Si-tex SNS-1100, User Manual

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- User Manual
3.7.1 AIS System Definitions
• Target
It is a vessel equipped with AIS. Information about the Targets is being received by AIS Receiver
and displayed on the screen.
• CPA
Closest Point of Approach is the closest distance that will be achieved between your vessel
and the tracked Target, based on your vessel’s speed and direction and the Target’s speed and
direction.
• CPA Limit
This is the distance from your vessel that a Target may reach before a Target is deemed a
threat.
• CPA Alarm
Occurs if CPA is less or equal to CPA Limit. This test is done for active Targets only.
• TCPA
Time to closest Point of Approach is the time remaining until the CPA will occur.
• TCPA Limit
This is the time remaining before the CPA is reached.
• TCPA Alarm
Occurs if TCPA is less or equal to TCPA Limit. This test is done for active Targets only and if CPA
value is less or equal to CPA Limit.
• Radio Call Sign
International call sign assigned to vessel, often used on voice radio.
• Name
Name of ship, 20 characters.
• MMSI
Maritime Mobile Service Identity.
• MMSI number
A unique 9 digit number that is assigned to a DSC radio station. It primarily registers the
boat information in the U.S. Coast Guard’s national distress database for use in emergency
situations.
• Active Target
Target located within the Activation Range. Active Target is represented by oriented triangle with
COG and Heading vectors. Rate of turn may also be displayed.
• Dangerous Target
Target detected by CPA or TCPA Alarm. Dangerous Target is Active Target by definition. For
better visibility Dangerous Target symbol is flashing.
• Sleeping Target
Target located outside the Activation Range. Sleeping Target is represented by a small oriented
triangle.
• Lost Target
When the AIS info is not received from that vessel for 3.5 minutes. The presentation will be a
flashing black triangle with a cross through.
• Activation Range
Range around your boat where Targets become active. AIS Target become active within this
range. Activation Range should be greater than CPA Limit by definition.
• SART
Search and Rescue Target, a target with active Search-and-Rescue status, i.e. a declared
emergency (vessel, man over board send my portable SART equipment, etc.)
NOTE
A Target is removed from the screen if data is not received for 10 minutes.
The maximum number of tracked Targets is 200.