Siemens SINUMERIK 840D sl Function Manual page 645

8.4.3.2 Measurement of an angle (measurement type 4, 5, 6, 7)
Measurement of a corner C1 - C4 ($AC_MEAS_TYPE = 4, 5, 6, 7)
A corner is uniquely defined by approaching four measuring points P1 to P4. Three
measurement points suffice in the case of known angles of intersection ϕ.
If the angle of intersection ϕ and the workpiece position angle α are known, two
measurement points P1 and P3 suffice.
Figure 8-7
Figure 8-8
The values of the following variables are evaluated for measurement types 4 to 7:
Input variable
$AC_MEAS_VALID
$AA_MEAS_POINT1[axis]
$AA_MEAS_POINT2[axis]
$AA_MEAS_POINT3[axis]
Extended Functions
Function Manual, 03/2009, 6FC5397-1BP10-4BA0
Corner C1, corner C2
Corner C3, corner C4
Setting zeros, workpiece measuring and tool measuring
Description
Validity bits for input variables
Measuring point 1
Measuring point 2 irrelevant for $AC_MEAS_WP_SETANGLE
Measuring point 3
Measurement (M5)
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