Bosch GRL Professional 250 HV Original Instructions Manual page 13

OBJ_BUCH-1492-001.book Page 13 Friday, July 1, 2011 12:25 PM
After the shock warning has actuated, press the shock-warn-
ing button 2 on the measuring tool or the shock-warning reset
button 21 on the remote control. The shock-warning function
is restarted and the measuring tool starts the levelling. As
soon as the measuring tool is levelled in (levelling indicator 3
continuously lights up green), it starts in the stored operating
mode. Now, check the height of the laser beam with a refer-
ence point and correct the height, if required.
When, after the shock-warning function has actuated, the
function is not restarted by pressing button 2 on the measur-
ing tool or the shock-warning reset button 21 on the remote
control, the laser is automatically switched off after 2 minutes
and the measuring tool after 2 hours.
To switch off the shock-warning function, press shock-warn-
ing button 2 once, or, when the shock warning is actuated
(shock-warning indicator 1 flashing red) press it twice. When
the shock-warning function is shut off, the shock-warning in-
dicator 1 goes out.
The shock-warning function cannot be switched on or off with
the remote control; it can only be restarted after having actu-
ated.
Levelling Accuracy of the Rotational Laser Level
Influences on Accuracy
The ambient temperature has the greatest influence. Espe-
cially temperature differences occurring from the ground up-
ward can divert the laser beam.
The deviations play a role in excess of approx. 20 m measur-
ing distance and can easily reach two to four times the devia-
tion at 100 m.
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 possible,
also set up the measuring tool in the centre of the work area.
Accuracy Check of the Measuring Tool
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.
For the accuracy check, an unobstructed measuring distance of
20 m on firm ground between two walls A and B is required.
With the measuring tool in the horizontal position, a transit
measurement is to be carried out across both axes X and Y (both
positive and negative) (altogether 4 complete measurements).
– Mount the measuring tool in the horizontal position onto a
tripod 31 (accessory) or place it on a firm and level surface
near wall A. Switch the measuring tool on.
A
20 m
Bosch Power Tools
– After levelling, direct the laser beam in point operation on-
to the close wall A. Mark the centre point of the laser beam
on the wall (point I).
A
180°
– Turn the measuring tool around by 180°, allow it to level in
and mark the centre point of the laser beam on the oppo-
site wall B (point II).
– Without turning the measuring tool, position it close to wall
B. Switch the measuring tool on and allow it to level in.
A
– Align the height of the measuring tool (using the tripod or
by underlaying, if required) in such a manner that the cen-
tre point of the laser beam is projected exactly against the
previously marked point II on wall B.
A
– Rotate the measuring tool by 180° without changing the
height. Allow it to level in and mark the centre point of the
laser beam on wall A (point III). Take care that point III is
as vertical as possible above or below point I.
– The difference d of both marked points I and III on wall A
B
amounts to the actual deviation of the measuring tool for
the measured axis.
Repeat the measuring procedure for the other three axes. For
this, turn the measuring tool prior to each measuring proce-
dure by 90°.
On the measuring section of 2 x 20 m = 40 m, the maximum
allowable deviation is:
40 m x ±0.1 mm/m = ±4 mm.
English | 13
B
B
B
180°
1 619 929 J23 | (1.7.11)