Virtual Time Response - Siemens Simatic S7-1500 Function Manual

Virtual time response

The virtual controller uses internally two types of clocks for simulation: A virtual clock and a
real clock. The virtual clock is always the basis for the user program. It is used by
components that are relevant for running the STEP 7 user program, such as cyclic OBs,
cycle time monitoring, minimum cycle time, virtual system time and time calculations. Also,
the time between two cycle control points is measured in virtual time.
The virtual time can be accelerated or slowed for test purposes.
The real clock always runs unchanged. It is used by components that are not subject to
control processes, for example, communication with STEP 7.
Virtual system time
When you start PLCSIM Advanced, the virtual system time of the virtual controller starts with
the system time of Windows.
The virtual system time is based on the virtual clock, i.e. if a scaling factor is used, the
system time runs correspondingly faster or slower.
All events that the virtual controller sends to the API provides a time stamp based on the
system time.
Note
Difference between system time and local time
• System time: UTC ± 0 with daylight saving / standard time
• Local time: UTC ± time zone with daylight saving time / winter time
API functions
● GetSystemTime() (Page 220)
● SetSystemTime() (Page 221)
● SystemTime { get; set; } (Page 221)
Time offset
Note
Keep in mind that the time information of virtual system time and real local time differs by the
time offset that is formed in addition to the selected scaling factor from the time zone offset
and the daylight saving time/standard time offset.
S7-PLCSIM Advanced
Function Manual, 12/2017, A5E37039512-AB
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