Siemens SIMATIC CPU 410 System Manual page 75

Configuration with two IO devices with independent, system-redundant connection
This configuration has the following advantage: The complete system can continue operating
after a wire break, no matter where the wire break is located. One of the two communication
connections of the IO devices is always retained. The IO devices that are redundant up this
point continue operating as one-sided IO devices.
Network addresses on the PROFINET IO subsystem
In a redundant configuration, the network addresses of the interface modules must be
unique across both PROFINET IO subsystems.
● In a ring structure, all network addresses must be within a PROFINET IO subsystem and
you must specify the MRP role for each node.
● In the case of system redundancy with two subnets, the two interface modules of a
station must be assigned to the following PROFINET IO subnet:
– Interface module in slot 0 of the IO device is assigned to rack 0 of the IO controller.
– Interface module in slot 1 of the IO device is assigned to rack 1 of the IO controller.
Commissioning of a system-redundant configuration
It is imperative that you assign unique names when commissioning.
When you change a project or download a new project, follow these steps:
1. Put the fault-tolerant system in STOP state on both ends
2. Perform a memory reset of the standby CPU
3. Download the new project to the master CPU
4. Start the Fault-tolerant system
Note
To edit the topology of a project, use the topology editor in HW Config.
S2 and R1 devices
S2 device: There is one IM connected to both CPUs.
R1 device: There are two IM (redundant). Each IM is connected to one CPU.
CPU 410 Process Automation/CPU 410 SMART
System Manual, 05/2017, A5E31622160-AC
6.6 Versions of I/O connection to the PROFINET IO interface
I/O configuration variants
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