Mitsubishi QJ71LP21 User Manual

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MELSEC-Q
4 SETUP AND PROCEDURES BEFORE STARTING THE OPERATION
(b) Setting the mode when performing the forward loop/reverse loop test on the
redundant system
When conducting the forward loop/reverse loop test on the redundant
system, set the operation mode of the redundant CPU to the backup mode
in advance.
When it the power supplies of both the systems cannot be powered on/off,
perform the forward loop/reverse loop test in the separate mode.
The table below shows the mode settings when conducting the forward
loop/reverse loop test on the redundant system.
Target station Set-up
In backup mode
Test target station
Redundant
system
In separate mode
Set to "forward loop test"
or "reverse loop test."
In backup mode Set to "offline."
Redundant
system
In separate mode Set to "online."Non-test target station
Remote I/O station Set to "online."
The figure below shows the settings when the forward loop test is executed
on the system A (station No. 1) of the redundant system (in the backup
mode).
Redundant
CPU
Station
No. 1
Redundant
CPU
Station
No. 0
Power
supply
module
QJ72
LP25
QJ72
LP25
Control system
(system A)
Standby system
(system B)
Set the mode of the system B (station No. 1)
to "offline."
Set the mode of the system A (station No. 0)
to "forward loop test."
Remote I/O station Remote I/O station
Station
No. 2
Station
No. 3
Power
supply
module
Power
supply
module
Power
supply
module

Mitsubishi QJ71LP21 Specifications

General

Brand	Mitsubishi
Model	QJ71LP21
Category	Controller
Language	English