Siemens SINUMERIK 828D Programming Manual page 217

Note
and
G2
The default settings
end point.
Per default, the center point coordinates
relation to the circle starting point.
You can program the absolute center point dimensions in relation to the workpiece zero
block-by-block with:
0 can be omitted, but the associated second parameter must always be specified.
Examples
Example 1: Milling
Center point data using incremental dimensions
N10 G0 X67.5 Y80.211
N20 G3 X17.203 Y38.029 I–17.5 J–30.211 F500
Center point data using absolute dimensions
N10 G0 X67.5 Y80.211
N20 G3 X17.203 Y38.029 I=AC(50) J=AC(50)
Fundamentals
Programming Manual, 07/2010, 6FC5398-1BP40-0BA0
are modal.
G3
/ absolute and incremental dimensions are only valid for the circle
G90 G91
,
I=AC(...) J=AC(...)
, , are entered in incremental dimensions in
I J K
, . One interpolation parameter
K=AC(...)
Motion commands
9.6 Circular interpolation
, , with value
I J K
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