Mode And Length Of Vectors - Furuno FR-7062 Operator's Manual

6.8 Mode and Length of Vectors

True or relative vector
Target vectors are displayed in relative or true
mode. Own ship does not have a vector in rela-
tive mode.
Vector length
From the ARP-10 MENU, Vector Length can
be set to 30 seconds, 1, 3, 6, 15 or 30 minutes
and the selected vector time is indicated on the
screen.
The vector tip shows an estimated position of
the target after the selected vector time elapses.
It can be valuable to extend the vector length to
evaluate the risk of collision with any target.
Past position display
The ARP-10 displays equally time-spaced dots
(maximum 5 dots) marking the past positions
of any targets being tracked.
If a target changes its speed, the spacing will be
uneven. If it changes course, its plotted course
will not be a straight line in TM mode.
Operational warnings
There are two main situations which cause the
ARP-10 to trigger visual and audible alarms:
CPA/TCPA alarm
Lost target alarm
CPA/TCPA alarm
Visual and audible alarms are generated when
the predicted CPA and TCPA of any target be-
come less than their preset limits. The audible
alarm continues for 10 seconds.
The ARP-10 continuously monitors the pre-
dicted range at the Closest Point of Approach
(CPA) and predicted time to CPA (TCPA) of
each tracked target to own ship.
When the predicted CPA of any target becomes
smaller than a preset CPA alarm range and its
predicted TCPA less than a preset TCPA alarm
limit, the ARP-10 releases an audible alarm. In
addition, the target plot symbol changes to a
triangle and flashes together with its vector.
6-6
Provided that this feature is used correctly, it
will help prevent the risk of collision by alert-
ing you to threatening targets. It is important
that GAIN, A/C SEA, A/C RAIN and other ra-
dar controls are properly adjusted and the ARP-
10 is set up so that it can track targets effectively.
CPA/TCPA alarm ranges must be set up prop-
erly taking into consideration the size, tonnage,
speed, turning performance and other charac-
teristics of own ship.
Follow the steps shown below to set the CPA/
TCPA alarm ranges:
1. Open the "ARP-10 MENU".
2. On the "CPA Set" line, select a CPA limit
desired. (Off, 0.5, 1, 2, 3, 5, 6 nm)
3. Press the [ACQ/ENTER] key.
4. On the "TCPA Set" line, select a TCPA limit
desired. (30s, 1, 2, 3, 4, 5, 6, 12M)
5. Press the [ACQ/ENTER] key.
6. Press the [MENU] key to close the menu.
The flashing of the triangle plot symbol and
vector remains on the screen until the danger-
ous situation is no longer present or you inten-
tionally terminate tracking of the target by using
the [SELECT/CANCEL] key.
Lost target alarm
When the system detects a loss of a tracked tar-
get, the target symbol becomes a flashing dia-
mond.