5.2 Check and adjustment of the datum point
[Check]
1Set up the instrument on the tripod halfway between two walls or pillars about 40m away so that the ‘X side’ of the instrument faces the ‘Wall A’ and level it.
2Operate the instrument and turn on the power to the detector. (use the detection accuracy initially set.)
3Mark the reference point detected for both walls. (A,B)
4Arrange a pair of target plates (with the same scale) and fix them to the walls (A and B) so that the center values of the target plates coincide with the reference point marks.
5Loosen the center screw of the tripod to turn the instrument 180 for the ‘X side’ to face the ‘Wall B’ and tighten the center lock screw again for the instrument to be leveled again.
Over view
X side
(Keypad)
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