Lenze E84DSxxx - Manual (Page 264)

7 Technology applications
7.3 TA "Switch-off positioning"
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Lenze · 8400 protec StateLine · Reference manual · DMS 4.2 EN · 03/2013 · TD05
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System limits and exclusion criteria
They result from the non-compliance with the decision criteria.
Compared to systems with speed feedback, the positioning and repeat accuracy is reduced.
Due to the mechanical hardware limit switches, this concept is only applicable for systems with only
a few fixed positions. Changing the target position during the operation or the teaching is not
possible.
If necessary, additional functions like manual jog or homing must be realised externally, e.g. via a
control.
As the HighLine version does not meet safety-related functions except STO (Safe Torque Off), you
must observe that all safety-related aspects are realised by the plant constructor.
Especially in the case of an outdoor use or in wet areas, you must consider the corresponding
discharge currents when operated with a fault current circuit breaker.
Highly dynamic applications and jerk-free traversing profiles require table positioning or sequential
positioning control (with HighLine).
Related topics:
 Commissioning of the "Switch-off positioning" technology application ( 54)
Positioning accuracy at the motor
shaft
The positioning accuracy of the load
depends e.g. on the selected
mechanics by clearance and friction
and must be determined
individually.
The ideal case is 5-10° at the motor
shaft.
Consider the influence of the motor
temperature.
In the case of a constant load, you can
assume a good repeat accuracy
during positioning. In the case of
variable loads, you must take
significant deviations into account.
5-10° at the motor shaft. As the
positioning is executed in a creeping
speed, a good repeat accuracy is
reached even for variable loads.
Speed setting range 1 : 50, based on 50Hz and M
n
1 : 50, based on 50Hz and M
n
Typical applications Switch-off positioning with constant
load, e.g. travelling drive, roll-up
door.
Switch-off positioning with variable
load, e.g. travelling drive, conveying
belt, hoists approaching a stop
position
Criteria Switch-off positioning with constant
load
Switch-off positioning with variable
load