Siemens SIMATIC PCS 7 Configuration Manual page 147

Communication between H systems and standard AS
Note
Fault-tolerant AS-AS communication is not possible between fault-tolerant systems and
standard systems in PCS 7 as standard, meaning that AS-wide interconnections also cannot
be used.
You can instead create two standard S7 connections and then realize the fault-tolerance as
an application-specific block solution.
The following provide the options for this:
● Industry-Library (ASSendH and ASRecvH)
● Library S7H4_BSR (also for older PCS 7 versions)
You can find further information in the "SIMATIC Process Control System PCS 7 Industry
Library for PCS 7" (https://support.industry.siemens.com/cs/ww/en/view/81179761) manual.
Compendium Part A - Configuration Guidelines (V8.2)
Configuration Manual, 08/2016, A5E38166869-AA
Configuration of the network connections
7.2 Configuration of the connections
147