Mounting Page
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Document id: 7000 108-011 A2
2.16.3.4.2 No ROT available
If no ROT information is available, the AIS will transmit default
values indicating not available. ROT data will not be derived from
COG information.
2.16.3.4.3 ROT sensor fallback conditions
The R4 Transponder automatically selects the ROT source with the
highest priority available. The priority scheme is defined by the AIS
standard (Ref. [5]).
2.16.3.5 Log
(VBW)
If a Bottom Track (BT) Log (hereafter referred to as Speed Log) for
Speed Over Ground (SOG) is available, it shall be connected to the
R4 Transponder.
The R4 Transponder will derive Course Over Ground (COG) from
this information.
Note that the R4 Transponder needs heading information to be able
to derive SOG and COG from Speed Log data. The R4 Transponder
will use the Speed Log as source for SOG and COG as long as
heading information is available.
If heading information is not available, Speed Log data will not be
used. In this case the R4 Transponder will use the position sensor as
source for SOG and COG.
2.16.4 Long Range equipment interface
2.16.4.1
Long Range communication system
The AIS’ Long Range function needs a compatible long-range
communication system (e.g. Inmarsat-C or MF/HF radio).
If this is available, a connection between that communication system
and the R4 Transponder can be made. This connection is needed to
activate the LR function of the AIS. Its input/output port must meet
the requirement of IEC 61162-2.
2.16.4.2
Long Range function
The Long Range reply can be set in either:
!
automatic mode (AUTO)
!
manual mode (MANUAL) or
!
manual mode external application (EXT APPL).
The Long Range reply, when in AUTO mode, is made as soon as a
request is received on the Long Range communication port.
The Officer on the Watch must approve the Long Range reply,
when in MANUAL mode, by a means of pressing a keyboard
button on the display before the reply is performed.
