Siemens SIMATIC PROFINET Function Manual page 233

Multiple IO devices as a docking unit ("Alternating partner port")
A docking unit may also consist of several IO devices connected in series. If you use
IO devices connected in series as a docking unit, ensure that the topology of the IO devices
is configured. A docking unit consisting of two IO devices connected in series (Tool_3_1 and
Tool_3_2) is shown at the bottom right in the figure below.
Figure 5-95
Restriction in the interconnection
The interconnection with a partner port is not possible in the following cases:
● The partner port does not have a suitable type of cable. In this case, a media convertor
from the catalog must be inserted.
● The partner port is blocked (deactivated).
● The two ports that are to be interconnected belong to the same interface (it is only
possible to interconnect the ports from different interfaces in a station).
● The two ports that are to be interconnected belong to different Ethernet subnets.
Deleting interconnections
Select the port of the alternating partner and remove the interconnection with the "Remove"
button.
PROFINET with STEP 7 V14
Function Manual, 09/2016, A5E03444486-AG
Docking system in the topology view of STEP 7
Functions
5.11 Docking systems
233