Siemens SINUMERIK 840D sl Function Manual page 381

Table example
The following example shows the compensation table for sag compensation of axis Y1.
Depending on the position of the Y1 axis, a compensation value is applied to the Z1 axis.
The 1st compensation table (t = 0) is used for this.
%_N_NC_CEC_INI
CHANDATA(1)
$AN_CEC [0,0]
$AN_CEC [0,1]
$AN_CEC [0,2]
:
$AN_CEC [0,100]
$AN_CEC_INPUT_AXIS[0]
$AN_CEC_OUTPUT_AXIS[0]
$AN_CEC_STEP[0]
$AN_CEC_MIN[0]
$AN_CEC_MAX[0]
$AN_CEC_DIRECTION[0]
$AN_CEC_MULT_BY_TABLE[0]
$AN_CEC_IS_MODULO[0]
M17
In this example, the setting for the number of compensation interpolation points must be as
shown below:
MD18342 $MN_MM_CEC_MAX_POINTS [0] ≥ 101(alarm 12400 will otherwise be generated).
The compensation table for this example requires at least 808 bytes of non-volatile NC user
memory.
Table multiplication
With the table compensation function, any table can be multiplied by any other table (i.e.
even by itself). The multiplication link is established using the system variables described
above.
The following example for the compensation of machine foundation sagging illustrates an
application of table multiplication.
On large machines, sagging of the foundation can cause inclination of the whole machine.
For the boring mill in the second diagram below, for example, it is determined that
compensation of the X1 axis is dependent both on the position of the X1 axis itself (since this
determines angle of inclination b) and on the height of the boring mill (i.e. the position of the
Z1 axis).
Extended Functions
Function Manual, 03/2009, 6FC5397-1BP10-4BA0
=0 ; 1st compensation value (≙ interpolation
point 0)
; for Z1: ± 0 µm
=0.01 ; 2nd compensation value (≙ interpolation
point 1)
; for Z1: + 10 µm
=0.012 ; 3rd compensation value (≙ interpolation
point 2)
; for Z1: + 12 µm
=0 ; last compensation value
; (≙interpolation point 101) for Z1: ± 0 µm
=(AX2) ; base axis Y1
=(AX3) ; compensation axis Z1
=8 ; interpolation point distance 8.0 mm
=-400.0 ; compensation starts at
; Y1 = -400 mm
=400.0 ; compensation ends at Y1 = +400 mm
=0 ; table applies in both
; directions of travel of Y1
=0
=0 ; compensation without modulo function
Compensations (K3)
Interpolatory compensation
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