Siemens SINUMERIK 840D sl Function Manual page 982

Indexing Axes (T1)
Equidistant index intervals
Modulo rotary axis
Activating
The functions with equi-distant indexing for an axis (linear axis, modulo rotary axis or rotary
axis) is activated in the following settings
MD30500 $MA_INDEX_AX_ASSIGN_POS_TAB[axis] = 3
16.5.2 Hirth tooth system
Function
With Hirth tooth systems, positions of rotation on a rotary axis are usually interlocked using a
latch or other toothed wheel via a linear axis. The interlock should only be activated when an
indexing position has been reached precisely. The distance between the indexing positions
is the same (equidistant) across the entire circumference.
Requirements
The rotary axis must be an indexing axis. The axis must be referenced.
References:
/FB1/ Function Manual, Basic Functions; Reference Point Approach (R1)
982
Function Manual, 03/2009, 6FC5397-1BP10-4BA0
Extended Functions