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6.2 Redundant System Network Overview
6.2.1 CC-Link IE Controller Network or MELSECNET/H PLC to PLC network
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6.2.1 CC-Link IE Controller Network or MELSECNET/H PLC to PLC network
In a redundant system, the data link is continued through system switching even when an
error occurs in the control system or control system network.
(1) Overview of Communication between Control System and Standby
System Network Modules
In a redundant system, the control system network module carries out cyclic data
communication, as the control system and standby system form one system.
The standby system network module receives cyclic data from the other station in
order to continue control even when system switching occurs.
Diagram 6.7 Communication between Control System and Standby System Network Modules
Receive only
Send and receive
Normal
station
(Station No. 3)
Control
system
Control
station
Normal
station
Normal
station
Normal
station
Standby
system
Normal
station
(Station No. 4)
Tracking cable
Send and receive
Send and receive
CC-Link IE Controller Network