Siemens Simatic S7-1500H, Системное руководство, Страница: 23 / 327

System overview
2.1 What is the S7-1500R/H redundant system?
S7-1500R/H redundant system
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System Manual, 10/2018, A5E41814787-AA
The S7-1500H redundant system consists of:
● Two S7-1500H CPUs
①
● A PROFINET ring with the Media Redundancy Protocol
②
● Two redundancy connections
③
● IO devices
④
● if needed, Switches
⑤
All nodes in the redundant system must support system redundancy S2 and media
redundancy (MRP).
All PROFINET IO devices assigned to the S7-1500H system must support system
redundancy S2. These PROFINET IO devices can be located in the PROFINET ring or they
can be separated with a switch.
All PROFINET devices in the PROFINET ring must support media redundancy (MRP).
System redundancy S2 is not a prerequisite. For example, you can use switches and HMI
devices without system redundancy S2.
As with S7-1500R, the S7-1500H redundant system requires a PROFINET ring
②
closed by
the CPUs. All nodes can still communicate with each other in the event of an interruption in
the ring. Devices that do not support MRP must be separated from the ring with a switch
⑤
.
Unlike in S7-1500R, the PROFINET ring and redundancy connections in S7-1500H are
separate. The two redundancy connections are fiber-optic cables that connect the CPUs
directly over synchronization modules
③
.
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.
Synchronization of primary and backup CPU ensures rapid switchover between CPUs in the
event of a failure of the primary CPU. If the primary CPU fails, the backup CPU takes over
control of the process as the new primary CPU.
The synchronization of the H-CPUs does not affect the bandwidth on the PROFINET.