As far as I know, the Rotation Laser will physically auto level, when you balance the Unit within the limitation. For Total Station have duel axis sensors to measure how much the Unit off from Level positions and adjust them in Hz and Vz Angle values (digital).
It's mandatory to do Calibrate the Compensators frequently, at least 1 a month or any time you what best accuracy from your TS.
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Road and Rail Excavations
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