Siemens SIMATIC S7-400H System Manual page 365

Minimum cycle time
In STEP 7 you can set a minimum cycle time for a CPU. This is practical if
● the intervals between starting program execution of OB 1 (free cycle) are to be more or
● the cycle time were too short, the process images would be updated more often than
Figure 19-3 Minimum cycle time
The actual cycle time is the sum of T
S7-400H
System Manual, 03/2012, A5E00267695-11
less of the same length, or
necessary
and T . It is thus always longer or equal to T
cyc wait
S7-400 cycle and response times
19.3 Different cycle times
.
min
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