Siemens SINUMERIK 828D Programming Manual page 371

Direction of rotation
The following is defined as the positive direction of rotation: The view in the direction of the
positive coordinate axis and clockwise rotation.
Order of rotation
Up to 3 geometry axes can be rotated simultaneously in one NC block.
The sequence in which the rotations are to be executed is defined using machine data
(MD10600 $MN_FRAME_ANGLE_INPUT_MODE):
● RPY notation: Z, Y', X''
● Euler angles: Z, X', Z''
Fundamentals
Programming Manual, 07/2010, 6FC5398-1BP40-0BA0
or
Coordinate transformations (frames)
12.4 Programmable rotation (ROT, AROT, RPL)
371