Operation Mode Change; Switching Procedure - Mitsubishi Electric MELSEC iQ-R-R00CPU User Manual

28.1

Operation Mode Change

This function switches the operation mode of the redundant system between the backup mode for normal operation and the
separate mode for system maintenance while it is running.

Switching procedure

Switch the operation mode of the control system CPU module in the "Redundant Operation" window of the engineering tool.
Mode switching to the separate mode
The following describes the switching procedure for the separate mode.
To prevent tracking transfer in separate mode, turn off the tracking trigger in advance. ( Page 459 Tracking trigger)
1.
Connect the engineering tool to the control system CPU module.
2.
Open the "Redundant Operation" window of the engineering tool.
[Online]  [Redundant PLC Operation]  [Redundant Operation]
3.
Select "Separate Mode" in "Change the Operation", and click the [Execute] button. The SEPARATE LED of the
redundant function module turns on.
4.
The standby system CPU module is set to the RUN-transition instruction waiting state (same as the STOP state), and the
PROGRAM RUN LED flashes.
5.
Set the standby system as the connection destination with the engineering tool, and execute the remote STOP and then
the remote RUN with the remote operation function.
6.
The CPU module is set to the RUN state and executes a program, and the PROGRAM RUN LED turns on.
For the step 5, the following methods are also available for setting the CPU module to the RUN state.
• Setting the RUN/STOP/RESET switch in the STOP position to the RUN position
• Setting the module in the STOP state to the RUN state by using the RUN-PAUSE contact
■Powering off and on or resetting the CPU module in separate mode
In separate mode, the systems are not switched even if the control system CPU module is turned off and on or reset.
• When the control system CPU module is turned off and on or reset, the system starts up as the control system in separate
mode at the next startup.
• When the standby system CPU module is turned off and on or reset, the system starts up as the standby system in
separate mode at the next startup.
• 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.
Before turning off or resetting one system in the separate mode, check if the other system is in the following status.
• The other system has been started and the READY LED is on.
• When the other system is set to the RUN state, the PROGRAM RUN LED is on.
If one system is turned off or reset while the other system is in the initial processing or initial processing (when switched to
RUN), the operation modes of both systems become different and a stop error occurs.
28 FUNCTIONS
438
28.1 Operation Mode Change