Siemens SINUMERIK 840D sl Function Manual page 848

Rotary Axes (R2)
13.3 Programming rotary axes
● ACP (positive) and ACN (negative) unambiguously define the rotary-axis traversing
● When programming AC exclusively or with G90, the traversing direction depends on the
● Use of ACP and ACN: With asymmetrical workpieces, it must be possible to define the
Example:
C starting position is 0° (see figure below).
①
②
③
④
Figure 13-5
848
direction (irrespective of the actual position).
rotary-axis actual position. If the target position is greater than the actual position, the
axis traverses in the positive direction, otherwise it traverses in the negative direction.
The positioning response can be configured using machine data
MD30455 $MA_MISC_FUNCTION_MASK bit 2:
Bit 2 = 0: with G90, modulo axis positioned as standard using AC
Bit 2 = 1: with G90, modulo axis positioned as standard using DC (shortest path)
traversing direction in order to prevent collisions during rotation.
POS[C] = ACP(100)
POS[C] = ACN(300)
POS[C] = ACP(240)
POS[C] = AC (0)
Examples of absolute programming for modulo axes
Rotary axis C traverses to position 100° in the positive direction of
rotation
C traverses to position 300° in the negative direction of rotation
C traverses to position 240° in the positive direction of rotation
C traverses to position 0° in the negative direction of rotation
Function Manual, 01/2008, 6FC5397-1BP10-3BA0
Extended Functions