Chapter 6 MDC-1840BB/1841BB/1860BB/1810BB/1820BB Series
Using The Menu
Operation Manual
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6.6.4 Alarm display
When 10 minutes has elapsed since a target has been plotted on the screen, the
system judges that the reliability of the plot data is lost, and accordingly turns the
audio alarm on together with the screen message “UNRELIABLE PLOT DATA” and
the blinking symbol shown. Responding to the audible alarm and the screen
message, you must update the plot. If you leave the plotted data without updating for
15 minutes, all symbols and the data currently plotted on the screen will be
automatically deleted.
6.6.5 Explanation of the EPA terms
TARGET ID:
The target ID number can be tagged on each displayed target from 1 to 10.
AGE:
The time elapsed from when a target is plotted. The unit is in minute(s).
CPA (Closest Point of Approach):
The closest distance of a plotted target to own ship. The unit is in nautical mile(s).
TCPA (Time to CPA):
The time required for a target reaching CPA.
CRS/COG (Course/Course Over Ground):
The course of a target plotted is shown. The course can be switched to true or relative
by pressing the TRUE/REL key.
STW/SOG (Speed):
The true speed of a plotted target, can be switched to true or relative by pressing the
TRUE/REL key.
Figure 6.5 Plotting sequence
Vector
Deleted plot
Plot 1
Plot 2
Plot 3
Plot 4
Plot 5
Current target
