12 Functional Descriptions 10.94
12.16.3 Installation
12.16.3.1 Installation without adaptation characteristic
The installation is carried out in two stages. In stage one, the QEC without adaptation
(MD 1804*, bit 6 = 1) is derived.
Two parameters (compensating amplitude and compensation time constant) can be altered.
These two parameters are each increased or decreased until the deviations from the
programmed radius become minimal or have completely disappeared in the circularity test at
the quadrant transition point (figures 2 - 6).
A starting value of a relatively small compensating amplitude
(e.g. MD 1232* = 100) and a time constant of a few position controller cycles
(e.g. MD 1236* = 80) should be defined at the beginning of the measurement.
Changes can most clearly be seen when the circularity test is first carried without QEC
(MD 1804*, bit 6 = 0).
Figure 2 shows typical quadrant transition points without QEC.
Figure 2 Radius deviations at the quadrant transition points without compensation
II
IV
I
Counter 1
Counter 2
Quadrant transition point
III
Setting the compensating amplitude
If the compensating amplitude is too small, the circularity test shows that the radius deviations
from the programmed radius at the quadrant crossover points have insufficient compensation
(see Figure 3).
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SINUMERIK 840C (IA)