Siemens Sinumerik 840D sl Programming Manual page 453

7.9 Tool length compensation for orientable toolholders (TCARR, TCOABS, TCOFR, TCOFRX, TCOFRY,
Recalculation of tool length compensation (TCOABS) for a frame change
In order to make a new calculation of the tool length compensation when frames are changed,
the tool has to be selected again.
Note
The tool orientation must be manually adapted to the active frame.
When the tool length compensation is calculated, the angle of rotation of the toolholder is
calculated in an intermediate step. With toolholders with two rotary axes, there are generally
two sets of rotation angles, which can be used to adapt the tool orientation to the active
frame; therefore, the rotation angle values stored in the system variables must at least
correspond approximately to the mechanically set rotation angles.
Note
Tool orientation
It is not possible for the control to check whether the rotation angles calculated by means of
the frame orientation are settable on the machine.
If the rotary axes of the toolholder are arranged such that the tool orientation calculated by
means of the frame orientation cannot be reached, then an alarm is output.
The combination of tool precision compensation and the functions for tool length
compensation on movable toolholders is not permissible. If both functions are called
simultaneously, an error message is issued.
The TOFRAME function allows a frame to be defined on the basis of the direction of
orientation of the selected toolholder. For more information please refer to chapter "Frames".
When orientation transformation is active (3, 4 or 5-axis transformation), it is possible to
select a toolholder with an orientation deviating from the zero position without causing output
of an alarm.
Transfer parameter from standard and measuring cycles
For the transfer parameter of standard and measuring cycles, the following defined value
ranges apply.
For angular value, the value range is defined as follows:
• Rotation around 1st geometry axis: -180 degrees to +180 degrees
• Rotation around 2nd geometry axis: -90 degrees to +90 degrees
• Rotation around 3rd geometry axis: -180 degrees to +180 degrees
Refer to Chapter Frames, "Programmable rotation (ROT, AROT, RPL)".
Note
When transferring angular values to a standard or measuring cycle, the following should be
carefully observed:
Values less than the calculation resolution of the NC should be rounded-off to zero!
The calculation resolution of the NC for angular positions is defined in the machine data:
MD10210 $MN_INT_INCR_PER_DEG
Job planning
Programming Manual, 02/2011, 6FC5398-2BP40-1BA0
Tool offsets
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