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20.OFFSET MEASUREMENT
Offset measurements are performed in order to find a point where a target cannot be installed directly or to find
the distance and angle to a point which cannot be sighted.
• It is possible to find the distance and angle to a point you wish to measure (target point) by installing the target
at a location (offset point) a little distance from the target point and measuring the distance and angle from
the survey point to the offset point.
• The target point can be found in the five ways explained below.
Finding it by entering the horizontal distance from the target point to the offset point.
• When the offset point is positioned to the left or right of the target point, make sure the angle formed by lines
connecting the offset point to the target point and to the instrument station is almost 90°.
• When the offset point is positioned in front of or behind the target point, install the offset point on a line linking
the instrument station with the target point.
PROCEDURE
1. Set the offset point close to the target point and measure
the distance between them, then set up a prism on the
offset point.
2. Enter the instrument station data.
"13.1 Entering Instrument Station Data and Azimuth
3. Press
[OFFSET]
in page three of OBS mode to display
<Offset>.
4. Select “Offset/Dis”.
• The tilt screen is displayed if the instrument is out of level.
Level the instrument.
5. Sight the offset point and press
[MEAS]
in the first page of
the OBS mode screen to begin measurement.
The measurement results are displayed. Press
[STOP]
to
stop the measurement.
20.1 Single-distance Offset Measurement
Occ.Orien.
OffsetDist
OffsetAng.
Offset2D
Offset
Offset Plan
2.000
MEAS
OK
SD
ZA
HA-R