Siemens SINUMERIK 840D sl Function Manual page 575

Figure 8-23
Settings in the system data:
Left-hand tool: Approach direction +x and tool orientation -y
System variable
$AC_MEAS_TOOL_MASK = 0x80
$AC_MEAS_DIR_APPROACH = 0
Right-hand tool: Approach direction -x and tool orientation -y
$AC_MEAS_TOOL_MASK = 0x80
$AC_MEAS_DIR_APPROACH = 1
For both tools
$AC_MEAS_Px_COORD = 0
$AC_MEAS_SET_COORD = 0
Extended Functions
Function Manual, 10/2015, 6FC5397-1BP40-5BA3
8.5 Setting zeros, workpiece measuring and tool measuring
Two milling tools each with its own reference point
Meaning
Tool position in -y direction
Approach direction +x
Tool position in -y direction
Approach direction -x
Coordinate system of x-th measuring point =
WCS (default setting)
Coordinate system of the setpoint =
WCS (default setting)
M5: Measurement
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