Sperry Marine Visionmaster FT ECDIS, Руководство пользователя

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Targets ECDIS User Guide
10-54 65900012
Note that setting these values too high may result in targets which are
separate being considered the same target; whilst setting the values too
low may mean that targets that are the same are not correlated, leading to
multiple targets being displayed in the same position.
Lost Target Alerts
This area enables Lost Target alerts to be raised on all nodes and a lost
target alert range limit set, so that any lost targets within a specified
maximum limit from own ship will raise a Lost Target alert.
In ECDIS Watchmode, Raise Alerts is only enabled if Raise Alerts in the
upper Collision Avoidance area is enabled (ticked). If the upper Raise
Alerts checkbox is then disabled (unticked), the lower Raise Alerts setting
remains ticked but becomes ghosted. This ghosted setting will become
restored if the upper Raise Alerts checkbox is reactivated (ticked).
For a description of Lost Targets and the symbology used, see Target
Monitoring.
The default maximum range limit distance is 10 NM. The
minimum/maximum values are 0.1 NM to 100 NM.
Collision Avoidance Criteria
Collision avoidance must be carried out in strict compliance with the
COLREG
47
.
Relative velocity is fundamental to the activity of collision avoidance. The
System calculates relative velocity in both ground and sea stabilisation
modes and presents individual target CPA/TCPA data. This same data is
used when evaluating whether a target is infringing the operator selected
CPA/TCPA, bow crossing and target association limits. The system is
designed in such a way as to minimise errors in the collision avoidance
calculations which result from the sensors selected for stabilisation. In
practice, however, different sensors may contribute to the possibility of
errors in calculation and caution should be used when interpreting the data,
particularly when ground stabilisation is selected.
47
Convention of the International Regulations for the Preventing of Collisions at Sea