Siemens SINUMERIK 828D Programming Manual page 493

● Without preprocessing stop in the part program via system variables:
Note
If no tolerance values have been programmed, the $P variables will return the value "-1".
Job planning
Programming Manual, 07/2010, 6FC5398-2BP40-0BA0
8.8 Programmable contour/orientation tolerance (CTOL, OTOL, ATOL)
$P_CTOL Programmed contour tolerance
$P_OTOL Programmed orientation tolerance
$PA_ATOL Programmed axis tolerance
Path traversing behavior
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