©2011 Johnson Level & Tool
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Calibrating
Check and Calibrate the Optical Plummet
To align the optical axis of the optical plummet and the vertical axis,
calibration for the optical plummet is necessary, otherwise the
vertical axis will not be on the true anchor point.
Checking
• Attach the theodolite to a tripod (no leveling required).
• Place a target under the instrument.
• Focus the image of the target then adjust the leveling screws so
that the target is centered in the reticle.
Operating Procedures
Operation
Display
1. Level the instrument accurately with the long vial.
2. Power on the instrument, the vertical angle and horizontal angle
are displayed after the telescope passes zero position.
3. Press the FUNC key once, and then press the V/% key.
4. Rotate the instrument and precisely aim at the clear and stable
target A as high as the instrument in the distance.
5. Press the 0-Set key once.
6. Turn the instrument and aim the right of the vertical plate at the
same target A.
7. Press the 0-Set key and the measured values are set. The
instrument goes back to the angle measurement mode, and the
calibration is finished.
Rotate the
telescope
Aim at the
plate left
position of A
Aim at the
plate right
position of A
• Send the instrument to an authorized repair facility for repairs after operations are repeated many times
without any effect.
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