Siemens SINUMERIK 840D sl Function Manual page 740

R2: Rotary axes
13.3 Programming rotary axes
①
②
③
④
Figure 13-6
Block-search response
After block search with calculation, the collected search run positions can be read by modulo,
converted using the system variable $AC_RETPOINT[<axis>].
Supplementary conditions for ASUB after block search with calculation
In this instance, as well as with the cross-channel block-search tool SERUPRO, the modulo
conversion simulated in the block search must be performed in the part program.
Incremental programming (IC, G91)
Example for positioning axis: POS[axis name] = IC(+/-value)
● The value identifies the rotary-axis traversing distance. The value can be negative and ≥
+/-360°.
● The value's sign unequivocally defines the rotary-axis traversing direction.
● Application example: milling a spiral groove across several revolutions
Example
Programming
POS[C]=IC(720)
POS[C]=IC(-180)
740
POS[C] = DC(100); Traverse by shortest path to position 100°
POS[C] = DC(300); Traverse by shortest path to position 300°
POS[C] = DC(240); Traverse by shortest path to position 240°
POS[C] = DC(60); Traverse by shortest path to position 60°
; in positive direction of rotation
Absolute programming with shortest path for modulo rotary axes
Effect
C axis traverses to 720° incrementally in the positive direction
(two revolutions)
C axis traverses to 180° incrementally in the negative direction
Function Manual, 10/2015, 6FC5397-1BP40-5BA3
Extended Functions