Crosshairs - LaserLiner AL 22 Mode D'emploi

Levelling bubble
1. Control: Set horizontal dial onto
0°. Place bubble right into the centre
of the circle on the levelling bubble
by turning the levelling screws. Turn
telescope through 180°/200 gon.
2. Adjustment:
In case the
bubble is now
out of the centre
marking, set
half of the deviation "a"
a
which is (½ a) by
operating the three
calibration screws on
the levelling bubble. To
½a
do so, slightly unscrew
2 calibration screws
each, adjust them and
then finger-tighten these screws
again. After that, adjust levelling
bubble by using the levelling screws,
then check calibration by turning
the whole instrument through
180°/200 gon.
3. Repeat control and calibration
until the bubble of the levelling
bubble remains in the inner circle
after each turn of the instrument.

Crosshairs

1. Control:
Place instrument midway between
two fixed staves A and B which are
some 30 to 40 metres apart.
At the point A on the staff, read the
value a1 and at the point B on the
L=30-40 m
a
1
½L
other staff, secure the value b1.
Calculate the height difference (a1 -
b1).
The result you get is right, even with
the crosshairs dejusted, because the
distances between both staves are
equal.
a
2
2 m
Now place instrument in a distance
of approx. 2 m away from staff A and
read the value a2. Next, turn the
instrument and aim the level at
point B on the staff. Read the value
b2 and calculate the height
difference, which is (a2 - b2).
The adjustment of the level is
correct when you get the reading (a1
- b1) = (a2 - b2). This means that the
Calibration
½L
b
2soll
15
ENGLISH
b
1
b
2