Rockwell Automation 8520-GUM 9/Series CNC Grinder Operation and Programming Manual Documentation Set - Manual (Page 377)

Axis Motion
Chapter 12
12-5
G02 and G03 establish the circular interpolation mode. In G02 mode, the
grinding wheel moves along a clockwise arc; in G03 mode, the wheel
moves along a counterclockwise arc. Figure 12.3 shows clockwise and
counterclockwise orientation relative to the positive X and Z axes.
Figure 12.3
Circular Interpolation Direction
G03
(counter - clockwise arc)
X
Z
X
Z
G02
(clockwise arc)
12146-I
Your system installer must first define a plane; typically assign the Z and X
axes to the G18 plane. For cylindrical grinders, your system installer
typically makes G18 the default plane that the control assumes when
power is turned on, E-Stop is reset, or the control is reset.
You can perform circular interpolation in the absolute (G90) or incremental
(G91) mode.
Important: S--Curve Acc/Dec mode is not available with circular
interpolation mode.
12.1.3
Circular Interpolation Mode
(G02, G03)