APPX
Appendix 1 Precautions for Accessing Redundant CPU System
177
A
Checking the system to access target
To check which system in the Redundant CPU system is being accessed by the CC-Link IE Field Network board, create a
program to monitor the following special relays.
The flag status does not change even if the tracking cable is disconnected.
• When checking which system is being accessed, System A or System B
• When checking the operation system status
Retry processing for the error that occurs during system
switching processing
When the MELSEC data link library is used to access the Redundant CPU during system switching being processed by the
Redundant CPU, a system switching error (error code: 4248H), CPU starting error (error code: 4004H), other system CPU
module error (error code: 4245H), access destination illegal error (error code: FFDFH) or similar error occurs.
In this case, create a user program that checks the error code and performs retry processing as necessary.
Functions that result in error if executed during system switching
<After system switching>
Special relay
System A
System B
At the time of TRK.CABLE
ERR. (Error code: 6120)
occurrence (System not
determined.)
SM1511 (System A identification flag)
ON
OFF
OFF
SM1512 (System B identification flag)
OFF
ON
OFF
Special relay
Control system
Standby system
At the time of TRK.CABLE
ERR. (Error code: 6120)
occurrence (System not
determined.)
SM1515 (Control system judgment
flag)
ON
OFF
OFF
SM1516 (Standby system judgment
flag)
OFF
ON
OFF
Functions that result in error by system switching
MELSEC data link library
mdDevSetEx, mdDevRstEx, mdRandREx, mdRandWEx, mdReceiveEx, mdSendEx, mdControl, mdDevRst,
mdDevSet, mdRandR, mdRandW, mdReceive, mdSend, mdTypeRead
MELSECNET/H
Station No.5
Station No.4
Station No.3
Station No.2
Station No.1
Standby system
Control system
Control system
Standby system
CC-Link IE Field Network module
MELSECNET/H module
CC-Link IE Field Network
(Network No.1)
(Network No.2)
Tracking cable
Summary of Contents for MELSEC Q80BD-J71GF11-T2
Page 2: ......
Page 6: ...4 Disposal Precautions CAUTION When disposing of this product treat it as industrial waste ...
Page 118: ...116 12 MONITORING MEMO ...
Page 140: ...138 14 MELSEC DATA LINK LIBRARY MEMO ...
Page 142: ...140 15 PROGRAMMING 15 1 Precautions on Programming MEMO ...
Page 243: ...241 I U Utility 83 ...
Page 247: ......