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9 Levelling system operation
9.5 Working with the dual sonic sensor
9.5.1 Installation and set-up
The ultrasonic pulses emitted by the dual sonic sensor have more club-
shaped characteristics; i.e. the sound beam becomes wider the further
it moves away from the sensor.
When working with the dual sonic sensor, clearance of > 20 cm around
the sound beam axes must therefore be maintained to reliably avoid
interfering reflections throughout the entire specified working area.
Working area
The optimal working area for the dual sonic sensor lies between 30 cm
and 40 cm.
The dual sonic sensor should be set to a distance of approx. 35 cm
from the reference.
Approx. 35 cm