Approaching And Leaving Contour (Norm, Kont, Kontc, Kontt) - Siemens Sinumerik 840D sl Programming Manual

Tool radius compensation

11.2 Approaching and leaving contour (NORM, KONT, KONTC, KONTT)

Circular interpolation produces spiral movements.
Changing the tool radius
The change can be made, e.g. using system variables. The sequence is the same as when
changing the tool offset data set (D...).
Note
The modified values only take effect the next time T or D is programmed. The change only
applies with effect from the next block.
Compensation mode
Compensation mode may only be interrupted by a certain number of consecutive blocks or M
functions which do not contain drive commands or positional data in the compensation plane.
Note
The number of consecutive blocks or M commands can be set in a machine data item (see
machine manufacturer's specifications).
Note
A block with a path distance of zero also counts as an interruption!
11.2 Approaching and leaving contour (NORM, KONT, KONTC, KONTT)
Requirement
The KONTC and KONTT commands will only be available if the "Polynomial interpolation" option
has been enabled in the control.
Function
If tool radius compensation is active (G41/G42), the NORM, KONT, KONTC or KONTT command
can be used to adapt the tool's approach and retract paths to the required contour profile or
blank form.
KONTC or KONTT ensure observance of the continuity conditions in all three axes. It is,
therefore, permissible to program a path component perpendicular to the offset plane
simultaneously.
Syntax
G41/G42 NORM/KONT/KONTC/KONTT X... Y... Z...
...
G40 X... Y... Z...
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Programming Manual, 01/2015, 6FC5398-1BP40-5BA2
Fundamentals