P3, Counter Rudder [Crd]; P4, Damping Of Wind [Wse]; P5, Automatic Trim Calibration [Atc] - Nexus AUTOPILOT Installation And Operation Manual

SETUP 6 SETUP / CALIBRATION
This setting is a combination of yaw dead-band (compass sensitivity)
and compass damping. The minimum setting may only be used under
calm sea conditions to avoid unnecessary rudder correction due to
compass acceleration errors.
Smaller boats and high speed boats, which are subject to more accel-
eration in lighter seas will have to use higher settings. Larger and more
stable boats can use lower settings since there is less compass distur-
bance.
Default setting should work on most boats in light to moderate sea con-
ditions. Following seas, no matter how rough, may require lower set-
tings to catch course error trends quickly in order to minimise excessive
yaw.

5.3.4 P3, Counter Rudder [CRD]

Possible settings are [0] = Minimum to [9] = Maximum.
Set by the APC routine.
This setting senses the rate of change of heading and gives additional
rudder corrections if the boat is rapidly falling off course, and backs off
the rudder as a boat approaches the desired heading. Its effect is to
rapidly catch the tendency to yaw in a quartering sea, provide initially
high rudder control when making a large course change and to deceler-
ate the swing of the bow, as a boat approaches the desired course.
Course holding with heavy and difficult to steer boats, is greatly im-
proved , when using this feature. Too little counter rudder, will allow the
boat to overshoot on large course changes. Too much will cause un-
necessary rudder corrections and a tendency to stop short of coming to
a new course, requiring several successive corrections before easing up
to the new heading.
To optimise counter rudder, initially set it to minimum and adjust the
rudder (see, [RUD] 5.3.2). Increment the counter rudder one step at a
time, while testing 40 course changes, until the boat achieves an over-
shoot of 1 to 2 or less. Remember, that any air in the hydraulic sys-
tem will prevent precision control.

5.3.5 P4, Damping of wind [WSE]

Possible settings are [0] = Minimum to [9] = Maximum. Default setting
is [2].
Damping of wind transducer. The factory default setting should be ade-
quate. In very heavy weather or unstable wind conditions, unnecessary
corrections may be minimised by increasing the setting.

5.3.6 P5, Automatic Trim Calibration [ATC]

Possible settings are [0] = Minimum to [9] = Maximum.
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