Siemens SINUMERIK 840D sl Function Manual page 266

K3: Compensations
5.4 Interpolatory compensation
The compensation values and additional table parameters are entered in the compensation
tables using special system variables. Data can be loaded in two different ways:
● By starting an NC program with the parameter values.
● By transferring the compensation tables from an external computer to the control.
Note
The respective compensation tables can only be loaded if the corresponding compensation
function is not active for all axes:
● MD32700 $MA_ENC_COMP_ENABLE[<axis>] == 0
● MD32710 $MA_CEC_ENABLE[<axis>] == 0
As the compensation data is also retained when the controls are switched off.
Note
When changing machine data:
● MD18342 $MN_MM_CEC_MAX_POINTS
● MD38000 $MA_MM_ENC_COMP_MAX_POINTS
is formatted during the next system run-up of the static user memory (see Section "S7: Memory
configuration (Page 799)").
Interim value calculation
The traversing distance defined via the start and end position within which compensation is to
apply, is divided into several sub-paths of equal size. The number of sub-paths is defined
depending on the error curve and the desired precision. The positions that limit these sub-
paths are referred to as interpolation points below. An interpolation and a compensation value
must be assigned to each interpolation point. Between two interpolation points, the effective
compensation value is determined by linear interpolation.
①
②
Figure 5-4
266
Compensation values of the compensation axis
Position of basic axis
Intermediate value calculation by linear interpolation
Function Manual, 10/2015, 6FC5397-1BP40-5BA3
Extended Functions