Navitron NT888G MK2, Руководство по эксплуатации

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NT888G MK2 AUTOPILOT OPERATING MANUAL
2.27 SOG Speed Data Input (Speed over the Ground) … (Continued).
(When operating in the Track Control Mode based on complex $xxHTC data received
from an Approved Track Control System, all necessary parameters – including SOG –
will be available from the Track Control System). In the event that SOG data is
absent, or fails, an audible alarm and display –
No radius control – will be displayed.
If SOG data is present but the SOG is too slow to sustain the specified
RADIUS of
TURN , audible and visual alarms will result – Low speed .
2.28 Draft Input (Laden State).
Draft Input data is an Adaptive operating mode parameter but its absence will not
prevent Adaptive Autopilot calibration and operation provided STW Speed input data
is available.
However, if draft Input data was present in previous/original Adaptive calibration
procedures, it’s subsequent absence or failure will generate an audible alarm and
display message
‘HCS fault: Draft adaptive control unavailable, no data’ .
Ongoing Speed Adaptive operation will still be possible but the audible alarm will
persist until/unless Draft data is restored or the audible alarm is muted by 5 second
operation of the TEST/OFF key.
NB. If the alarm is muted in this manner – ALL audible alarms will be muted.
2.29 Calibration of Adaptive Steering Performance vs Speed.
The Speed Adaptive operating mode is based on the ‘capture’ of known steering
characteristics over a range of operating conditions which can be used as the initial
(start) conditions when the Autopilot is engaged.
Once engaged, further adaptive measures are taken to automatically adjust control
parameters geared to changes in speed, draft and sea state etc. to maintain optimum
steering performance.
In addition, Override Controls are also calibrated against speed to ensure that
potentially dangerous angles of rudder are not inadvertently applied – particularly
where High Speed Craft (HSC) operation is involved.
NB. Where possible, it is strongly recommended that Adaptive data is taken at 3
speed levels (although 2 will be accepted). The speeds should reflect minimum likely
for Autopilot Control, Normal working/cruising speed and maximum speed.
2.29 (i) Adaptive Calibration Input Requirements:-
(a) Optimum steering performance should have been assessed and
achieved by manual adjustment of PID controls via the CONTROLS
menu per sections 2.19 to 2.25.
(b)
Speed Through the water (STW) input data must be available (An alarm
will be generated if Adaptive calibration or mode entry is attempted in
the absence of STW input data).