Siemens SINAMICS S120, Function Manual

Page: 1010 / 1094

Basic information about the drive system
13.12 System rules, sampling times and DRIVE-CLiQ wiring
Drive functions
1010
Function Manual, 11/2017, 6SL3097-4AB00-0BP5
The following supplementary conditions must be observed for isochronous operation:
● The PROFIBUS cycle T
dp
must be an integer multiple of 250 μs.
● The PROFIBUS cycle T
dp
must be an integer multiple of the current controller sampling
time.
● The times T
i
(time of incorporation of actual value) and T
o
(time for setpoint value
specification) must be integer multiples of 125 μs .
● The times T
i
and T
o
must be an integer multiple of the current controller sampling time.
● T
mapc
is an integer multiple of the speed controller sampling time.
● Because T
i
and T
o
are always predefined for a PROFIBUS line, all drives of a Control Unit
are affected and run with the same setting.
● p0092 = 1 (isochronous operation preassignment/validation) sets default values for the
controller cycles for isochronous PROFIdrive operation during the initial commissioning.
–
The current controller sampling times from "Table 13-14 Pulse frequencies and current
controller sampling times for servo control (Page 1026)" can be set for servo control.
– The current controller sampling times from "Table 13-16 Pulse frequencies and current
controller sampling times for vector control (Page 1028)" can be set for vector control.
● The setting rules for the safety actual value acquisition cycle and the safety monitoring
cycle must be observed (for details, see SINAMICS S120 Safety Integrated Function
Manual):
–
The monitoring cycle (p9500) must be an integer multiple of the actual value
acquisition cycle (p9511). For p9511 = 0, the isochronous PROFIBUS cycle T
dp
is
used as the actual value acquisition cycle.
– Actual value acquisition cycle ≥ 4 × current controller sampling time.
– The DP cycle should be at least one current controller sampling time longer than the
sum of T
i
and T
o
.
The above conditions mean that the smallest common multiple of the current controller
sampling time of all axes operated on the isochronous PROFIBUS and 125 µs is used to set
T
i
, T
o
and T
dp
.
If isochronous operation is not possible due to incorrect sampling time settings, an
appropriate message will be output (A01223, A01224).
Cycle settings for SINAMICS Link
SINAMICS Link permits only three cycle settings:
Table 13- 10 Settings for activated isochronous operation
T
i
[µs] T
o
[µs] T
dp
[µs]
500 500 500
500 1000 1000
1500 1500 1500