Kongsberg EM 2040 MKII, Руководство по установке

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Calibration
During the sea trials, calibration surveys are required as described in the EM 2040 MKII
end user documentation.
In order to check and verify the performance of the EM 2040 MKII system, we strongly
recommend that calibration surveys are done at regular intervals, or prior to any large
survey.
The calibration process is described in detail in the Seafloor Information System (SIS)
Operator Manual.
Note
Calibration must be taken seriously. The final verification of correct installation can
only be done during calibration at sea. Installation and operational parameters that
do not meet the accuracy requirements may lead to incorrect data. To achieve the best
results, the calibration must be planned and done carefully.
Vessel coordinate system
The vessel coordinate system is established to define the relative physical locations of
system units and sensors.
When you have several different sensors and transducers on your vessel, and you wish
each of them to provide accurate data, you need to know their relative physical positions.
The antenna of a position sensor is typically mounted high above the superstructure,
while a motion sensor is located close to the vessel’s centre of gravity. Both of these
are physically positioned far away from the transducer, which may be located closer to
the bow.
Very often, the information from one sensor depends on data from an other. It is then
important that the relevant measurements are compensated for these relative distances.
Example
If you wish to measure the actual water depth, you will need to know the
vertical distance from the echo sounder transducer to the water line. Since
the vessel’s displacement changes with the amount of cargo, fuel etc, the
physical location of the water line on the hull must either be measured at a
regular basis, or measured with a second sensor.
Dimensional surveying and alignment