Simrad NAC-D, Commissioning Manual

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If the autopilot is not keeping the heading satisfactorily or not
making the turns satisfactorily, you may now either try the Autotune
function or go directly to manual tuning.
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Note:
If the vessel is more than approximately 30 m/100 ft or
has a very high cruising speed it may be unpractical to perform
Autotune. It is then suggested to proceed with manual tuning.
Autotuning
When performing an autotune, the vessel will automatically be
taken through a number of S-turns. Based on the vessel behavior,
the autopilot will automatically set the most important steering
parameters (Rudder gain and Counter rudder).
• Stabilize the vessel on a heading and set the speed between 5-10
kn, then select
Autotune
.
- The autopilot will now switch to AUTO mode and take control
of the vessel.
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Note:
Autotuning can be stopped at any time by pressing the
STBY
key on the autopilot controller.
The autotuning takes approximately 3 minutes to complete. When
completed the autopilot automatically switches to Standby mode,
and the rudder must be controlled manually.
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Note:
All parameters that are set during autotuning can be
manually adjusted. For optimal steering performance it is
recommended to manually adjust the steering parameters after
running the autotune.
Manual tuning
Rudder gain and Counter rudder can be manually adjusted.
• Stabilize the vessel on a heading and set the speed in the middle
of the profile range (well clear of the transition speed) to avoid
profile switching during tuning. Then activate the
Rudder gain
option. Adjust the value according to the descriptions below.
• If required, adjust slightly the
Counter rudder
option.
Sea trial | NAC™ -D Commissioning manual
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