Siemens S7-300 Configuration Manual page 127

Step 2: Assigning the device name to the CP as a PROFINET IO device
Continue with the configuration in HW Config as follows:
1. Open the properties dialog of the PROFINET IO device inserted in the PROFINET IO
2. In the "General" tab, assign the same device name that you entered for the PROFINET
3. Disable the "Assign IP address via IO Controller" option.
Configuring and commissioning S7 CPs for Industrial Ethernet
Configuration Manual, 09/2013, C79000-G8976-C182-13
Figure 7-2 SIMATIC station with PROFINET IO system
system.
port of the module in the S7 station (see section Enabling the CPU as a PROFINET IO
device in the S7 station (Page 124)).
This procedure is a recommendation!
Note:
With IO devices that are coupled with a module in a station in the configuration, the IP
address is specified by the settings on the module.
With this "explicit" coupling (as of STEP 7 V5.4 SP4), the consistency check in STEP 7
ensures that the IP addresses configured on the module and on the IO device match. The
"IP address assigned by IO controller" can therefore be enabled or disabled without any
functional effect.
With the procedure used up to now for these IO devices, the coupling of the IO device
with the module in the station using identical device names (implicit coupling), it is
generally recommended that you disable the "IP address assigned by IO controller"
option.
If the IP address configured in the S7 station happens to be overwritten, any configured
connections (S7, ISO-on-TCP, TCP) will no longer be established.
Intelligent PROFINET IO device with S7-300 CP
7.2 Configuration (STEP 7 V5.5)
127