Siemens SINUMERIK 840D sl Programming Manual page 37

Rotary motion around the coordinate axes X, Y and Z are designated A, B and C. The direction
of rotation is obtained from the direction of the rotary motion when looking in the positive
direction of the coordinate axis:
Direction of the rotary motion
clockwise
counter-clockwise
X, Y, Z
A, B, C
NC programming
Programming Manual, 12/2019, 6FC5398-2EP40-0BA0
Vertical coordinate axes arranged on top of one another
Rotary axes, rotating around X, Y, Z
2.1 Fundamental Geometrical Principles
Direction of rotation
positive
negative
Fundamentals
37