Aligning The Instrument Before Measuring - Nedo ET-5 Mode D'emploi

4 Preparation for Measurement
4.2

Aligning the instrument before measuring

1 Attach the theodolite to a tripod.
Pre-level the instrument with the help of the
adjustment screws and the circular bubble
installed in the tribrach.
2
Use the optical plummet* or plummet beam*
to align the instrument to the measuring point.
Repeat steps 2 and 3 until the bubble stays
3 centred in any position.
Rotate the theodolite according to the illus-
tration for fine levelling (the horizontal spirit
level should lie exactly between the adjust-
4 ment screws A and B. Align the instrument
using these two screws; the air bubble of the
horizontal spirit level has to be positioned
exactly in the middle of the two marks).
The theodolite is then rotated by 90°.
TIP:
Switch on the theodolite with the
and set the angle indicator of the horizontal
circle to 0 with the
0° 00' 00"). Now turn the theodolite by exactly
5
90° and fix it securely.
The C setting screw EXCLUSIVELY must now
be used for levelling the theodolite. Repeat
steps 4 and 5 until the spirit level stays centred
in any position. It is recommended to check the
level by taking a rotation measurement (180°
rotation).
* Depending on the features: 460812-613 with optical plummet / 460814-613 with laser plummet.
Theodolite ET-5 Operating Instructions
ON/OFF
button (display
OSet
button
EN
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