System Switching Operation - Mitsubishi Electric MELSEC iQ-R Series User Manual

System switching operation

This section describes system switching operation when CC-Link is used in a redundant system.
When system switching can be followed
When the control system power supply module fails or a stop error occurs in the CPU module, the system and master
operating station are switched to continue controlling the slave station.
Control system
When system switching cannot be followed
When a system switching occurs due to the following system switching cause, the master station as a new standby system
still can make normal communications with the remote station and no switching to the standby master station will occur.
Because the standby master station of the new control system remains a standby master station, it cannot control the remote
station as a master station and therefore CC-Link cannot be controlled by the new control system.
The data link control must be switched from the standby master station to the master station using the new standby system
program.
For details on the program, refer to the communication example. ( Page 180 Communication examples)
• Execution of the system switching instruction
• System switching operation from the engineering tool
• System switching request from another network module
Appendix 8 How to Use Standby Master Function in Redundant System
A
APPX
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