The Rotary Axis - Siemens SIMATIC S5 Manual

2.5.3.3

The Rotary Axis

A rotary axis or closed axis is an axis without restrictions in terms of the traversing range. This
might be, e.g.
a round table (e.g. 360 degree divisions),
continuous tape which can be divided into metric units or
a tape winder.
With a rotary axis, the start of the range and end of the range are physically the same point on
the axis (closed axis). If degrees are used as the dimension, the traversing range is not limited to
The traversing range must be a whole multiple of the positioning resolution. If the reference point
must be reproducible, the following must apply:
Traversing range = whole multiple of re~~~~~~n
360° / 0°
180"
Fig. 2/9 The rotary axis and range limits
The absolute traversing range of a rotary axis is between the start of the range and the end of the
range. If the actual position value exceeds the end of the range, the actual value indication is
automatically set again to the coordinate of the start of the range.
Absolute targets must remain within the specified traversing range. If, however, a traversing
movement is specified relative to the current actual value (e.g. 500 degrees forward), distances
greater than the traversing range can also be travelled.
With the rotary axis, there is no limitation of the traversing range by software limit switches. The
digital inputs of the hardware limit switches are, however, evaluated and can be used to limit the
traversing range to values less than 1 revolution or as additional safety switches.
Start of range
and
end of range
Machine Data and their Structure
Start of range
and
end of range
O m / 10 m
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