App - 2 App - 2
MELSEC
APPENDIX
(2) Operation at occurrence of system switching
When system switching occurs during access to the Redundant CPU, access to
the Redundant CPU set for the Logical Sta. No. is continued.
(Example) When the following Logical Sta. No.66 was specified for access
Logical Sta. No.66
Network No.:
1
Sta. No.:
1
Multiple PLC specify:
No specification
Redundant PLC specify: Control system
Before system switching
MELSECNET/H
(Network No.1)
Tracking cable
Station No. 3
Control system
Standby system
Station No. 2
Station No. 1
Personal computer
(MELSECNET/H board)
After system switching
MELSECNET/H
(Network No.1)
Tracking cable
Station No. 3
Control system
Standby system
Station No. 2
Station No. 1
Control system
Standby system
Personal computer
(MELSECNET/H board)
POINT
To judge which system in the Redundant CPU system is being accessed by MELSECNET/H
board, create a program to monitor the following special relays.
(1) When checking which system is being accessed, System A or System B
SM1511
System A
identification
flag
Identifies system A/system B of a redundant system.
Remains ON/OFF even if the tracking cable is disconnected while the redundant system
is running.
System A System B
At the time of TRK.CABLE ERR.(Error code:
6120) occurrence (System not determined.)
SM1512
System B
identification
flag
SM1511
ON
OFF
OFF
SM1512
OFF
ON
OFF
(2) When checking the operation system status
SM1515
Control/
Standby
system
status
Indicates the CPU module operation status
Remains ON/OFF even if the tracking cable is disconnected while the redundant system
is running.
Control
system
Standby
system
At the time of TRK.CABLE ERR.(Error code:
6120) occurrence (System not determined.)
SM1516
SM1515
ON
OFF
OFF
SM1516
OFF
ON
OFF
App.
Summary of Contents for Q80BD-J71BR11
Page 2: ......
Page 24: ...A 22 A 22 MEMO ...
Page 50: ...4 6 4 6 MELSEC 4 FUNCTION MEMO ...
Page 92: ...6 36 6 36 MELSEC 6 PROCEDURE AND SETTINGS UP TO THE POINT OF OPERATION MEMO ...
Page 132: ...10 2 10 2 MELSEC 10 MELSEC DATA LINK LIBRARY MEMO 10 ...
Page 138: ...11 6 11 6 MELSEC 11 PROGRAMMING MEMO ...
Page 164: ...12 26 12 26 MELSEC 12 APPLICATION FUNCTIONS MEMO ...
Page 166: ...13 2 13 2 MELSEC 13 ERROR CODE MEMO 13 ...
Page 223: ......