Siemens SINUMERIK 840D sl Function Manual page 282

K3: Compensations
5.4 Interpolatory compensation
Compensation table 2 (index = 1)
● Basic axis: Z1
● Compensation axis: X1
● Compensation values: Reaction of axis Z1 on axis X1 (linear).
For compensation relationship 1 (index = 0), multiplication by the compensation values of the
compensation relationship 2 must be set:
$AN_CEC_MULT_BY_TABLE[ 0 ] = 2
Example 3: 2-dimensional array of compensation values
For flat-bed machines, the use case often arises in practice in which the sag compensation
values of the Z-axis depend on the axis positions of the X and Y axes. Under these conditions,
organization of the compensation values in a 2-dimensional array is convenient. The
interpolation points with the relevant compensation values are positioned at the intersections
of the grid (X-Y plane). Compensation values between these interpolation points are
interpolated linearly by the control.
The following example explains in more detail how sag and angularity compensation can be
implemented by a grid of 4 x 5 (rows x columns) in size. The size of the whole grid is
2000 x 900 mm
X axis and 300 mm along the Y axis.
Note
The following interdependencies apply to the maximum dimension of the grid (number of rows
and columns):
● The number of rows depends on the number of axes in the system (depending on the NCU
type).
● The number of columns is dependent on the maximum number of values which can be
entered in a compensation table (up to a total of 2000 values).
The number of rows and columns is set in the following machine data:
MD18342 $_MN_MM_CEC_MAX_POINTS (maximum number of interpolation points for sag
compensation)
Memory-configuring machine data
Settings made to the MD18342 machine data cause the non-volatile NC user memory to be
automatically re-allocated on system power-on. All the user data in the NC user memory (e.g.
drive and HMI machine data, tool offsets, part programs, etc.) is deleted.
Save the user data before setting the machine data.
282
. The compensation values are each measured in steps of 500 mm along the
2
CAUTION
Function Manual, 10/2015, 6FC5397-1BP40-5BA3
Extended Functions