Siemens SINUMERIK Series Function Manual page 517

Two milling tools each with their own reference point with tool counter-orientation in the approach
direction
Two milling tools each with their own reference point with a tool orientation in the approach
direction
In the present layout, the tool position $AC_MEAS_TOOL_MASK and approach direction to
the workpiece $AC_MEAS_DIR_APPROACH must be set as follows:
Left-hand tool: Approach direction and tool orientation +x
System variable
$AC_MEAS_TOOL_MASK = 0x2
$AC_MEAS_DIR_APPROACH = 0
Right-hand tool: Approach direction and tool orientation -x
$AC_MEAS_TOOL_MASK = 0x40
$AC_MEAS_DIR_APPROACH = 1
For both tools
$AC_MEAS_Px_COORD = 1
$AC_MEAS_SET_COORD = 1
Extended Functions
Function Manual, 03/2013, 6FC5397-1BP40-3BA1
7.5 Setting zeros, workpiece measuring and tool measuring
Meaning
Tool position in x direction (G19)
Approach direction +x
Tool position in the -x direction
Approach direction -x
Coordinate system of x-th measuring point = BCS
Coordinate system of the setpoint = BCS
M5: Measurement
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