Mitsubishi Electric MELSEC iQ-R-R00CPU User Manual page 441

Mode switching to the backup mode
The operation mode can be switched to the backup mode only in the communication path of when the operation mode was
switched to the separate mode.
The following describes the switching procedure for the backup mode.
1.
Set the CPU modules of the control system and standby system to have the same file configuration and operating status.
(To prevent an error detected by a restarted system consistency check after switching the separate mode to the backup
mode)
2.
Connect the engineering tool to the control system CPU module.
3.
Open the "Redundant Operation" window of the engineering tool.
[Online]  [Redundant PLC Operation]  [Redundant Operation]
4.
Select "Backup Mode" in "Change the Operation", and click the [Execute] button. The BACKUP LED of the redundant
function module turns on.
5.
When the tracking trigger has been turned off at the mode switching to the separate mode, turn on the tracking trigger.
( Page 459 Tracking trigger)
• Even when the CPU modules of both systems are simultaneously turned off and on or reset, the systems
start up in the backup mode at the next startup.
• When the control system CPU module has been turned off or reset in separate mode, the operation mode
can be switched from the separate mode to the backup mode in a different communication path by using the
engineering tool.
• When the operation mode is switched to the separate mode, the standby system CPU module is set to the
RUN-transition instruction waiting state (the PROGRAM RUN LED flashes). If the operation mode is
switched to the backup mode in this state, the CPU module is set to the RUN state (the PROGRAM RUN
LED stops flashing).
28 FUNCTIONS
28.1 Operation Mode Change
28
439