Mitsubishi Electric MELSEC iQ-R Series User Manual page 730

■Tracking data reflection time (Trc)
The following describes the tracking data reflection time (Trc) in the CPU module of the standby system. The calculation
method differs depending on whether an extended SRAM cassette is inserted or not.
Extended SRAM cassette inserting status
Not inserted
Inserted
• D1: Size [word] of tracking data in the system data, signal flow memory, refresh data register (RD), and module label
(extension base unit)
• D2: Size [word] of tracking data of global devices, local devices, global labels, and local labels
• D4: Size [word] of tracking data in the system data, signal flow memory, and refresh data register (RD)
• D5: Size [word] of tracking data of global devices, local devices, global labels, and local labels
• E1: Additional time when the SFC program is used = 4.0[ms] (Only when the SFC program is used)
• F1: Additional time when the PID control instruction is used = 0.02[ms] (Only when the PID control instruction is used)
• G1: Number of transferred blocks
For the calculation formula for the size of tracking data, refer to the following.
Page 725 Tracking data send time (Tst)
■Other extended times ()
When an error occurs during a tracking transfer, the scan time may be extended ().
Item
In a redundant system with redundant extension base unit, when
disconnection of the tracking cable, disconnection of the redundant function
module, or redundant function module failure has occurred
*1 This does not apply in the configuration with the main base unit only.
Increase in the scan time in a redundant system with redundant extension base unit
In a redundant system with redundant extension base unit, the scan time becomes longer (END processing) because the
CPU module of the control system checks the connection status of the extension cable. The following shows the increase in
the scan time caused by checking the connection status of the extension cable.
• Control system: 10s
• Standby system: 0s
Extended time required for detecting a system switching cause
The following describes the extended time required from occurrence of a system switching cause for the CPU module or
redundant function module in the control system to the detection of a system switching request, or the extended time required
for the CPU module to detect a system switching request sent from the network module.
System switching cause
Power-off
CPU module hardware failure, CPU
module stop error
System switching request from a network module
System switching request by the SP.CONTSW instruction
System switching request from the engineering tool
APPX
728
Appendix 7 Processing Time
Tracking data reflection time
-6
1+ (20.0  10
-6
1+ (20.0  10
When the tracking communication
cannot be made
When the tracking communication
can be made
-6
)  D1 + (37.2  10 )  D2 + E1 + F1 + (300.0  10
-6
)  D1 + (106.0  10 )  D2 + E1 + F1 + (300.0  10
* 1
Time for 
Maximum of 60 [ms]
Extended time required for detecting a system switching cause
19.26 to 38.83ms
10ms
0ms
0ms
0ms
0ms
-6
)  G1[ms]
-6
)  G1[ms]