Siemens SINUMERIK 840D sl Function Manual page 358

Compensations (K3)
5.4 Interpolatory compensation
Figure 5-9
Depending on the requirement, several compensation relations can be defined for one axis.
The total compensation value results from the sum of all the compensation values of this
axis.
Setting options
The many ways in which the compensation value for sag compensation can be
produced/influenced are listed below (see diagram below).
1. An axis can be defined as the input variable (base axis) for several compensation tables
(settable via system variables).
2. An axis can be defined as the recipient of the output variable (compensation axis) of
several compensation tables (settable via system variable). The total compensation value
is derived from the sum of the individual compensation values.
3. An axis can be both a base axis and a compensation axis at any one time. The
programmed (required) position setpoint is always used to calculate the compensation
values.
4. The scope of action of the compensation (starting and end position of the base axis) and
the distance between the interpolation points can be defined for every compensation
table (settable via system variables).
5. Compensation can be direction-dependent (settable via system variables).
6. Every compensation table has a modulo function for cyclic evaluation (settable via
system variables).
358
Example of sag caused by own weight
The following definitions apply for the maximum number of possible compensation tables:
– Total maximum number of tables available for all axes:
2 * maximum number of axes of system
– Maximum number of tables configured for one particular compensation axis:
1 * maximum number of axes of system
Function Manual, 01/2008, 6FC5397-1BP10-3BA0
Extended Functions