Hello Experts,

I am confused with number of CP card required at the SCADA PC when using 2   S7 400H systems. 


Our project consists of  S7 400H systems with ET200  modules.    Two systems which are totally independant but has to share a common WinCC scada system. 

Please find the configuration attatched. 


I have 3 questions 

1.  How many number of CP1623/CP1613 A2   card are required when   two 400 H systems are to be connected to WinCC.  

a.  When WINCC is stand alone
b.  When WinCC is redundant servers


2.  How can i connect 400H stations to other vendor package for MODBUS
a.  Using one CP341  at ET200 station ?
b.  or two  CP441-2 at central rack?


C. Scalance model required at each station? 

About your question 1, then you NEED one but CAN (should) use two.

This is best explained in:

Fault-tolerant systems
S7-400H
System Manual
https://support.industry.siemens.com/cs/ww/en/view/82478488
14.6.3 Communication between fault-tolerant systems and PCs

PC software
Industrial Communication with
PG/PC Volume 1 - Basics
System Manual
https://support.industry.siemens.com/cs/ww/en/view/77376110
2.7.5.1 Fault-tolerant S7 connections, an overview

About redundand WinCC, then there is no difference to the cpu regarding a stand alone. The master and slave WinCC are seen as two WinCC systems. The master and slave just coordinate with each other who is the master.