Source Of Position - Furuno FMD-3100 Operator's Manual

18.3

Source of Position

The figure below shows how source for position is chosen. The position sensors have
either primary or secondary as input for their calculation. DGPS position sensors are
considered more accurate than other position sensors.
The latitude and longitude position is shown at the top-right position on the chart dis-
play, and in the example below the position source is DGPS. Other indications that
may be displayed in the position area are as follows:
• DR: Shown in yellow when position source is dead reckoning.
• DGPS, GPS: Name of position source.
Position sensor
selected as
high priority
No valid data exists
If the system changes the source of position because of lost sensor data, the system
immediately generates the Alert 472 "Position Source Change".
Valid data exists
Position sensor
Valid data exists
selected as
low priority
No valid data exists
Selected
18. NAVIGATION SENSORS
Backup
dead
reckoning
Position
used by
this system
18-5