HEIDENHAIN TNC 640 (34059x-02) ISO programming - Manual (Page 392)

Programming: Multiple Axis Machining
12.4 Miscellaneous functions for rotary axes
12
392
TNC 640 | User's Manual for DIN/ISO Programming | 5/2013
Shortest-path traverse of rotary axes: M126
Standard behavior
The behavior of the TNC when positioning the rotary
axes depends on the machine tool. Refer to your
machine manual.
The standard behavior of the TNC while positioning rotary axes
whose display has been reduced to values less than 360° is
dependent on machine parameter
shortestDistance (300401).
This machine parameter defines whether the TNC should consider
the difference between nominal and actual position, or whether it
should always (even without M126) choose the shortest path to the
programmed position. Examples:
Actual position Nominal position Traverse
350° 10° –340°
10° 340° +330°
Behavior with M126
With M126, the TNC will move the axis on the shorter path of
traverse for rotary axes whose display is reduced to values less
than 360°. Examples:
Actual position Nominal position Traverse
350° 10° +20°
10° 340° –30°
Effect
M126 becomes effective at the start of block.
To cancel M126, enter M127. At the end of program, M126 is
automatically canceled.