HEIDENHAIN ND 930 - Manual (Page 42)

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Multipoint Axis Error Compensation
If you want to use the multipoint axis error compen-
sation feature, you must
• activate this feature with operating parameter P40
(see "Operating Parameters")
• traverse the reference marks after switching on the
display unit.
• enter compensation value table
Entries in the compensation value table
• Axis to be compensated: X, Z or Zo
(Zo only with ND 970)
• Axis with error: X, Z or Zo
(Zo only with ND 970)
• Datum for the axis to be corrected:
Here you enter the point starting at which the axis with
error is to be corrected. This point indicates the absolute
distance to the reference point.
Do not change the datum point after measuring the
axis error and before entering the axis error into the
compensation table.
• Spacing of the compensation points
The spacing of the compensation points is expressed as
2 x
[µm].
Enter the value of the exponent x into the compensation
value table.
Minimum input value: 6 (= 0.064 mm)
Maximum input value: 20 (= 1052.672 mm)
Example: 600 mm traverse and 35 compensation points:
results in 17.143 mm spacing between points.
Nearest power of two: 2
14 [µm] = 16.384 mm
Entry in compensation value table: 14
• Compensation value
You enter the measured compensation value (in
millimeters) for the displayed compensation point.
Compensation point 0 always has the value 0 and
cannot be changed.
Multipoint Axis Error Compensation
Your machine may have a non-linear axis error due to factors
such as axis sag or drivescrew errors. Such deviations are
usually measured with a comparator measuring system. This
allows you to determine, for example, the screw pitch error
[X = F(X)] for the X axis. The display value is then automatically
compensated by the error associated with the current position.
An axis can only be corrected in relation to one axis causing
the error. You can create a compensation value table for each
axis, with each table containing 64 compensation values. The
tables can then be accessed with the MOD key and CODE
NUMBER.