Further Optimization And Intervention Options - Siemens SINUMERIK 840D sl Function Manual

5.6.3.5

Further optimization and intervention options

Optimization options
In cases where the results of the circularity test do not meet the required accuracy
standards, the system can be further improved by selective changes to QEC system
variables. Several ways of optimizing the neural QEC are explained here.
Alteration of coarse and fine quantization
The input value is quantized by the two variables "coarse quantization" and "fine
quantization".
A high value for the fine quantization causes a "similar" output signal to be obtained for
adjacent intervals of the input signal, allowing, for example, measuring errors which occur
only at a particular acceleration rate to be identified.
With a low fine quantization, highly fluctuating characteristics are reproduced better.
For the neural friction compensation, it is necessary to make use of the largest error
tolerance by setting a high fine quantization ($AA_QEC_FINE_STEPS in the region of 5 to
10).
Directional compensation
Direction-dependent friction compensation must be used in cases where compensation is
not applied equally on opposing quadrants when compensation values are being injected
independently of direction (see diagram below).
The directional injection is activated via the system variable $AA_QEC_DIRECTIONAL =
TRUE.
Here, the following aspects must be observed:
Extended Functions
Function Manual, 09/2009, 6FC5397-1BP20-0BA0
5.6 Friction compensation (quadrant error compensation)
K3: Compensation
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