Commissioning - Siemens SINUMERIK Series Function Manual

K3: Compensations
4.4 Interpolatory compensation
Direction-dependent leadscrew error compensation
For the "direction-dependent leadscrew error compensation" ("direction-dependent LEC" or
also "Bidirectional LEC") , two compensation tables are used for each axis. One
compensation table for the positive and one compensation table for the negative traversing
direction. The deviation at the particular compensation point is entered as difference
between the ideal setpoint and measured actual value in the compensation tables. The
control automatically calculates compensation values of intermediate values using linear
interpolation.
Preconditions / activation
The "direction-dependent LEC" is implemented in the SINUMERIK control as a special case
of "sag compensation". This is the reason that the preconditions and conditions of "sag
compensation" apply (see "Compensation of sag and angularity errors (Page 243)").
The activation of the compensation can be checked using a reference measurement, e.g.
using the laser interferometer or in the simplest case, using the service display of the
particular axis.
Note
If the "direction-dependent LEC" is used in parallel to the sag compensation and
compensation of the angularity, then the secondary conditions of these functions must be
taken into consideration together, e.g. the assignment of tables <t> to the particular function.
4.4.4.2

Commissioning

Measuring the error or compensation values
When commissioning the "direction-dependent LEC" - just the same as when commissioning
the "direction-dependent LEC" - direction-dependent error curves for each axis are
determined using a suitable measuring device (e.g. laser interferometer) (see Section
"Compensation of leadscrew errors and measuring system errors (Page 238)"). A part
program with measurement points and wait times should be generated in order to perform
the measurement (see Section "Example (Page 264)"): Program
"BI_SSFK_MESS_AX1_X.MPF").
Because the various measuring devices offer different support options for the practical
implementation in conjunction with a SINUMERIK control, this process is only generally
described in the following referred to a control.
Note
The measurement for determining the leadscrew error should only be carried out during the
first commissioning if, in the machine data, the traversing directions of the axes in relation to
the machine coordinate system have been correctly set.
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Function Manual, 03/2013, 6FC5397-1BP40-3BA1
Extended Functions