David White 3900HV, Руководство пользователя

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-12-
ACCURACy CHECK
The ambient temperature has
the greatest influence. Especially
temperature differences occurring
from the ground upward can divert
the laser beam. The deviations play a
role in excess of approx. 65-ft (20m)
measuring distance and can easily
reach two to four times the deviation
at 330-ft (100m). Because the largest
difference in temperature layers is
close to the ground, the instrument
should always be mounted on a
tripod when measuring distances
exceeding 65-ft (20m). If possible,
also set up the instrument in the
center of the work area.
Checking the Leveling Accuracy
Apart from exterior influences,
device-specific influences (such as
heavy impact or falling down) can
lead to deviations. Therefore, check
the accuracy of the instrument each
time before starting your work. A
free measuring distance of 165-ft
(50m) on a firm surface is required for
the check. A reversal measurement
must be carried out over both axes X
and Y (each positive and negative; 4
complete measurements).
– Mount the instrument in the
horizontal position onto a tripod
or place it on a firm and level
surface 100-ft (30m) from a wall.
Switch the instrument on. Position
the X-axis to aim to wall or target
plate.
100 ft (30 m)
H1
Y1
100 ft (30 m)
H1
H2
Y2
100 ft (30 m)
1.5-ft
(0.5 m)
A
H1
B
100 ft (30 m)
1.5-ft
(0.5 m)
A
H1
H2
B
100 ft (30 m)
1.5-ft
(0.5 m)
A
H1
D
H3
H2
B
100 ft (30 m)
1.5-ft
(0.5 m)
A
H1
H2
B
D
180°
100 ft (30 m)
H1
X1
100 ft (30 m)
H1
H2
X2
D
180°
180°
180°
3900HV
– After the leveling, mark the center of
the laser beam on wall (point
H1
).
– Rotate the instrument by 180°,
allow it to level in and mark the
center point of the laser beam on
the wall (point H2 ).
100 ft (30 m)
H1
Y1
100 ft (30 m)
H1
H2
Y2
100 ft (30 m)
1.5-ft
(0.5 m)
A
H1
B
100 ft (30 m)
1.5-ft
(0.5 m)
A
H1
H2
B
100 ft (30 m)
1.5-ft
(0.5 m)
A
H1
D
H3
H2
B
100 ft (30 m)
1.5-ft
(0.5 m)
A
H1
H2
B
D
180°
100 ft (30 m)
H1
X1
100 ft (30 m)
H1
H2
X2
D
180°
180°
180°
3900HV
– The difference
D
of both marked
points H1 and H2 on wall is the
actual deviation of the instrument
for the measured axis.