Kongsberg EM 712, Maintenance Manual

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451106/B
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 systems 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 often located close to the vessel’s centre of gravity. Both
of these are physically positioned far away from the transducer on a depth sensor,
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.
Reference points must be established on the vessel at selected positions. These are
needed during measurements of the sensor positions. Visual markings at these positions
should be prepared and noted on the vessel drawings with
X , Y and Z coordinates in the
vessel coordinate system.
Kongsberg EM 712 Maintenance Manual