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14. COORDINATE MEASUREMENT
By performing coordinate measurements it is possible to find the 3-dimensional
coordinates of the target based on station point coordinates, instrument height,
target height, and azimuth angles of the backsight station which are entered in
advance.
• EDM setting can be done in coordinate measurement menu.
Setting items: "33.2 EDM Settings"
PROCEDURE 3-D Coordinate Measurement
The coordinate values of the target can be found by measuring the target based
on the settings of the instrument station and backsight station.
The coordinate values of the target are calculated using the following formulae.
N1 Coordinate = N0 + S x sinZ x cosAz
E1 Coordinate = E0 + S x sinZ x sinAz
Z1 Coordinate = Z0 + S x cosZ + ih - th
N0: Station point N coordinate S: Slope distance ih: Instrument height
E0: Station point E coordinate
Z: Zenith angle
th: Target height
Z0: Station point Z coordinate
Az: Direction angle
Z (zenith angle) is calculated as 360° -Z when the telescope is in the face left
position.