Operational Sequence; 1-Point Measurement And Tool Offset; General Information - Siemens SINUMERIK 840D sl Programming Manual

6.5.2.3

Operational sequence

Position before measuring cycle call
The probe must be positioned opposite the surface to be measured.
Position after end of measuring cycle
On completion of measurement, the probe is positioned facing the measuring surface at
distance _FA.
Notice
Precise measurement is only possible with a probe calibrated under the measurement
conditions, i.e. working plane and measuring velocity are the same for both measurement
and calibration. If the probe is used in the spindle for a powered tool, the spindle orientation
must also be considered. Deviations can cause additional measuring errors.
6.5.3

1-point measurement and tool offset

6.5.3.1

General information

Function
With this measuring cycle and the _MVAR=0 measuring variant, the actual value of a
workpiece is determined with reference to the workpiece zero in the selected measuring
axis.
An offset can also be determined for a tool depending on that. This tool is specified in
_TNUM and _TNAME. The D number and type of offset are specified in coded form in
variable _KNUM.
From measuring cycles SW 6.3, extended tool offset is available. With this function a tool
from a particular stored tool environment _TENV, and additive, setup offsets can be
corrected by specifying the DL number in _DLNUM.
Detailed information on the parameters: see section "Description of the most important
defining parameters".
Empirical values and mean values
An empirical value stored in data block GUD5 in array _EV[ ] can be included in calculation
of the result after measurement is completed. Optionally, averaging is performed over a
number of parts (array _MV[ ]) and the tolerance bands are checked.
Both are activated in _EVNUM (see Section "Description of the most important defining
parameters").
Measuring cycles
Programming Manual, Release 04/2006, 6FC5398-4BP10-0BA0
Measuring Cycles for Turning Machines
6.5 CYCLE974 workpiece: 1-point measurement
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