Operation At System Switching - Mitsubishi Electric MELSEC iQ-R-R00CPU User Manual

Operation at system switching

The following table shows the operations of the CPU modules of when the control system and the standby system are
switched.
These operations are for when both systems are operating and the operating statuses of the CPU modules are the same.
Item
Program Standard
execution program
Safety
program
Tracking transfer
Online Online
change change
(ladder
block)
File batch
online
change
Device/label memory (standard label, safety
label, standard/safety shared label)
Signal flow memory
(standard/safety
program)
Setting the device/label initial value
Special relay (SM), special register (SD)
Safety special relay (SA\SM), safety special
register (SA\SD)
Output (Y)
Safety output device (SA\Y)
Safety CC-Link IE Field Network (CPU
module  Master/local module)
output
37 FUNCTIONS
614
37.1 System Switching
New control system CPU module
Initial execution This type of program is not executed.
type program However, when an initial execution type program has not
been completed on the old control system at system
switching, it is executed again from its head.
Scan execution type This type of program is executed from the step 0.
program
Fixed scan The fixed scan execution interval is measured from 0.
execution type
program
Standby type This type of program is not executed.
program
Event execution • Interrupt program: The program is executed when an
type program interrupt factor is generated.
• ON of bit data (TRUE): The program is executed when
a specified factor is generated.
• Passing time: A specified time is measured from 0.
Fixed scan The fixed scan execution interval is measured from 0.
execution type
program
Tracking data is transferred to the new standby system.
Standard program Write operation at system switching continues.
Safety program Safety programs cannot be changed online.
Standard program Write operation at system switching continues.
Safety program Safety programs cannot be changed online.
The state before system switching is held.
With tracking setting The signal flow of the old control system is reflected.
Without tracking The signal flow of the tracking transfer targets is turned
setting on.
The values are not set.
The state before system switching is held.
However, when the CPU module is in the RUN state, SD520 to SD531 and SD1890 to SD1895 are cleared.
The state before system switching is held.
The safety special relay areas/safety special register areas related to safety communications (SA\SM1008,
SA\SM1016, SA\SM1024, SA\SM1032, SA\SM1040, SA\SM1048, SA\SM1056, SA\SM1064, SA\SM1088,
SA\SD1008 to SA\SD1071, SA\SD1088, SA\SD1089, SA\SD1090 to SA\SD1097, SA\SD1104 to
SA\SD1223, SA\SD1232 to SA\SD1359, and SA\SD1600 to SA\SD1663) are cleared.
The state before system switching is held.
After a safety program which is the fixed scan execution
type is operated using transferred device data, data is
*2
output.
New standby system CPU module
*1
The program execution stops.
The program execution stops.
Tracking data is received. However, when a
stop error occurs on the new standby system,
the new standby system does not receive the
tracking data.
The state before system switching is held.
The state is held when the standby system
output setting of the redundant system
operation setting is enabled. If the setting is
disabled, the output (Y) is turned off and then
the output refresh stops.
The safety output device (SA\Y) is turned off
regardless of the standby system output setting.
Refresh processing is stopped because the
safety connection is disconnected.