Raymarine ST6000 Service Manual page 91

magnetic field at higher latitudes which has
the effect of amplifying rudder response on
northerly (southerly) headings.
Rudder Gain Adjustment (Sail) It is not
normally necessary to adjust the autopilot
gain setting once the correct level has been
established during initial sea trials.
Depending on the yachts individual steering
characteristics a change of one level may
improve course keeping accuracy when
going from northerly to southerly (increase)
or southerly to
headings.
The effect may be judged by carrying out a
sea trial in smooth water conditions and
observing the results.
Note: The effect is reversed for the
southern hemisphere.
Rudder Gain Adjustment (Powercraft) The
tendency towards
heading instability is more obvious in high
speed craft and can be corrected by a
reduction in the rudder gain setting. At
speeds in excess of 30 knots a reduction of
two levels can be required on headings
between 315°
hemisphere) or 135° and 230° (southern
hemisphere).
Two options are available to control this:-
• Manual (Low speed and displacement
craft) The rudder gain control may change
by one level when going from northerly to
southerly (increase) or southerly to northerly
(decrease) headings.
The effect may be judged by carrying out a
sea trial in smooth water conditions and
observing the results.
Note: The effect is reversed for the southern
hemisphere.
• Autoadapt (High speed planing craft)
The ST6000 can be set to automatically
reduce the effects of Northerly heading
instability. This feature is selected in
calibration mode by entering the Latitude
(see Installation Handbook, Calibration,
section on 'Auto Adapt'). When selected the
ST6000 automatically adjusts the Rudder
Gain depending on the compass heading,
removing the need for manual adjustment.
northerly (decrease)
northerly (southerly)
and 045° (northern
Rudder Gain/Speed
(Powercraft)
High speed planning craft exhibit very
different steering characteristics when on
and off the plane. As a result it is generally
necessary to adjust the Rudder Gain setting
when going from displacement speed to
planing speed or vice versa. Two options
are available to achieve this:-
• Automatic
When the ST 6000 is used with an
Autohelm ST50
Tridata. Rudder
automatically with boat speed. There should
be no need for any manual adjustment.
• Manual
(No ST50 Speed/Tridata) The Rudder Gain
setting may be increased by one or two
levels when dropping from planing speed to
cruise speed and decreased by the same
amount when returning to planing speeds,
Note: It is important to make the gain
adjustment after dropping to displacement
speed and before returning to planing
speed.
Note: The adjustment of Gain with boat
speed is normally only required for high
speed planing powercraft.
Unsatisfactory Steering Performance
If the ST6000 has been installed and set up
in accordance with the instructions in the
Installation Manual it will provide excellent
steering performance over a wide range of
conditions.
If performance drops but the autopilot is still
working correctly, the following simple
checks should find the fault:-
• Has
a magnetic
introduced near the fluxgate compass? i.e.
anchor, chain,
loudspeaker, tools. generator etc. Check
that the autopilot compass heading still
corresponds with the steering compass.
• Are all fuses intact, circuit breakers
engaged?
• Are all screw connections tight and free
of corrosion.
SeaTalk Service Manual
Autohelm Autohelm
Autohelm Autohelm
Adjustment
Speed Instrument
Gain is adjusted
influence been
radio equipment,
or
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