I/O configuration variants
6.6 Versions of I/O connection to the PROFINET IO interface
CPU 410 Process Automation/CPU 410 SMART
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System Manual, 05/2017, A5E31622160-AC
Configuration
The following figure shows various different configurations for connecting IO devices to the
fault-tolerant system.
Figure 6-9
System redundancy
Configura-
tion
Properties
①
Switched I/O at the PROFINET IO
Each IO device is connected over one IM with two logic connections (system redundancy) to the two CPUs
in the fault-tolerant system.
This type of connection is also known as fault-tolerant PROFINET IO.
②
and
③
Switched I/O at the redundant PROFINET IO
Each IO device is connected over two IMs to the two CPUs in the fault-tolerant system. Each IM is assigned
to one of the CPUs. The IM must support system redundancy.
This type of connection is also known as redundant PROFINET IO.
This allows independent redundant PROFINET networks to operate in the fault-tolerant system. At the
same time, the two IMs increase availability.
In
③
, the connection to the CPU is also configured as a ring (redundant fault-tolerant PROFINET IO).
Note
Logical configuration and topology
The topology alone does not determine whether IO devices are configured at one side
(assigned to only one CPU in the fault-tolerant system) or in a system-redundant
configuration. This is specified in configuration. The IO devices in configuration
①
can, for
example, also be configured on one side instead of in a system-redundant configuration.