Siemens Sinamics S120 Function Manual page 644

Communication
10.3 Communication via PROFINET IO
Table 10- 61 Settable send cycles and update cycles
Send cycle
Range 250, 500,
"even" 1000 µs
1)
2000 µs
4000 µs
Range 375, 625, 750,
"uneven" 875, 1125,
3)
1250 µs ...
3875 µs
(increment
125 µs)
Note
There is no intersection between the send cycles for the "even" and "uneven" ranges!
Explanations for the above table:
1) It is only possible to set send cycles from the "even" range when IO devices with RT class
"RT" are assigned to a synchronization domain. Likewise, only the reduction ratios from the
"even" range can be set for a send cycle setting from the "even" range.
2) It is generally only possible to set a reduction ratio of 1:1 between the update time and
send cycle for IO devices (ET200S IM151-3 PN HS, SINAMICS S) which are operated in
isochronous mode. In this case, the update cycle mode must always be set to "fixed factor"
(under I/O device properties, "IO cycle" tab, "Mode" pulldown menu). This means that STEP
7 will not automatically adjust the update cycle and thus the update cycle will always
correspond to the send cycle.
3) The send cycles from the "uneven" range can be set only if a synchronization domain
does not include any IO devices with RT class "RT". Likewise, only the reduction ratios from
the "uneven" range can be set for a send cycle setting from the "uneven" range.
4) Isochronous operation is not compatible with IRT "high flexibility".
5) Uneven send cycles can be used only if the IO systems assigned to the synchronization
domain do not include any RT or IRT "high flexibility" devices.
Furthermore, the send cycles which can actually be set are determined by the intersection of
the send cycles supported by all the devices in the synchronization domain.
The reduction ratio between the update cycle of an IO device and the send cycle is set in the
"Properties" of the PROFINET interface for the relevant device.
Send cycles for SINAMICS drive units
A SINAMICS drive unit with PROFINET interface which supports IRT permits send cycle
settings of between 0.5 ms and 4.0 ms in a 250 µs time frame.
642
Reduction ratio between update and send cycles
RT
IRT "high flexibility"
4)
1.2.4.8.16.32.64.128.256.512
1.2.4.8.16.32.64.128.256
1.2.4.8.16.32.64.128
not supported 5)
IRT "high performance"
1.2.4.8.16
2)
1.2.4.8.16
2)
1.2.4.8.16
2)
1
Function Manual, (FH1), 01/2012, 6SL3097-4AB00-0BP2
Drive functions