Hexagon Leica Nova MS60, User Manual

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Therefore, the overall pointing accuracy of the determined point location can
be lower than the given angular accuracy and the ATRplus accuracy.
The following paragraphs provide a short overview of these influencing factors
and their possible intensities.
Angular accuracy
The accuracy of angular measurements depends on the instrument type. The
angular accuracy for total stations is typically in the range from 0.5
²
to 5
²
. The
resulting error depends on the measurement distance.
The table shows possible deviations for typical angular accuracies. 1
² and 3 ²
are examples.
Angular accuracy
Possible deviation
*
at 100 m distance
1
² ~
0.5 mm
3
² ~
1.5 mm
*
Orthogonal to the line of sight.
☞
Refer to the data sheet of the respective instrument model for
information about the angular accuracy.
EDM accuracy
The distance measurement accuracy consists of two parts: a fixed value and a
distance-dependent value (ppm-value).
Example: "Single measurements: 1 mm + 1.5 ppm"
The EDM accuracies for prism and reflectorless measurements can differ. Addi-
tionally, the accuracies can differ depending on the used technologies.
☞
Refer to the appropriate data sheet for information about the EDM
accuracy.
ATRplus accuracy
Automatic target aiming accuracies, like those of the ATRplus, are in general
the same as the stated angular accuracy. Therefore these accuracies are also
distance-dependent parameters.
External impacts, like heat shimmer, rain (prism surface covered by rain drops),
fog, dust, strong background lights, dirty targets, alignment of the targets etc.
can have a significant influence on the automated target. In addition, the
selected EDM mode affects the ATRplus performance. Under good environ-
mental conditions and with a clean, properly aligned target the accuracy of the
automated target aiming is equivalent to the manual target aiming (presumed
valid calibration values).
Type and centring accuracy of the prism
The prism centring accuracy depends mainly on the used prism type, for
example:
Prism type Centring accuracy
Leica GPR1 Circular prism 1.0 mm
Leica GPH1P Precision circular prism 0.3 mm
Leica GRZ122 360° prism 2.0 mm
Leica GRZ4 360° prism 5.0 mm
80 Technical Data