Siemens SINUMERIK 840D sl Programming Manual page 214

Motion commands
9.6 Circular interpolation
Example 2: Turning
Center point data using incremental dimensions
N120 G0 X12 Z0
N125 G1 X40 Z-25 F0.2
N130 G3 X70 Z-75 I-3.335 K-29.25
N135 G1 Z-95
Center point data using absolute dimensions
N120 G0 X12 Z0
N125 G1 X40 Z-25 F0.2
N130 G3 X70 Z-75 I=AC(33.33) K=AC(-54.25)
N135 G1 Z-95
Further information
Indication of working plane
214
Programming Manual, 09/2011, 6FC5398-1BP40-2BA0
Fundamentals