ed systems. Without the "Shared device" function, each I/O module
of an IO device is assigned to the same IO controller. If sensors that
are physically close to each other must provide data to different IO
controllers, several IO devices are required. The "Shared device"
function allows the modules or submodules of an IO device to be
divided up among different IO controllers, thus allowing flexible
automation concepts. You can,
for example, combine I/O modules that are physically close to each
other in one IO device.
Description Additional information
PROFINET function manual
(https://support.industry.sie
mens.com/cs/ww/en/view/4
9948856)
SIMATIC Drive Controller
Equipment Manual, 11/2019, A5E46600370-AA