Bosch GLL 2-50 Professional Originalbetriebsanleitung Seite 20

OBJ_BUCH-817-004.book Page 20 Thursday, March 19, 2009 12:32 PM
20 | English
Working without Automatic Levelling
(see figure D)
For work without automatic levelling, push the
On/Off switch 7 to the "
the automatic levelling is switched off, the laser
lines flash continuously.
When the automatic levelling is switched off, the
measuring tool can be held by hand or placed on
an inclined surface. In cross-line operation, the
two laser lines do not necessarily run at a right
angle to each other.
Levelling Accuracy
Influences on Accuracy
The ambient temperature has the greatest in-
fluence. Especially temperature differences
occurring from the ground upward can divert
the laser beam.
Because the largest difference in temperature
layers is close to the ground, the measuring tool
should always be mounted on a tripod when
measuring distances exceeding 20 m. If possi-
ble, also set up the measuring tool in the centre
of the work area.
Apart from exterior influences, device-specific
influences (such as heavy impact or falling
down) can lead to deviations. Therefore, check
the accuracy of the measuring tool each time
before starting your work.
First, check both the height as well as the level-
ling accuracy of the horizontal laser line, then
the levelling accuracy of the vertical laser line.
Should the measuring tool exceed the maximum
deviation during one of the tests, please have it
repaired by a Bosch after-sales service.
1 609 929 S02 | (19.3.09)
Checking the Height Accuracy
of the Horizontal Line
For this check, a free measuring distance of
on" position. When 5 metres on a firm surface between two walls A
and B is required.
– Mount the measuring tool onto a tripod or
– Direct the laser against the close wall A and
– Turn the measuring tool by 180°, allow it to
place it on a firm and level survace close to
wall A. Switch on the measuring tool. Select
cross-line operation with automatic levelling.
A
5 m
allow the measuring tool to level in. Mark the
centre of the point where the laser lines
cross each other on the wall (point I).
A
180˚
level in and mark the cross point of the laser
lines on the opposite wall B (point II).
B
B
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