Redundant-Cpu-Compatible Function; Overview Of Redundant System Operation - Mitsubishi Electric MELSEC Q Series Reference Manual

4.7

Redundant-CPU-Compatible Function

This section explains the case of using the CC-Link IE Controller Network module with Redundant CPUs.
4.7.1

Overview of redundant system operation

(1) Cyclic transmission processing
System A
(control system)
Control station
No.1
LB0
LB7FFF
1.
A redundant system is composed of system A and system B, and the same send ranges for
respective stations in link devices (LB/LW) are set for stations of systems A and B.
2.
The station acting as the control system sends and receives cyclic data.
3.
The station acting as the standby system only receives cyclic data.
4.
The source CPU-side-device data in the own station's send range in the link devices (LB/LW) must
be tracking-transferred.
For details of tracking transfer, refer to the following.
QnPRHCPU User's Manual (Redundant System)
*1 Pairing is not available for communication using LX/LY.
*2 Tracking transfer is not available for link direct devices (J\).
*3 Do not use tracking transfer for the link special relay (SB0020 to SB01FF) and link special register (SW0020 to
SW01FF) that are turned ON/OFF by the system.
138
Redundant system
System B
(standby system)
Normal station
No.2
Tracking cable
4. Tracking transfer
Link relay (LB)
No.1, 2 send range
No.3
No.4
1. 2.
*2*3
Normal station
No.3
No.1, 2
No.3 No.3 send range
No.4 No.4
1. 3.
Normal station
No.4
No.1, 2
No.3
No.4 send range
*1