Siemens Sinumerik 840D sl Programming Manual page 186

Motion commands
10.6 Circular interpolation
Meaning
G2:
G3:
X... Y... Z... :
CR=... :
Note
You don't need to specify the center point with this procedure. Full circles (traversing angle
360°) are not programmed with CR=, but via the circle end position and interpolation
parameters.
Examples
Example 1: Milling
Program code
N10 G0 X67.5 Y80.511
N20 G3 X17.203 Y38.029 CR=34.913 F500
...
186
Circular interpolation clockwise
Circular interpolation counter-clockwise
End point in Cartesian coordinates. These specifications depend on the
travel commands G90/G91 or ...=AC(...)/...=IC(..)
Circle radius
The meanings are as follows:
CR=+...: Angle less than or equal to 180°
CR=–...: Angle greater than 180°
Y
CR = +...
17.203
67.500
CR = -...
X
Programming Manual, 01/2015, 6FC5398-1BP40-5BA2
Fundamentals