Bosch GRL Professional 250 HV Originalbetriebsanleitung Seite 30

OBJ_BUCH-757-006.book Page 30 Wednesday, September 29, 2010 11:21 AM
30 | English
When the measuring tool is inclined by more
than 8 % after switching on or after a position
change, levelling in is no longer possible. In this
case, the rotor is stopped, the laser flashes and
levelling indicator 3 continuously lights up red.
Reposition the measuring tool and wait for it to
re-level. Without repositioning, the laser is auto-
matically switched off after 2 minutes and the
measuring tool after 2 hours.
When the measuring tool is levelled in, it contin-
uously checks the horizontal and vertical posi-
tion. Automatic re-levelling takes place after po-
sition changes. To avoid faulty measurements,
the rotor stops during the levelling process, the
laser flashes and the levelling indicator 3 flashes
green.
Shock-warning Function
The measuring tool has a shock-warning func-
tion; after position changes or shock to the
measuring tool, or in case of ground vibrations,
it keeps the measuring tool from levelling in at
changed heights, and thus prevents vertical er-
rors.
To switch on the shock-warning function, press
the shock-warning button 2. The shock-warning
indicator 1 continuously lights up green, and the
shock-warning function is activated after 30 sec-
onds.
When the levelling-accuracy range is exceeded
after a position change of the measuring tool or
when heavy ground vibrations are detected, the
shock-warning function is actuated: The rota-
tion is stopped, the laser flashes, the levelling
indicator 3 goes out and the shock-warning indi-
cator 1 flashes red. The current operating mode
is stored.
After the shock-warning function has actuated,
press the shock-warning button 2. The shock-
warning function is restarted and the measuring
tool starts the levelling. As soon as the measur-
ing tool is levelled in (levelling indicator 3 con-
tinuously lights up green), it starts in the stored
operating mode. Now, check the height of the la-
ser beam with a reference point and correct the
height, if required.
2 610 A14 633 | (29.9.10)
When the function is not restarted by pressing
button 2 after the shock-warning function has
actuated, 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-warning button 2 once, or, when the
shock warning is actuated (shock-warning indi-
cator 1 flashing red) press it twice. When the
shock-warning function is shut off, the shock-
warning indicator 1 goes out.
Levelling Accuracy of the Rotational
Laser Level
Influences on Accuracy
The ambient temperature has the greatest influ-
ence. Especially temperature differences occur-
ring from the ground upward can divert the laser
beam.
The deviations play a role in excess of approx.
20 m measuring distance and can easily reach
two to four times the deviation 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 possi-
ble, 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 be-
fore starting your work.
For the accuracy check, an unobstructed meas-
uring distance of 20 m on firm ground between
two walls A and B is required. With the measur-
ing tool in the horizontal position, a transit
measurement is to be carried out across both
axes X and Y (both positive and negative) (alto-
gether 4 complete measurements).
– Mount the measuring tool in the horizontal
position onto a tripod 26 (accessory) or
place it on a firm and level surface near
wall A. Switch the measuring tool on.
Bosch Power Tools