Siemens SIMATIC PCS 7 - Page 333

Supplementary information
18.11 Communication via fault-tolerant S7 connections
CPU 410 Process Automation/CPU 410 SMART
System Manual, 05/2017, A5E31622160-AC
333
Local connec-
tion
end point
Local network con-
nection
Used network
protocol
Remote
network connection
Remote connec-
tion
end point
PC station
with Simatic
Net CD
PC station with Si-
matic Net CD
CP1613/1623/1628,
V8.1.1 or higher
TCP
TCP
CPU-PN interface
CP443-1 ( EX 30)
TCP
TCP
CPU 41xH
V6/CPU 410
CPU 41xH V4.5
and higher/CPU
410
S7 fault
tolerant
connection
via
ISOonTCP
PC station
with Simatic
Net CD
for example CP1623
with Simatic Net,
V8.1.2 or higher
ISO CP443-1 ISO CPU 41xH /CPU
410
S7 fault
tolerant
connection
via ISO
PC station
with Simatic
Net CD
for example CP1623
with Simatic Net up
to V7.x
ISO CP443-1 ISO CPU 41xH /CPU
410
S7 fault
tolerant
connection
via ISO
Configuration
The availability of the system, including the communication, is set during configuration. Refer
to the STEP 7 documentation to find out how to configure connections.
Only S7 communication is used for fault-tolerant S7 connections. To set this up, open the
"New Connection" dialog box, then select "S7 Connection Fault-Tolerant" as the type.
The number of required redundant subconnections is determined by STEP 7 as a function of
the redundancy nodes. Up to four redundant connections can be generated, if supported by
the network. Higher redundancy cannot be achieved even by using more CPs.
In the "Properties - Connection" dialog box you can also modify specific properties of a fault-
tolerant connection if necessary. When using more than one CP, you can also route the
connections in this dialog box. This may be practical, because by default all connections are
routed initially through the first CP. If all the connections are busy there, any further
connections are routed via the second CP, etc.
You have to extend the monitoring time of the connection when you use long
synchronization cables.
Example: If you are operating 5 fault-tolerant S7 connections with a monitoring time of
500 ms and short synchronization cables up to 10 m and you want to change these to long
synchronization cables with a length of 10 km, you must increase the monitoring time to
1000 ms.
To ensure CIR capability of the fault tolerant system, you must activate the "Save
connections prior to loading" option in Step 7 NetPro.
Programming
Fault-tolerant communication is supported on the fault-tolerant CPU and is implemented
using S7 communication.
This is possible only within an S7 project/multiproject.