Metabo MLL 3-20, Operating Instructions Manual

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11
Additional functions
Function: Height adjustment
Fig. (B6)
Use the clamping lever (14) to adjust the height of the laser housing.
Function: Fine adjustment
Fig. (B9)
Use the fi ne adjustment (11) to rotate the laser casing to an exceptionally
high degree of precision, which allows the vertical laser lines to be precisely
aligned.
Checking the calibration
The MLL 3-20 crossed line and plumb line laser is designed for use on the
construction sites and left our factory perfectly adjusted. As with any precision
instrument, however, its calibration must be regularly checked.
The unit should be checked before starting any new tasks, particularly when
the unit has been exposed to strong vibrations.
Vertical check
Checking the 2 vertical laser lines
Fig. (C1)
1. Create a reference line e.g. with a plumb line.
2. Set up and align the MLL 3-20 at distance Y in front of this reference line.
3. Compare the laser line with the reference line.
4. Do not allow the laser line to deviate from the reference line by more
than 1 mm over a distance of 2 m!
5. Perform this check for both vertical laser lines.
Checking the plumb-line function
Fig. (C2)
1. Align the MLL 3-20 precisely with one floor marking using
the plumb dot.
2. The projected laser line cross appears on the ceiling.
3. Turn the MLL 3-20 around 180° and align it once again with the floor
marking using the plumb-line dot.
4. The projected laser line cross appears on the ceiling.
The diff erence measured between the markings is twice the actual
discrepancy. With a ceiling height of 5 m, the diff erence should
be no more than 3 mm.
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