Mitsubishi Electric MELSEC Q80BD-J71GF11-T2, User Manual

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180
APPX
Appendix 1 Precautions for Accessing Redundant CPU System
<Figure 2 When system switching occurs due to standby system error>
• Path switching is not executed when a communication to the Redundant CPU specified at Logical station
No. is faulty at communication start
*1
(A communication error occurs.)
When a communication is faulty, refer to the following and clear the communication disturbance.
(

Page 179 Checking method of path switching occurrence, Page 179 Access examples of path
switching)
• If other station access (including the programmable controller CPU other than the Redundant CPU) is made
to 257 or more stations simultaneously, communication path may not be automatically switched.
*1 First communication after execution of the mdOpen function in the MELSEC data link library (communications using the mdReceiveEx,
mdSendEx, mdDevRstEx, mdDevSetEx, mdRandREx, mdRandWEx, mdReceive, mdSend, mdControl, mdDevRst, mdDevSet,
mdRandR, mdRandW or mdTypeRead function).
MELSECNET/H
MELSECNET/H
Control system Standby system
Control system Standby system
Standby system
error
Connection to the
control system
Connection to the
control system
CC-Link IE Field Network module
MELSECNET/H module
CC-Link IE Field Network
CC-Link IE Field Network
CC-Link IE Field Network module
MELSECNET/H module
Tracking cable
Tracking cable
Personal computer
(CC-Link IE Field
Network board)
Personal computer
(CC-Link IE Field
Network board)