Trimble Laser GL720

Adjusting the calibration at the laser

Press both axes alignment buttons to clear any stored rake angle

Position the receiver at the midpoint of the two marks on the wall

Add/subtract grade in the appropriate axis using the up/down buttons

Store the new calibration value and zero out the grade display using the hidden button sequence

Rotate the laser 180° back to the original face and ensure axis is less than 5/16 in. (8 mm) from the midpoint line

Is additional adjustment required?

Repeat Step 1 through Step 3 if additional adjustment is required

After adjusting the 2 axis, rotate the laser 90° and repeat the process starting with the +1 axis facing the wall

Set up the laser 90 m (300 ft) from a wall.

Set the grade to 0.000% in both axes.

Raise/lower the receiver until you get an on-grade reading for the +  axis and make a mark on the wall.

Rotate the laser 180° (–  axis toward the wall) and allow the laser to re-level.

Raise/lower the receiver until you get an on-grade reading for the –  axis and make a mark on the wall.

Measure the difference between the two marks (in inches or mm).

External Optical Components Cleaning

Ensure all external optical components are cleaned using a good-quality glass cleaner and a soft cloth

Blow off any loose debris before cleaning surfaces

Laser Surface and Battery Housing Cleaning

Wipe off dust or dirt from the laser's outer surface with a moist, clean cloth

Clean inside the battery housing with a moist, clean cloth

Clean all corroded battery contacts