Siemens SINUMERIK 840D sl Function Manual page 363

where 0 ≤ k < MD18342 $MN_MM_CEC_MAX_POINTS
The following supplementary conditions apply to interpolation point k:
1. When k = MD18342 - 1
2. When k < MD18342 - 1
3. When k > MD18342 - 1
● Directional compensation ($AN_CEC_DIRECTION[t])
● Table multiplication ($AN_CEC_MULT_BY_TABLE[t])
Extended Functions
Function Manual, 01/2008, 6FC5397-1BP10-3BA0
The compensation value of interpolation point k is used for all positions larger than the
end position (exception: table with modulo functions).
The number of required interpolation points is calculated as follows:
→ The compensation table is fully utilized!
→ The compensation table is not fully utilized; compensation values entered in the table
greater than k have no effect.
→ The compensation table is limited by a control function which reduces the end position.
Compensation values which are greater than k are ignored.
This system variable can be used to define whether the compensation table [t] should
apply to both travel directions of the base axis or only either the positive or negative
direction.
0: Table applies to both directions of travel of the base axis
1: Table applies only to position direction of travel of the base axis
-1: Table applies only to negative direction of travel of the base axis
Possible applications:
Position-dependent backlash compensation can be implemented using two tables, one of
which affects the positive traversing direction, the other of which affects the negative
traversing direction of the same axis.
With the table multiplication function, the compensation values of any table can be
multiplied by those of any other table (or even by the same table). The product is added
as an additional compensation value to the total compensation value of the compensation
table.
Syntax:
$AN_CEC_MULT_BY_TABLE[t
with:
t = index of table 1 of compensation axis
1
t = number of table 2 of compensation axis: Please note that the number and index of the
2
same table are different! In general: Table number = table index + 1
] = t
1 2
Compensations (K3)
5.4 Interpolatory compensation
363