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9 Levelling system operation
9.2 Calibration to zero
Definition
Before working with the different distance sensors is described over the
next few pages, the term calibration to zero must first be explained at
this point.
During each new operation or whenever a distance sensor has been
installed or reinstalled, its current measured value should be calibrated
to zero.
This informs the system of the distance sensor's current installation
height above the reference and simultaneously offers a clear reference
for all subsequent nominal value specifications.
This process is referred to as
calibration to zero
.
Preparation
To do this:
1) Manually move the lower edge of the screed to calibration height; i.e.
to the level which is significant for the subsequent operation (level of the
layer to be paved) and set your traction points to the desired height.
2) Position the distance sensor(s) above the reference.
If working with laser receivers, shift these using the integrated
positioning aid in such a way that the laser beam hits the centre of the
receiver.
Note the specific special features of the various sensors in this case.
These special features are described in the section entitled "Installation
and set-up" for the relevant sensor.
B
A
C
D
E
F
G
B
A
C
D
E
F
G
Calibration height
Calibration height
