Accuracy Check Of The Measuring Tool - CST/BERGER LMPL20 Manual Original

Setting the First Canal Pipe
– Set the first pipe of the canal to be laid against the
flange of the manhole cone or riser.
– Check if the laser beam is still in the centre of the
target plate by positioning the target plate at the
beginning of the canal pipe.
– Afterwards, position the target plate at the end of
the canal pipe (the spirit level of the target-plate
stand must be level).
– Underlay the canal pipe until the laser beam is in
the centre of the target plate.
Setting Up the Measuring Tool in a Canal Pipe
(see figure F)
When the first canal pipe has already been set, the
measuring tool can easily be placed in the pipe.
– Fasten the legs with the appropriate length for the
canal pipe to the measuring tool.
– Position the measuring tool in the canal pipe, tak-
ing care that it is stands properly and aligned at the
bottom of the canal pipe.
– Place the target plate at the end of the pipe to be
installed and ensure that it is properly positioned
(target-plate stand must be properly aligned with
its spirit level).
– The laser beam can now be aligned to the centre
of the target plate using the remote control or the
control panel buttons of the measuring tool
or
you can align the laser beam from the target plate
with the remote control.
When using the control panel buttons on the measur-
ing tool, it may be necessary to have a second person
positioned at the target plate when the distance
between the manhole cones or risers is very large.
Checking Canal Grades (see figure G)
To ensure that the canal is being laid with the right
grade, it can be necessary to check if the laser beam
was adjusted correctly. This should be checked after
approx. 8 – 15 m of canal have been laid.
– Use a levelling instrument, rotational laser level or
theodolite and measure reference height A at the
starting point of the canal.
– Measure height B at the end point of the canal with
the same instrument.
– Determine the height difference between A and B.
– Measure distance D between the starting and end
point.
Calculate the grade with the following formula:
Height difference (A – B)/clearance D * 100 =
grade of the laid canal pipe.
If the measured grade should not be consistent with
the desired grade, check the settings of the measur-
ing tool and the position of the target plate.
2 610 A13 727 • 13.10.10

Accuracy Check of the Measuring Tool

The calibration of the measuring tool should be
checked periodically. Allow time (at least 60 seconds)
for the measuring tool to self-level before checking the
calibration.
Checking the Grade Accuracy
(see figures H1 – H3)
– Position the measuring tool on a level surface.
– Switch the measuring tool on and allow it to level.
– Set the grade exactly to 00.000 %.
– Mark two points A und B in line with the laser
beam.
Point A should be approx. 0,3 m away from the
measuring tool, point B approx. 30 m away.
– Position one levelling rod directly on point A and
mark the location where the laser beam impinges
on the levelling rod as A1.
– Position the same levelling rod directly on point B
and mark the location where the laser beam
impinges on the levelling rod again as B1.
– Now position the measuring tool on the other side
(approx. 0,3 m behind point B).
– Check that the laser beam impinges upon mark B1
when positioning the levelling rod at point B. If
necessary, adjust the height of the measuring tool
so that the laser beam impinges upon B1.
– Now place the levelling rod on point A. When the
laser beam impings on point A1, the measuring
tool is calibrated correctly.
If the laser beam impinges above or below point
A1, have the measuring tool checked by an author-
ised Bosch after-sales service.
Checking the Accuracy of the Lateral Alignment
(see figures I1 – I3)
– Position the measuring tool approx. 15 m in front
of a levelling rod.
– Switch the measuring tool on and allow it to level.
– Centre the laser beam (no deviation left or right)
and then turn the measuring tool so that the laser
beam impinges on the centre of the levelling rod.
Mark point C.
– Now deflect the beam toward the right to the max-
imum by pressing button 19.2.
– Now turn the measuring tool so that the laser
beam impinges upon the levelling rod again.
– Allow the measuring tool to level in again.
– When the laser beam impinges on point C, the
measuring tool is calibrated correctly.
If the laser beam impinges above or below point C
(near point C'), have the measuring tool checked
by an authorised Bosch after-sales service.
– Repeat the steps analogue for maximal deflection
toward the left (with button 19.1).
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