Siemens SINUMERIK 840D sl Function Manual page 325

5. The optimized parameter values are applied graphically, e.g. amplitude = f(a
6. Setting of the next acceleration a
Performing the circularity test without friction compensation
A circularity test without friction compensation should be performed to determine the initial
quality of the circular contour at the quadrant transitions. To do this, switch off the friction
compensation temporarily:
MD32500 FRICT_COMP_ENABLE[ <axis> ] = 0
The following figure shows a typical example of quadrant transitions without friction
compensation:
Figure 5-16
The friction compensation must then be activated again:
MD32500 FRICT_COMP_ENABLE[ <axis> ] = 1
Performing circularity test with friction compensation
It is recommended that a small amplitude value and a decay time of just a few position control
cycles be set as initial values for the velocity setpoint pulse, e.g.:
● MD32520 $MA_FRICT_COMP_CONST_MAX[ <axis> ] = 10 [mm/min]
● MD32540 $FRICT_COMP_TIME[ <axis> ] = 0.008 [s]
The circularity test performed with these values provides an initial assessment of the friction
compensation.
Amplitude too small
Too small an amplitude value (MD32520) is revealed in the circularity test by insufficient
compensation of the contour deviations at the quadrant transitions.
Extended Functions
Function Manual, 10/2015, 6FC5397-1BP40-5BA3
5.7 Friction compensation with a constant compensation value
Quadrant transitions without friction compensation
and continuation with point 2.
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K3: Compensations
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