Nivel System NL520R DIGITAL Manual page 9

Checking the vertical plane
This procedure should be done after calibration of the horizontal plane.
1. Set the laser centered between the walls distanced from each other of 30 m
2. Turn on the laser level.
3. Place the paper sheets on the walls and mark the position of the laser beam.
4. Turn off the instrument. Set the instrument in vertical position near to one of the walls.
5. Turn on the instrument.
6. Mark the position of the laser beam on the paper sheet. Measure the distance
between the markers
7. Do not change the position of the laser and spin it 180°.
8. Mark the position of the laser beam on the paper sheet. Measure the distance
between the markers
9. If the distance between the markers is less than 3mm calibration is not necesery.
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