Siemens SINUMERIK 840D sl Function Manual page 701

Continue machining might be required for example in a laser cutting application if the laser is
lost during the machining operation and machining needs to resume at the point at which it
was interrupted.
RESU supports the machining continuation via the following automatically running sub-
functions:
● Function-specific reverse travel along the contour to the required program continuation point
● Automatic identification of the part program block associated with the program continuation
point
● Block search with calculation on the contour for the part program block identified
● Repositioning on the contour at the program continuation point
● Continuation of part program machining
To approach the required program continuation point exactly, it is possible to switch several
times between reverse and forward travel along the contour during the continue machining
process.
Retraceable contour areas
RESU is activated via programming of the function-specific part program command
CC_PREPRE (1). Only the contour range lying between the RESU start (CC_PREPRE(1))
and the interruption point (NC stop) is retraceable in the sense of "continue machining".
Once RESU has been launched, all part program blocks in which traversing movements are
programmed are logged by RESU for possible subsequent reverse travel. Contour ranges for
which continuing machining is irrelevant can be excluded from the log using RESU stop
CC_PREPRE (0).
Contour ranges which are not logged are bridged by straight lines between the starting and
end points during reverse/forward travel.
Figure 19-2
Special functions
Function Manual, 01/2015, 6FC5397-2BP40-5BA2
TE7: Continue machining at the contour (retrace support) - 840D sl only
Retraceable contour range
19.2 Function description
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