Siemens SINUMERIK Series Function Manual page 687

Modulo position display
MD30320 $MA_DISPLAY_IS_MODULO
= 1
= 0
MD30320 $MA_DISPLAY_IS_MODULO = 1
Note
The modulo 360° position display should always be selected for a modulo axis (MD30310
$MA_ROT_IS_MODULO = 1).
Starting position for the modulo rotary axis
A start position not equal to 0 for the modulo range can be defined:
MD30340 $MA_MODULO_RANGE_START (start position of the modulo range)
For example, this means that a modulo range of -180° to +180° can be achieved by entering
-180 in MD30340.
The default setting of 0 (degrees) defines a modulo range of 0° - 360°.
Figure 12-4
Extended Functions
Function Manual, 03/2013, 6FC5397-1BP40-3BA1
For rotary axes, a position display with "modulo 360°"(one revolution) is often required, i.e.,
with a positive direction of rotation the display is periodically reset within the control to 0.000°
after 359.999° is reached, with a negative direction of rotation the positions are also
displayed in the range 0° to 359.999°.
Absolute-position display would, in the case of a positive direction of rotation, for example,
result in +360° being displayed after one revolution, +720° after two revolutions, etc, in
contrast to the modulo 360° display. In this case, the display range is limited by the control in
accordance with the linear axes.
Starting position of -180° changes the modulo range to -180° to + 180°
R2: Rotary axes
12.2 Modulo 360 degrees
687