NORTHROP GRUMMAN NAVITWIN IV, Руководство по эксплуатации, установке и обслуживанию

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056360/E NAVITWIN IV
2-2 External control devices
2.2 External control devices
Depending on the installation, external devices may be installed to
remotely control certain functions of the NAVITWIN IV:
• An external selector switch may be used to reverse the heading
(apply a 180° offset), e.g. for operation in double-ended ferries.
This function may also be triggered automatically upon switchover
between the fore and aft steering stands.
• The audible alarm at the NAVITWIN IV may be muted externally, e.g.
from an alarm panel or a central alarm management system.
• External push buttons may be used to adjust the display brightness.
• An external dim controller may send serial dimming commands to
adjust the display brightness (central dimming).
2.3 Power-up Sequence
The NAVITWIN IV is not equipped with a power switch. The device pow-
ers up as soon as supply power is applied to the gyrocompass system:
Upon power up, the startup screen
is shown and the initial system test
is executed.
A status line at the bottom of the
screen indicates the progress and
results of the test.
When the system test has been
passed, the NAVITWIN IV enters the
normal operational mode.
The heading source window dis-
plays the heading data received
from the available compasses.
The display data window shows
additional data, such as speed,
position, time etc., if available.
Off Hdg.
10°
Set Hdg.
246.0
DISPLAY DATA
MONITOR
ALARM
NO ACTIVE
ALARM
Hdg. Diff
10°
Gyro 1
Gyro 2
GYRO
1
GYRO
2
GYRO
3
MAGN
COMP
246.8
246.7
246.8
247.0
12.8 kn
AUTO
SPEED
CAUTION Risk of erroneous operating conditions through inaccurate alignment
When the NAVITWIN IV is used in a system with the fiber-optic gyrocom-
pass NAVIGAT 2100 / NAVIGAT 3000:
At each new alignment (restart) of the NAVIGAT 2100 / NAVIGAT 3000,
make sure that the FOG aligns correctly, using valid speed and position
data.
The correctness of speed and position data must always be confirmed at
the respective FOG CDU each time a new alignment is carried out.
Note
Upon power-up, the NAVITWIN IV will activate the heading source which
was active when the device was last powered down.
If no valid heading is available from this source, an alarm is raised and
the operator must activate a different source.