Probe, Calibration Body, Calibration Tool; Measuring Workpieces On Milling Machines, Machining Centers - Siemens SINUMERIK 840D sl Programming Manual

2.7

Probe, calibration body, calibration tool

2.7.1

Measuring workpieces on milling machines, machining centers

Probe calibration
All probes must be mechanically correctly adjusted before use. The switching directions must
be calibrated before they are used in the measuring cycles for first-time. This also applies when
changing the stylus tip of the probe.
When being calibrated, the trigger points (switching points), position deviation (skew), and
active ball radius of the workpiece probe are determined and entered into the data fields of the
general setting data SD 54600 $SNS_MEA_WP_BALL_DIAM . There are 40 data fields.
Calibration can be realized in a calibration ring (known bore), on a calibration ball or on
workpiece surfaces, which have an appropriate geometrical precision and low surface
roughness.
Use the same measuring velocity for calibrating and measuring. This applies in particular to
the feedrate overide. If, in MD51740 $MNS_MEA_FUNCTION_MASK, bit 6 is set =1, then
100% feed rate override traversing velocity is used for the measuring blocks (MEAS) in the
measuring cycles if the feedrate override is set > 0. If calibration is performed more than once
on a calibration data set, the same measuring velocity must be set, otherwise the previous
calibration will be declared as being invalid.
Measuring cycle CYCLE976 with different measuring variants is available to calibrate the
probe.
Measuring
All probe types can be used in conjunction with a spindle capable of positioning. This ensures
that all milling measuring variants can be applied.
When positioning the probe, the measuring cycles always refer to the active master spindle.
If several spindles exist, then this condition must be satisfied by the user. During the program
runtime, this is possible using the SETMS NC command.
Example: SETMS(3); the third spindle is defined as master spindle.
If probes are used in conjunction with spindles that are not capable of positioning, restrictions
are obtained regarding the measuring variants and probe types. For illegal measuring variants,
alarms can be displayed during the cycle time.
At the calibration and measurement instant, the user must guarantee an identical orientation
(spindle position) of the probe, for example by clamping or indexing.
If probes are fixed in a system, restrictions are obtained regarding the measuring variants and
probe types. For illegal measuring variants, alarms can be displayed during the cycle time.
When the probe is mounted in the machine at a fixed position, a mechanical offset can exist
in the three geometry axes between the center point of the probe ball (tool tip) and the tool
reference point.
Measuring cycles
Programming Manual, 12/2017, 6FC5398-4BP40-6BA1
2.7 Probe, calibration body, calibration tool
Description
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