Functional Description; Function - Siemens SINUMERIK 840D sl Function Manual

15.2

Functional description

15.2.1

Function

Block search with calculation on contour
To be able to resume interrupted machining at a specific point in a part program, a block
search can be carried out using the "Block search with calculation on contour" standard
function. However, detailed knowledge of the part program is required to be able to enter the
block number of the part program block required for the block search (i.e. the number of the
block the search needs to locate).
Continue machining - Retrace support
The "Continue machining - Retrace support" technological function supports the continuation
of the machining operation by means of an implicit block search with calculation on the
contour without the machine operator needing to know the part program block required.
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).
Special Functions
Function Manual, 09/2011, 6FC5397-2BP40-2BA0
TE7: Continue machining - retrace support
15.2 Functional description
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