Mitsubishi Electric Melsec QJ71LP21 - Routing Via a Redundant System

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MELSEC-Q
7 APPLICATION FUNCTIONS
7.10.8 Routing via a redundant system
This section describes the function of routing via a redundant system.
(1) Routing via a redundant system
To use the routing via a redundant system, set the network module mounted to
the control system CPU as a station to be routed.
Standby system (system B)
Q25H
CPU
Station
No. 3
Power supply module
Q25H
CPU
Station
No. 3
Control system (system A)
Network parameter settings
Destination
network No.
Relay
network No.
Relay
station No.
1
2 1
Network No. 2
Network No. 1
Power supply module
Redundant
CPU
Station
No. 1
Station
No. 1
Power supply module
Redundant
CPU
Station
No. 2
Station
No. 2
Power supply module
When the control system is switched, the routing parameter must be changed to
go through the station of the new control system.
Change the routing parameter with the RTWRITE instruction.
For a sample program in the following system configuration example, refer to (2)
of this section.
Control system (system B)
Power supply module
Redundant
CPU
Station
No. 2
Station
No. 2
Power supply module
Q25H
CPU
Station
No. 3
Power supply module
Q25H
CPU
Station
No. 3
Standby system (system A)
Power supply module
Redundant
CPU
Station
No. 1
Station
No. 1
Network parameter settings
Destination
network No.
Relay
network No.
Relay
station No.
1
2 1 2
Change this parameter
with the RTWRITE
instruction.
Network No. 2
Network No. 1
A communication
error occurs.