Mitsubishi Electric Melsec QJ71LP21 Reference Manual page 365

7 APPLICATION FUNCTIONS
Control system
(system A)
Redundant Control
CPU station
Control
station
Q25H
CPU
Normal
station
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(b) When connecting a redundant system to an existing MELSECNET/H
network
The method for configuring a network depends on conditions 1) and 2)
shown below.
1) When connecting a redundant system as the control station
Change the previous control station to a normal station, and connect a
redundant system.
Set new network parameters to the redundant system using GX
Developer of version 8.18U or later.
Standby system
(system B)
Redundant
CPU
Tracking cable
Q25H
CPU
[Setting of the redundant CPUs]
1) Install network modules of function version D or later
to the redundant CPUs, and set one of them as the
control station.
2) Set the parameters for the redundant system using
GX Developer of version 8.18U or later.
Normal
station
Normal
station
[Setting of the previous control station]
1) Change the previous control station status to a normal
station.
MELSEC-Q
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