Siemens SINUMERIK 840D sl Function Manual page 357

Smooth the compensation value
To prevent overloading of the machine or tripping of monitoring functions in response to step
changes in the above parameter settings, the compensation values are distributed among
several IPO cycles by an internal control function as soon as they exceed the maximum
compensation value specified for each cycle in the following machine data:
MD32760 $MA_COMP_ADD_VELO_FACTOR
(velocity violation caused by compensation)
Position display
The normal actual-value and setpoint position displays ignore the compensation values and
show the position values of an ideal machine.
Display the compensation values
The total compensation value calculated from the temperature and sag compensation
functions belonging to the current actual position is output in the "Service axes" display in the
"Diagnosis" operating area.
Determine example of error curve
Commissioning of temperature compensation is described below using the example of a Z
axis on a lathe.
In order to determine the temperature-dependent error characteristic of the Z axis, proceed
as follows:
● Constant heating by traversing the axis across the whole Z axis traversing range (in the
● Measuring the axis position in increments of 100 mm
● Measuring the actual temperature at the leadscrew
● Executing a traversing measuring cycle every 20 minutes
The mathematical and technological relationship and the resulting parameters for
temperature compensation are derived from the recorded data. The calculated deviation
errors for a specific temperature, which refer to the actual position of the Z axis displayed by
the NC, are represented in graphic form in the diagram below.
Extended Functions
Function Manual, 03/2009, 6FC5397-1BP10-4BA0
example: from 500 mm to 1500 mm)
Compensations (K3)
Temperature compensation
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