Reference Target (Reference) - JRC JMA-5312-6 Instruction Manual

5.2.6 Reference Target (Reference)

The system can display the own ship's speed. To do so, it sets a reference target by tracking a target for
which ground fixed.
Attention
The reference target function is to be used if the own
ship's speed cannot be displayed normally due to trouble
such as a speed sensor malfunction. Do not use the
reference target function except in emergencies.
If the speed or course of the own ship is changed or a new
reference target is set, the displayed speed may take 3
minutes or more to reach the specified speed after the
speed / course change or the setting.
Even after 3 minutes or more has passed, the speed may
differ from the specified speed depending on the tracking
condition.
If a large radar echo such as a land target is set as a
reference target, the vectors of the speed and other
tracking targets will not be displayed correctly and may
cause an accident.
If a sailing ship is set as a reference target, the vectors of
the speed and other tracking targets will not be displayed
correctly and may cause an accident.
If the REF. is selected for the speed sensor, the AIS
function cannot be turned on.
If the reference target is lost or the target tracking
function is stopped, the speed sensor is placed in manual
mode MAN .
The loss of a reference target may have a major impact on
the accuracy of the results for true speed and true course
of the target and that own speed will be degraded.
The reference targets are only used for the calculation of
true speed.
5.2 Target Tracking Operation
5-24
5