Siemens SINUMERIK 840D sl Programming Manual page 192

Fundamentals
2.9 Motion commands
X... Y... Z... :
CR=±... :
Examples
Example 1: Milling
Program code
N10 G0 X67.5 Y80.511
N20 G3 X17.203 Y38.029 CR=34.913 F500
...
192
Circle end point in Cartesian coordinates.
Depending on the currently valid dimensional notation setting G90/G91
or ...=AC(...) / ...=IC(...), the end point coordinates are interpreted
either in the absolute dimension or in the incremental dimension.
Circle radius
The sign indicates whether the traversing angle is to be greater than or less
than 180°. A positive sign can be omitted.
CR=+... : Traversing angle ≤ 180°
CR=-... : Traversing angle > 180°
Note
There is no practical limitation on the maximum size of the programmable
radius.
Programming Manual, 12/2019, 6FC5398-2EP40-0BA0
NC programming