Siemens SINUMERIK 840D sl Programming Manual page 313

Caution
Restrictions
With regard to tool motions and collision, a number of restrictions and certain function
exclusions apply, such as:
no tool radius compensation (TRC) may be active with PTP.
With PTPG0 , for active tool radius compensation (TRC), is traversed by CP.
PTP does not permit smooth approach and retraction (SAR).
With PTPG0, CP traversal is used for smooth approach and retraction (SAR).
PTP does not permit cutting cycles (CONTPRON, CONTDCON).
With PTPG0 cutting cycles (CONTPRON, CONTDCON) are traversed by CP.
Chamfer (CHF, CHR) and rounding (RND, RNDM) are ignored.
Compressor is not compatible with PTP and will automatically be deselected in PTP
blocks.
An axis superimposing in the interpolation may not change during the PTP section.
If G643 is specified, an automatic switch to G642 is made after smoothing with axial
accuracy.
For active PTP, the transformation axes cannot be simultaneously positioning axes.
References:
/FB2/ Function Manual Extended Functions; Kinematic Transformation (M1),
"Cartesian PTP travel" section
PTP for TRACON:
PTP can also be used with TRACON, provided the first chained transformation supports
PTP.
Meaning of STAT= and TU= for TRANSMIT
If a rotary axis is to turn by 180 degrees or the contour for CP passes through the pole,
rotary axes depending on the machine data $MC_TRANSMIT_POLE_SIDE_FIX_1/2 [48]
can be turned by -/+ 180 degrees and traversed in clockwise or counter-clockwise direction.
It can also be set whether traversal is to go through the pole or whether rotation around the
pole is to be performed.
Job planning
Programming Manual, 03/2006 Edition, 6FC5398-2BP10-1BA0
Transformations
7.9 Cartesian PTP travel
7-75