Setting The Sampling Times - Siemens SINAMICS S120 Function Manual

Commissioning
6.7 Commissioning Safety Integrated functions
6.7.4

Setting the sampling times

Terminology
The software functions installed in the system are executed cyclically at different sampling
times (p0115, p0799, p4099).
Safety functions are executed in the monitoring cycle (p9500) and the TM54F is executed
with the sampling time displayed in r10015. This sampling time corresponds to the lowest
value of the communication sampling time entered in p10000[0..5]. For Basic Functions, the
cycle is displayed in r9780.
Communication via PROFIBUS is performed cyclically via the communication cycle.
During the PROFIsafe scan cycle, the PROFIsafe telegrams issued by the master are
evaluated.
Rules
● The monitoring cycle (p9500) can be set between 500 μs to 25 ms.
Note
Setting an identical monitoring cycle
The monitoring cycle must be the same on all drives and the TM54F.
However, the calculation time required for the Extended/Advanced Functions in the
Control Unit depends on the monitoring cycle, that is, shorter cycles extend the
calculation time. The availability of a specific monitoring cycle therefore depends on
calculation time resources of the Control Unit.
CPU time resources on the Control Unit are influenced primarily by the number of drives,
the number of drives with enabled Extended/Advanced Functions, the connected
DRIVE-CLiQ components, the selected DRIVE-CLiQ topology, the use of a CBE20 and
by the selected technological functions. You can determine the number of axes that can
be controlled (closed loop) using the "SIZER" tool.
Note
Influence of deactivated drives on the required CPU time
Please note that the deactivated drives also affect the required CPU time. In the case of
utilization limits being reached, it is sufficient to deactivate one drive. This drive must then
be deleted.
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Function Manual, 12/2018, 6SL3097-5AR00-0BP1
Safety Integrated