Siemens SIMATIC ET 200AL System Manual page 1868

Additional IO controllers can also be connected as I-device to the redundant S7-1500R/H
system. An I-device is connected like a standard IO device to the redundant S7-1500R/H
system.
The redundant S7-1500R/H system supports the use of I-devices only via GSD file and as
standard IO device.
Figure 6-7
PROFINET with STEP 7
Function Manual, 05/2021, A5E03444486-AL
6.7 Configuring PROFINET IO on a redundant S7-1500R/H system
I-device downstream of a switch
PROFINET with the redundant S7-1500R/H system
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