Leveling Accuracy - Bosch GRL300HV Operating And Safety Instructions Manual

Automatic leveling
Overview
After switching on, the laser tool automatically
detects the horizontal or vertical position. To
change between the horizontal and vertical
position, switch the laser tool off, reposition it
and switch on again.
After switching on, the laser tool checks the
horizontal and vertical position and
automatically levels out any unevenness
within the self-leveling range of
approx. 8 % (5°).
When the laser tool is inclined by more than
8 % after switching on or after a position
change, leveling in is no longer possible. In
this case, the rotor is stopped, the laser
flashes and leveling indicator 3 continuously
lights up red. Reposition the laser tool and
wait for it to re-level. Without repositioning, the
laser is automatically switched off after 2
minutes and the laser tool after 2 hours.
When the laser tool is leveled in, it
continuously checks the horizontal and
vertical position. Automatic re-leveling takes
place after position changes. To avoid faulty
measurements, the rotor stops during the
leveling process, the laser flashes and the
leveling indicator 3 flashes green.
Shock-warning Function
The laser tool has a shock-warning function;
after position changes or shock to the laser
tool, or in case of ground vibrations, it
keeps the laser tool from leveling in at changed
heights, and thus prevents vertical errors.
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 seconds.
When the leveling-accuracy range is exceeded after
a position change of the laser tool or when heavy
ground vibrations are detected, the shock-warning
function is actuated: The rotation is stopped, the
laser flashes, the leveling indicator 3 goes out and
the shock-warning indicator 1 flashes red. The
current operating mode is stored.
After the shock-warning function has actuated,
press the shock-warning button 2.

Leveling Accuracy

The shock-warning function is restarted and the
laser tool starts the leveling. As soon as the laser
tool is leveled in (leveling indicator 3 continuously
lights up green), it starts in the stored operating
mode. Now, check the height of the laser beam with
a reference point and correct the height, if required.
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 laser 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 indicator 1
flashing red) press it twice. When the shock-
warning function is shut off, the shock warning
indicator 1 goes out.
Influences on Accuracy
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 measuring distance and can easily reach
two to four times the deviation at 328 ft.
Because the largest difference in temperature
layers is close to the ground, the laser tool
should always be mounted on a tripod when
measuring distances exceeding 65 ft. If
possible, also set up the laser tool in the
center of the work area.
Accuracy Check
Apart from exterior influences, device-specific
influences (such as heavy impact or falling
down) can lead to deviations. Therefore,
check the accuracy of the laser tool each time
before starting your work.
For the accuracy check, an unobstructed
measuring distance of 65 ft on firm ground
between two walls A and B is required. With
the laser 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 laser tool in the horizontal
-12-
position onto a tripod 21 (accessory) or
place it on a firm and level surface near
wall A. Switch the laser tool on.