Precautions - Mitsubishi Electric MELSEC iQ-R Series User Manual

17.7

Precautions

This section describes the precautions when using the boot operation.
• When a parameter file is set as boot file, it overwrites the parameter file inside the transfer destination CPU module. In
addition, if a parameter file is not set as boot file even when stored on the SD memory card, the CPU module operates in
accordance with the settings in the parameter file inside it.
• If a program in the program memory is changed online during boot operation, the change is also reflected in the transfer
source program on the SD memory card.
• Note the model of the program written on the SD memory card (program specified in the boot file settings) and the model of
the CPU module must be the same.
• For the boot file setting, check that the setting is consistent with the program/label setting. When the file is read from the
programmable controller after the boot operation without consistency, conversion may not function properly due to lack of
consistency in project data.
Redundant system
This section describes precautions on using the boot operation in the redundant system.
■Boot operation at start-up of the redundant system
Use the boot operation only to simultaneously start up both systems.
1.
Attach SD memory cards that have boot setting data to both systems.
2.
Simultaneously turn off and on or reset both systems and perform the boot operation for them.
Do not use the boot operation to restart one system. If only one system is restarted with the boot operation, a system
consistency check error may occur. The following operations are recommended.
• Remove the SD memory cards for boot operation after simultaneously starting up both systems.
• When using an SD memory card for other applications, such as the data logging function, prepare another one.
■Online change in boot operation
It is recommended to remove SD memory cards for boot operation while the system is operating. Do not perform the online
change (online change (ladder block)). To copy project data to an SD memory card for boot operation, set the CPU module in
the STOP state and write the project data to the SD memory card.
■In redundant system with redundant extension base unit
When starting up the CPU modules of both systems simultaneously by boot operation, it is recommended to use the
automatic recovery function of the CPU module of the standby system.
Even if the CPU modules of both systems are started up simultaneously, if the start-up timing of one system is delayed due to
the time taken for booting, the CPU module of the system that was started up first cannot perform tracking communications
during initialization. Therefore, a stop error may occur in the CPU module of the system that was started up later.
In this case, if the automatic recovery function of the CPU module of the standby system is used, the system can be
recovered by automatically restarting the CPU module with a stop error. If the automatic recovery function of the CPU module
of the standby system is not used, the CPU module with a stop error must be restarted by manual operation.
17 BOOT OPERATION
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17.7 Precautions
17