Siemens SIMATIC S7-1500 System Manual page 31

The figure below shows a configuration of the S7-1500H with R1 devices in a line topology
①
②
③
④
⑤
Figure 4-8 S7-1500H configuration with R1 devices in a line topology
S7-1500H without additional devices at the X1 interface of the H-CPUs
The configuration with only 2 H-CPUs is suitable for all applications that do not require any
additional devices at the PROFINET interface X1 P1R/X1 P2R of the H-CPUs (e.g., Modbus/TCP):
①
②
Figure 4-9 S7-1500H configuration with additional devices
Principle of operation
Unlike in S7-1500R, the PROFINET ring (PROFINET network) and redundancy connections in
S7-1500H are separate. The two redundancy connections are fiber-optic cables that connect
the CPUs directly over synchronization modules.
One of the two CPUs in the redundant system takes on the role of primary CPU. The other
CPU takes on the role of the following CPU (backup CPU). The role of the CPUs can change
during operation.
S7-1500R/H redundant system
System Manual, 11/2022, A5E41814787-AD
H-CPU
Redundancy connections (fiber-optic cables)
PROFINET cable (line topology 1)
PROFINET cable (line topology 2)
IO device (with R1 system redundancy)
H-CPU
Redundancy connections (fiber-optic cables)
4.1 What is the S7-1500R/H redundant system?
System overview
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