ABB REF615 ANSI 5.0 FP1 Product Manual page 31

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HSR applies the PRP principle of parallel operation
Figure 15. Parallel
redundancy proto-
to a single ring. For each message sent, the node
col (PRP) solution
sends two frames, one through each port. Both the
frames circulate in opposite directions over the
ring. Every node forwards the frames it receives
from one port to another to reach the next node.
When the originating sender node receives the
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COM600
Ethernet switch
IEC 61850 PRP
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frame it sent, the sender node discards the frame
to avoid loops. The HSR ring with 615 series relays
supports the connection of up to 30 relays. If more
than 30 relays are to be connected, it is recom-
mended to split the network into several rings to
guarantee the performance for real-time applica-
tions.
SCADA
Ethernet switch
REM620
31
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