Siemens SCALANCE X-200RNA, Руководство по эксплуатации

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Network topologies and redundancy
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3.1 PRP
Parallel Redundancy Protocol
The "Parallel Redundancy Protocol" is a redundancy protocol for Ethernet networks. It is
defined in Part 3 of the IEC 62439 standard. The devices of the SCALANCE X-200RNA product
line support the PRP method. The areas of application of PRP are distributed real-time
applications with high reliability demands that depend on the high availability of the network.
Compared with classic fault-tolerant networks, PRP provides bumpless redundancy. This
redundancy method allows data communication to be maintained without interruption/
reconfiguration time if there are interruptions in the network. Other redundancy methods have
a network reconfiguration time of, for example 200 ms (MRP, 50 nodes in the ring) or 300 ms
(High Speed Redundancy, 50 nodes in the ring) and cannot therefore be used for substation
applications or other applications that require high network availability.
The PRP method has the advantage that it uses parallel, separate networks made up of
standard network components. The end devices that use this method are connected to the
two networks via a preceding device or via two integrated device interfaces. This means that
the frame of the end device can be transferred at the same time via both networks. If a
transmission path is interrupted, the frame arrives at its destination via the second path.
The devices of the SCALANCE X-200RNA product line are used to connect end devices
without integrated PRP interfaces to parallel networks.
Note
SCALANCE X204RNA EEC (PRP/HSR)
If you initialize the device as a PRP device, it behaves in exactly the same way as the
SCALANCE X204RNA EEC (PRP).
Which topologies can be implemented?
With the devices of the SCALANCE X-200RNA (PRP) product line, nodes or entire network
segments without PRP capability can be connected to a "Parallel Redundancy Protocol"
network.
The products with PRP capability of the SCALANCE X-200RNA product line can be used to
implement an integrated solution for network components and protective devices for a
substation and also process application.
SCALANCE X-200RNA
Operating Instructions, 10/2016, C79000-G8976-C342-04
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