Siemens SIMATIC S7-1500 Function Manual page 342

Setting up a connection via a device IP address
To set up an OUC-connection via a device IP address of one of the two CPUs:
● Select a suitable PROFINET interface of the S7-1500R/H redundant system.
● Deselect the "Use address of H-system" check box.
Figure 13-14 OUC-connection via a device IP address
Reference
You can find additional information on system states in the S7-1500R/H
(https://support.industry.siemens.com/cs/ww/en/view/109754833) system manual.
See also
PROFINET FUNCTION MANUAL
(https://support.industry.siemens.com/cs/ww/en/view/49948856)
Communication
Function Manual, 11/2019, A5E03735815-AH
Communication with the redundant system S7-1500R/H
13.6 Open User Communication with the redundant system S7-1500R/H
341