Konsberg AIS 200, Installation Manual

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Kongsberg AIS 200 Installation Manual, rev. 2 Installation
3.11 GPS antenna
3.11.1 Mechanical installation
The GPS antenna included in the AIS 200 system is used for time synchronisation and
computation of backup position fix. In addition to this GPS antenna, the AIS 200 should be
connected to the vessel’s main GPS system at the rear of the Mobile Unit. Sensor input 1-3
may be used.
Optimum location of the GPS antenna is important to ensure continuous track of all visible
GPS satellites. The following should be taken into consideration during installation:
The GPS antenna must be installed where it has a clear view of the sky and thus the
objective is to see the horizon freely through 360 degrees with a vertical observation of 5
to 90 degrees above the horizon.
•
•
•
Small diameter obstructions, such as masts and booms, do not seriously degrade signal
reception but such objects must not eclipse more than a few degrees of any given bearing.
The antenna should be located at least 3 metres away from and out of the transmitting
beam of high power transmitters (S-band radar and/or Inmarsat systems). This includes the
ship's own AIS VHF antenna if it is located separately.
Refer figure on page 21.
Use the supplied antenna mounting kit when mounting the antenna. Appropriate crimping
tools must be used.
3.11.2 GPS antenna offset arms
C D
B
A
The mounting location for the internal GPS antenna and for the
main GPS antenna connected to the AIS 200 system, needs to be
input to the AIS 200 as a part of the configuration settings. The
figure shows the offset arms that have to be configured.
Refer
Entering static data , pages 36 and 94.
3.11.3 Checking the antenna cable
After the mechanical and electrical installation is completed, the coaxial cables should be
checked for short circuit between centre conductor and shield (ground) with the antenna
disconnected. If not short-circuited, the antenna cable could be connected to the Mobile Unit.
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