Siemens SINUMERIK 840D sl Function Manual page 888

Rotary Axes (R2)
Programming rotary axes
● DC application example: the rotary table is required to approach the changeover position
● If DC is programmed with a linear axis, alarm 16800, "DC traverse instruction cannot be
Example:
Programming
POS[C] = AC (7200)
POS[C] = DC(300)
POS[C] = AC (7000)
Note
In this example, it would be advisable to activate the modulo 360º display (MD30320
$MA_DISPLAY_IS_MODULO = 1).
Incremental programming (IC, G91)
Example for positioning axis: POS[axis name] = IC(+/-value)
When programming with incremental dimensions, the rotary axis traverses across the same
path as with the modulo axis. In this case, however, the traversing range is limited by the
software limit switches.
● The value identifies the rotary-axis traversing distance.
● The value's sign unequivocally defines the rotary-axis traversing direction.
Limited traversing range
The traversing range is limited as with linear axes. The range limits are defined by the "plus"
and "minus" software limit switches.
888
in the shortest time (and, therefore, via the shortest path) possible.
used", is output.
The value can be negative and ≥ +/-360°.
Effect
Rotary axis C traverses to position 7200°;
traversing direction depends on the starting position
Rotary axis C approaches "modulo" position 300°
along the shortest path
Thus, C traverses about 60° with a negative direction of rotation
and stops at absolute position 7140°.
Rotary axis C traverses to position 7000° absolutely,
so C traverses about 140° with a negative direction of rotation
Function Manual, 03/2009, 6FC5397-1BP10-4BA0
Extended Functions