Using Radar To Track Targets And Avoid Collisions - Raymarine a65 Installation And Operation Instructions Manual

13.13 Using radar to track targets and
avoid collisions
The Guard Zone , VRM/EBL and MARPA functions will help you
track targets and avoid collisions.
With a radar connected to your multifunction display, you can:
• Assess how far away a target is and its bearing (VRM/EBL).
• Set an alarm to trigger when a target is within a specified zone
(Guard Zone).
• Display detailed information on tracked targets (MARPA).
• Display the range and bearing of a target.
Setting up a radar guard zone
From the radar application:
1. Select Menu.
2. Select Track Targets.
3. Select Guard Zone Set-up.
4. Select Zone so that On is highlighted.
Selecting Zone will switch the zone On and Off.
5. Select Adjust Zone.
6. Select Shape: to switch between Sector or Circle.
7. Select Outer: .
The Outer numeric adjust control is displayed.
8. Adjust the outer edge of the guard zone to the required distance.
9. Select Ok to close the numeric adjust control.
10. Select Inner: .
The Inner numeric adjust control is displayed.
11. Adjust the inner edge of the guard zone to the required distance.
12. Select Ok to close the numeric adjust control.
13. Select Width: .
The Width numeric adjust control is displayed.
14. Adjust the width of the guard zone in degrees.
15. Select Ok to close the numeric adjust control.
16. Select Bearing: .
The Bearing numeric adjust control is displayed.
17. Adjust the bearing of the guard zone in degrees port or degrees
starboard.
18. Select Ok to close the numeric adjust control.
Note: Guard zone width and bearing can only be adjusted when
the Shape: is set to Sector.
Guard zone context menu
The guard zone function includes a context menu which provides
additional menu items.
The context menu provides the following menu items:
• Acquire Target.
• Adjust Zone
• Zone Off
Accessing the context menu
You can access the context menu by following the steps below.
1. New e Series or New c Series:
i. Selecting a location, object or target on-screen and pressing
the Ok button.
2. Touchscreen multifunction displays:
i. Selecting an object or target on-screen.
ii. Selecting and holding on a location on-screen.
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Adjusting guard zone sensitivity
You can adjust the threshold at which the alarm is triggered by a
target entering the guard zone.
1. Select Menu.
2. Select Track Targets.
3. Select Guard Zone Set-up.
4. Select Sensitivity.
The sensitivity numeric adjust control is displayed.
5. Adjust the sensitivity to the required value.
6. Select Ok to confirm setting and close the numeric adjust control.
The guard zone sensitivity setting can also be accessed from the
Alarms menu: homescreen > Set-up > Alarms > Guard Zone
> Sensitivity.
MARPA overview
MARPA is used for target tracking and risk analysis in the radar
application.
With an accurate heading sensor connected to your multifunction
display, you can use the Mini Automatic Radar Plotting Aid (MARPA)
functions for target tracking and risk analysis. MARPA improves
collision avoidance by calculating information for tracked targets,
and provides continuous, accurate, and rapid situation evaluation.
The number of targets that you can track at any one time is
dependent on the model of radar scanner that you are using.
MARPA tracks acquired targets, and calculates the target's speed
and course.
Each target tracked can be displayed with a graphic indicating the
Closest Point of Approach (CPA), and Time to Closest Point of
Approach (TCPA). The calculated target data can also be shown on
your screen. Each target is continually assessed and an audible
alarm is sounded if a target becomes dangerous, or is lost.
For effective MARPA operation, your multifunction display must
have accurate heading and speed data for your vessel. The better
the quality of the heading and speed data, the better MARPA will
perform. For the best heading data, a Raymarine SMART heading
sensor or a gyro-stabilized autopilot is required.
In True Motion mode, Speed Over Ground (SOG) and Course Over
Ground (COG) information is required to show true target course
and speed.
In Relative Motion mode, heading and speed information is required.
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Safety notices
MARPA can improve collision avoidance when used wisely. It is
your responsibility to exercise common prudence and navigational
judgement.
There are conditions where acquiring a target may become difficult.
These same conditions may be a factor in successfully tracking a
target. Some of the conditions are:
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Description
Safe target
Lost target
Dangerous target
Target being acquired
New a Series / New c Series / New e Series
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