Mitsubishi Q12PRHCPU - System Consistency Check

5
REDUNDANT SYSTEM FUNCTIONS
5.1 Basic Concept of Redundant System
5.1.4 System Consistency Check
5 - 16
1
OVERVIEW
2
SYSTEM CONFIGURATION
3
TRACKING CABLE
4
PROCEDURE FOR STARTING UP A REDUNDANT SYSTEM
5
REDUNDANT SYSTEM FUNCTIONS
6
REDUNDANT SYSTEM NETWORKS
7
PROGRAMMING CAUTIONS
8
TROUBLESHOOTING
5.1.4 System Consistency Check
In order to continue the redundant system control after system switching, the system
configurations, parameters and programs of the control system and standby system must
be consistent.
In the backup mode, the standby system CPU module checks if the system configurations,
parameters and programs of both systems are consistent. The redundant system
operates as shown below according to the check results.
*1
• If the control system and standby system are consistent in the system configuration,
parameters and programs, the redundant system operates normally.
• If the control system and standby system are inconsistent in the system configuration,
parameters and programs, an error will occur in the standby system CPU module.
* 1: This check is referred to as "Consistency Check Between Systems A and B".
The consistency check is executed in the following cases:
• When both systems are powered on simultaneously
• When both system CPU modules are unreset (RESET/L.CLR switch is set to the
neutral position) simultaneously.
• During END processing by the control system CPU module
• When the tracking cable is reconnected
Table5.9 shows consistency check points, and Table5.10 shows execution conditions.
Diagram 5.11 Consistency Check Points Between Systems A and B
Table5.9 Consistency Check Points Between Systems A and B
Check Points Description
(1) File Contents
Checks parameters, programs and initial device values.
Checks the memory capacity of the area for online change of multiple blocks.
(2) Operating Status Checks the CPU module operation status (RUN / STOP / PAUSE).
(3) Basic System Configuration
Checks the CPU modules, I/O modules and network modules mounted on the
main base units.
(4) Memory Card Setting
Checks the set memory card setting and the type, i.e., SRAM, Flash and ATA
card.
(5) Parameter Valid Drive Settings Checks the parameter valid drive settings (dip switch SW2,SW3)
Control
system
Standby
system
Tracking cable
(3) Check the base unit
installation status
(2) Check operating status
(5) Check the parameter usable drive
Check the memory
card installation status
RUN/STOP StatusRUN/STOP Status
Program File
Program File
Parameter File
Program File
Program File
Parameter File
(4)
Check file contents
(1)