Alarms - Furuno GP-280 Operator's Manual

12.13 Alarms

12.13.1 CPA/TCPA alarm
Audio and visual alarms are generated when the predicted CPA and TCPA of any target become
less than their preset limits. Press the [CLR] key to acknowledge and silence the CPA/TCPA
audio alarm.
The ARP continuously monitors the predicted 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 releases an audio alarm. In
addition, the target plot symbol changes to a triangle and flashes together with its vector.
Provided that this feature is used correctly, it will help prevent the risk of collision by alerting you
to threatening targets. It is important that GAIN, A/C SEA, A/C RAIN and other radar controls are
properly adjusted and the ARP is set up so that it can track targets effectively.
CPA/TCPA alarm ranges must be set up properly taking into consideration the size, tonnage,
speed, turning performance and other characteristics of own ship.
The CPA/TCPA alarm feature should never be relied upon as a sole means for detecting the risk
of collision. The navigator is not relieved of the responsibility to keep visual lookout for avoiding
collisions, whether or not the radar or other plotting aid is in use.
Follow the steps shown below to set the CPA/TCPA alarm ranges:
1. Press [MENU], [9], [3], [5] to open the ARP menu, and select Page 1.
2. Press [↑] or [↓] to select CPA Set.
3. Press [←] or [→] to choose CPA limit desired (or Off).
4. Press [↓] to choose TCPA Set.
5. Press [←] or [→] to choose TCPA limit desired (or Off).
6. Press the [MENU] key several times to close the menu.
Silencing CPA/TCPA audio alarm
Press the [CLR] key to acknowledge and silence the CPA/TCPA audio alarm.
The flashing of the triangle plot symbol and vector remain on the screen until the dangerous
situation is no longer present or you intentionally terminate tracking of the target by using the
[CANCEL] key.
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