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

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056360/E NAVITWIN IV
1-4 Standard System Configurations
1.3 Standard System Configurations
The NAVITWIN IV with Switch-Over Unit type 4932 is an integral part of
Sperry Marines standard single, dual and triple gyrocompass configura-
tions with NAVIGAT X MK1, X MK2 gyrocompasses and NAVIGAT 2100
NAVIGAT 3000 FOGs.
Single NAVIGAT Gyrocompass/TMC System
In a single gyrocompass system with the NAVIGAT X MK 1, X MK 2 or
NAVIGAT 2100 / NAVIGAT 3000, the NAVITWIN IV‘s main function is to
provide an independent magnetic compass heading source (TMC func-
tion).
In case of failure of the gyrocompass, the magnetic compass may be
used as emergency heading reference for repeaters and other external
equipment.
The NAVITWIN IV may receive an analogue sine/cosine signal from the
Sperry Marine fluxgate sensor, type 4863, or may receive NMEA head-
ing data from an electronic compass.
The NAVITWIN IV applies magnetic variation to the raw sensor value
and provides a correction table to compensates for the sensor‘s devia-
tions from the magnetic compass heading.
The “heading diff.” alarm function permits to monitor the gyrocompass
against the magnetic compass heading. The “off heading” alarm func-
tion permits to monitor the difference between the actual heading and
the heading to steer received from a heading control system.
Operating parameters entered at the NAVITWIN IV are transmitted to
the NAVIGAT gyrocompass. In turn, alarms generated by the compass
are indicated and may be acknowledged at the NAVITWIN IV.
Figure 1-1 below illustrates how the active source selection at the
NAVITWIN IV controls the distribution of data from the gyrocompasses,
via the Switch-Over Unit, to external equipment.
Figure 1-1:
Data distribution in
a NAVIGAT *single gyro-
compass / TMC system
* The NAVIGAT 3000 is as well representative for the NAVIGAT 2100,
not shown in the above figure.
GYRO
1
MAGN
COMP
246.8
247.0
Switch-Over Unit
NAVITWIN IV
source selection
to external
equipment
mag. hdg.
Magnetic
Compass
NAVIGAT X MK 1 ,
NAVIGAT X MK 2 or
NAVIGAT 3000
G/M