/tf/WW/en/Posts/31590#top

The only way you can use a single-interface Profibus-DP slave on a SWR system is to set it up in the non-redundant part of your program. See the SWRmanual for more information:
SIMATIC S7-300/S7-400 Software redundancy for SIMATIC S7

See the following section in particular:
5.9 Data blocks DB_A_B and DB_B_A for the exchange of non-redundant data
Hope this helps,
Daniel Chartier