Furuno FAR-28x7 Series - Manual (Page 135)

3. ARP OPERATION
3-9
3.7 ARP Symbols and ARP Symbol Attributes
3.7.1 ARP symbols
The symbols used in this equipment comply with IEC 60872-1.
Item Symbol Status Remarks
Initial stage
Broken square around an echo to indicate
the target under acquisition and initial
stage of tracking, before steady-state
tracking.
Between 20 and 60 scans of the antenna
after acquisition (vector still unreliable)
Steady tracking
Solid circle with vector indicating steady
state tracking (60 scans after acquisition)
(flashing)
CPA alarm Plotting symbol changes to an equilateral
triangle, flashing to indicate the target is
predicted to come into CPA or TCPA.
CPA alarm
acknowledge Flashing stops after CPA/TCPA alarm is
acknowledged.
Automatically
acquired targets
(flashing)
Lost target Lost target is indicated by flashing
diamond symbol. The diamond is formed
from two equal triangles. Flashing stops
after lost target alarm is acknowledged.
Initial stage
Plotting symbol selected for a target
acquired manually is shown in bold broken
lines.
Bold broken square for 20 - 60 scans (3
scans for HSC) of the antenna after
acquisition
Steady tracking Manual plotting symbol in a bold solid
circle (60 scans after acquisition)
(flashing)
CPA alarm
(collision course)
Plotting symbol changes to an equilateral
triangle flashing if a target is predicted to
come into the preset CPA or TCPA.
Flashing stops after CPA/TCPA alarm is
acknowledged.
Manually
acquired targets
(flashing)
Lost target Lost target is indicated by flashing
diamond symbol. The diamond is formed
from two equal triangles. Flashing stops
after lost target alarm is acknowledged.
Guard zone
(flashing)
On target passing
through operator-set
guard zone Plotting symbol changes to an equilateral
triangle, apex down, flashing together with
vector if target enters guard zone.
Target selected
for data readout
01
On selected target Target data (range, bearing, course,
speed, CPA and TCPA)
Reference target
R
In 60 scans,
changes to
○
R
On reference target Used to calculate own ship’s
over-the-ground speed (echo-referenced
speed) for ground stabilization.