Modulo 360 Degrees - Siemens SINUMERIK 840D sl Function Manual

R2: Rotary axes

13.2 Modulo 360 degrees

13.2 Modulo 360 degrees
13.2
Term "modulo 360°"
Rotary axes are frequently programmed in the 360° representation mode. The axis must be
defined as a rotary axis in order to use the modulo feature.
With respect to a rotary axis, the term "modulo" refers to the mapping of the axis position
within the control in the range 0° to 359.999°. With path defaults > 360° (e.g., for incremental
programming using G91), the position is mapped in the range of values 0° to 360° following
conversion within the control. Mapping is performed in JOG and AUTOMATIC modes.
Exception: service display.
In the figure below, the rotary-axis absolute position in the positive direction of rotation is
represented as a spiral. An arrow marks the actual absolute position on this spiral (example:
point C' = 420°). By tracing the arrow back around the circle (position 0° of the spiral and
circle are identical), it is possible to assign an appropriate modulo position within the 360°
range to every absolute position. In the example below, absolute position point C' = 420° is
mapped onto point C = 60° using modulo conversion.
Figure 13-3
Machine-data settings
Machine data can be used to define programming and positioning (MD30310
$MA_ROT_IS_MODULO) as well as the position display (MD30320
$MA_DISPLAY_IS_MODULO) individually in modulo 360° for each rotary axis, depending on
the particular machine requirements.
854
Modulo 360° map
Function Manual, 09/2009, 6FC5397-1BP20-0BA0
Extended Functions