Scan Configuration - Mitsubishi Electric MELSEC iQ-R-R00CPU User Manual

35.7

Scan Configuration

This section describes scan configurations of the CPU modules in a system using the SIL2 Process CPU.
Tracking transfer is performed during the END processing. ( Page 622 Tracking Transfer)
For details on the scan configuration other than tracking transfer, refer to Chapter 1. ( Page 38 Scan Configuration)
The following figure shows scan configurations of when both systems are started up simultaneously.
<Control system>
Initial processing
(when switched to RUN)
Scan
time
Both systems perform different processing.
: Performed, : Not performed
Processing
Initial processing/initial processing (when switched to RUN)
I/O refresh
Program operation
Tracking transfer
END processing
*1 Only the input refresh is performed. Whether or not to perform the output refresh depends on "Standby System Output Setting" of "CPU
Parameter". ( Page 652 Redundant System Operation Setting)
*2 The program operation is not performed with the default setting. Programs are executed according to "Both Systems Program
Executions Setting" in "Program Setting" of "CPU Parameter". ( Page 647 Program Execution in Both Systems)
35 BASIC CONCEPT
568
35.7 Scan Configuration
CPU module is
switched to RUN
I/O refresh
Program operation
END processing
Sending tracking data
Tracking transfer
Reception completion of
tracking data
<Standby system>
CPU module is
switched to RUN
Initial processing
(when switched to RUN)
I/O refresh
Operation of the program
executed in both systems
END processing
Tracking transfer
Control system





Scan
time
Standby system

*1

*2


