Configuring Networks - Siemens SIMATIC S7-400H Manual

8.2.3

Configuring Networks

The fault-tolerant S7 connection is a separate connection type of the "Configure
Networks" application. The following communication peers can communicate with
each other:
S7 H station (with 2 H-CPUs)
S7 400 station (with 1 H-CPU) –>
SIMATIC PC stations
Fault-tolerant connections are only permissible if at least one communications
terminal is an S7 H station.
When this type of connection is being configured, the application automatically
determines the number of possible connection paths:
If two independent but identical subnets are available which are both suitable
for an S7 connection (DP master systems), two connection paths will be used.
In practice these are generally electrical networks, each a CP in a subnet:
If only one DP master system is available – in practice typically fiber-optic
cables – four connection paths are used for a connection between two H
stations. All the CPs are in this subnet:
Downloading the network configuration to the H station
The network configuration can be downloaded to the entire H station in one go. To
do this, the same requirements must be met as for downloading the network
configuration to a standard station.
S7-400H Programmable Controller Fault-Tolerant Systems
A5E00068197-04
Configuring with STEP 7
–> S7 H station (with 2 H-CPUs)
S7 H station (with 2 H-CPUs)
–> S7 H station (with 2 H-CPUs)
8-5