5
5.8
Motion Control with PROFIBUS–DP (from SW 3.1)
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SIMODRIVE 611 universal Description of Functions (FBU) – 04.05 Edition
In the ”DP slave 611U”, the speed setpoint is transferred at instant T
O
in each nth DP clock cycle (n = T
MAPC
/T
DP
).
In order to eliminate having to trace the setpoint steps, the speed set-
point can be averaged using an average value filter (P1012.8).
5.8.2
Equidistant DP cycle operation in the positioning mode
The traversing movements can be simultaneously started for several
drives via the clock–synchronous PROFIBUS.
If the traversing blocks have been parameterized the same (travel, ve-
locity, acceleration) in the various drives, then the axes can also move
in synchronism.
Traversing blocks are simultaneously started and synchronous move-
ments of the motion profile are realized precisely in the IPO clock
cycle.
In this case, position differences only result in different following errors
in the axes.
v: Velocity
t: Time
v
t
Axis 2
Interpolation
clock cycle
(IPO clock cycle)
v
t
Axis 1
Fig. 5-27 Example: Simultaneously starting the traversing motion
Average value
generation for n
set
Overview
5 Communications via PROFIBUS DP
08.99
