Operation Mode Change; Procedures - Mitsubishi Electric MELSEC iQ-R Series User Manual

26.1

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.

Procedures

Execute the operation mode change to the CPU module of the control system from the "Redundant Operation" window of the
engineering tool.
Changing the operation mode to the separate mode
This section describes how to change the operation mode to the separate mode.
To prevent tracking transfer in separate mode, turn off the tracking trigger in advance. ( Page 394 Tracking trigger)
1.
Connect the engineering tool to the CPU module of the control system.
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 CPU module of the standby system enters the wait state for the RUN-transition instruction (same as the STOP
state), and the PROGRAM RUN LED flashes.
5.
Change the connection destination to the standby system on the engineering tool. Change the operating status of the
CPU module using the remote operation (remote STOP  remote RUN).
6.
The CPU module enters the RUN state and executes a program, and the PROGRAM RUN LED turns on.
For the step 5 (changing the operating status of the CPU module to the RUN state), the following methods are
also available.
• Changing the RUN/STOP/RESET switch from the STOP position to the RUN position
• Changing the operating status from the STOP state to the RUN state 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 when the CPU module of the control system is powered off and on or
* 1
reset.
• When the CPU module of the control system is powered off and on or reset, the system starts up as the control system in
separate mode.
• When the CPU module of the standby system is powered off and on or reset, the system starts up as the standby system in
separate mode.
• When the CPU modules of both systems are simultaneously powered off and on or reset, the systems start up in backup
mode.
*1 In a redundant system with redundant extension base unit, do not power off or reset the CPU module of the control system during
operation in separate mode because control cannot be continued.
Before powering off or resetting the CPU module of one system in separate mode, ensure the following:
• The other system has been started up and the READY LED is on.
• When the operating status of the CPU module in the other system has been changed to the RUN state, the PROGRAM
RUN LED is on.
If the CPU module of one system is powered off or reset during initial processing (when powered on/switched to RUN) of the
CPU module of the other system, the operation mode mismatch occurs between two systems and a stop error occurs.
26 REDUNDANT FUNCTION
26.1 Operation Mode Change
26
371