Supplementary information
18.16 CPU 410 cycle and reaction times
CPU 410 Process Automation/CPU 410 SMART
System Manual, 05/2017, A5E31622160-AC
361
Extending the cycle time
The calculated cycle time of a S7-400H CPU must be multiplied by a CPU-specific factor.
The table below lists these factors:
Table 18- 12 Extending the cycle time
Startup
CPU 410-5H stand-alone mode
CPU 410-5H redundant
Factor
1.05
1.2
Long synchronization cables may increase cycle times. This extension can have the factor 2
- 5 with a cable length of 10 km.
Operating system execution time at the cycle control point
The table below shows the operating system execution time at the cycle checkpoint of the
CPUs.
Table 18- 13 Operating system execution time at the cycle control point
Sequence
CPU 410-5H stand-alone mode
CPU 410-5H redundant
Cycle control at the SCCP
25 - 330 µs
∅
30 µs
120 - 600 µs
∅
135 µs
Extended cycle time due to nested interrupts
Table 18- 14 Extended cycle time due to nested interrupts
CPU
Hardware
interrupt
Diagnostic
interrupt
Time-of-
day inter-
rupt
Delay interrupt
Cyclic
inter-
rupt
Programming
error
I/O
access
error
Asyn-
chronous
error
CPU 410-5H
stand-alone
mode
75 µs
40 µs
50 µs
40 µs
40 µs
20 µs
20 µs
55 µs
CPU 410-5H
redundant
180 µs
70 µs
200 µs
120 µs
120 µs 90 µs
45 µs
130 µs
The program runtime at interrupt level must be added to this time extension.
If several interrupts are nested, their times must be added together.