Sperry Marine Visionmaster FT ECDIS, User Manual

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Charts ECDIS User Guide
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underwater obstructions) that are shallower than the Shallow Contour
specified in Chart Depths/Heights.
If no added breath is defined (i.e. the value is set at 0 ) then safety checking
is to the beam of the ship. Unlike Look Ahead range no caution is
generated when added breadth is at
0 .
2. To change the value click in the Added Breadth field and move
the trackball left or right. As the safety breadth is changed the width
of the safety region either side of the ship’s beam changes
accordingly.
Alert Priority
The Alert Priority area includes the following settings:

Navigational Hazards

Special Condition Areas
When either of these check boxes are ticked any current Navigational
Hazards or Special Condition Area s safety region Cautions in the Danger
List, will change to Warning status. These alerts will then show in the Alert
Status Indicator (provided that here are no pre-existing unacknowledged
Alarms.
Local Display
Own ship safety region is switched on/off by ticking the Show Safety
Region check box. The ownship safety region boundary box is displayed in
white. The length and width of the safety region is governed by the current
Look Ahead values. If these are changed, the length and width of the
safety region adjusts accordingly. As own ship moves across the screen,
the line is redrawn every 30 seconds.
When there is a difference between the COG and the Heading the safety
region will display a dog legged rectangle, this being the calculated safety
region taking into account the different COG and HDG values. If the COG
and HDG bearings are the same the safety region rectangle is drawn as
straight lines.