Sperry Marine Visionmaster FT ECDIS, User Manual

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Basic Operation of ECDIS ECDIS User Guide
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Safety Checking
The safety checking facility provides the operator with advanced warning
that own ship may be headed towards objects that could endanger the
safety of own ship, as indicated in the ENC
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or mariner object database.
The system periodically searches the chart database and mariner
objects
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database for objects that could endanger the safety of own ship.
Contours, prohibited areas, and areas with special conditions are
considered dangerous if their depth is less than own ship’s safety depth or
no depth is defined for that object.
All objects above the water are considered dangerous if their clearance is
less than own ship safety height. When an object currently not in the list of
dangerous objects intersects own ship's safety region, the object is added
to the Danger List in the Chart Dangers menu. The display of ownship’s
safety region is controlled from the Local Display area of the Chart Dangers
menu.
In addition to the display of a safety region, an ECDIS display also enables
Safety Contour , NAV Hazards and Special Condition areas to be
highlighted for ownship. For information on these features refer to Chart
Dangers.
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Electronic Nautical Chart. Chart data conforming to specification published in IHO Special
Publication No. 57 (S57). Charts complying with this specification are available from various
suppliers.
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Mariner object s are selected from a list of pre-defined object types which have data
assigned to them, such as category, type, description and position. Mariner objects are then
saved and retrieved from a database and can be displayed on the chart, assigned to a layer or
exported to an external system. For details refer to Chapter 4 `Charts’, Manual Update