5
- 39
5.3 The System Switching Function
5.3.1 System Switching Method
5
POINT
1. If SM1592 is not turned ON at the time of system switching executed from GX
Developer, the error dialog box as Diagram 5.27 appears.
If the error dialog box as Diagram 5.27 has appeared, turn ON SM1592 and
then execute system switching again from GX Developer.
(b) System switching by the system switching instruction (SP. CONTSW
instruction)
*1
When the system switching instruction is executed in the control system CPU
module, the system switching is performed at END processing after instruction
execution.
1) The system switching by system switching instruction is done in the following
procedure:
•Turn on the "Enable/disable user system switching" flag (SM1592) in the
control system CPU module.
•Turn on the system switching instruction condition in the control system CPU
module and execute the instruction.
* 1: Refer to the following manual for details on the system switching instruction.
MELSEC-Q/L Programming Manual (Common Instruction)
Diagram 5.27 Error Dialog Box Displayed on GX Developer
Diagram 5.28 System Switching Operation by System Switching Instruction
System A -
Control
System
System B -
Standby
System
System A -
Control System
Standby System
System B -
Standby System
Control System
System switching
Calculating
Stopping Calculation
End calculation
Begin
calculating
Tracking cable
Tracking cable
System A
END
Control
system
System B
Standby
system
Control
system
RUN
(Execute program)
Normal Standby
RUN
(Stop program)
Normal Standby
RUN
(Stop program)
RUN
(Execute program)
Standby
system
System
switching
The system
swiching
instruction is
executed
SM1592
SP.CONTSW K1 M1
SP.CONTSW K2 M2
SP.CONTSW K3 M3
Enable manual system switching
Process Block 1
Process Block 2
Process Block 3