Raymarine autopilot control unit - Manual (Page 63)

46 ST7000 Plus Autopilot Control Unit Owner’s Handbook
AutoTrim
The AutoTrim level setting determines the rate at which the autopilot
applies “standing helm” to correct for trim changes caused by varying
wind loads on the sails or superstructure.
The settings are:
Setting Effect Recommended for:
OFF No trim correction
1 Slow trim correction Heavy displacement vessels,
with full keel or transom rudder.
2 Medium trim correction Heavy displacement vessels.
3 Fast trim correction Some planing and moderate to light
displacement vessels.
4 Super fast correction Fast planing power vessels
Default: for Pilot Type Displacement 2
for Pilot Type Semi-Displacement 3
for Pilot Type Planing 3
for Pilot Type Sterndrive 3
The default setting should provide optimum performance with the
Course Computer. However, an incorrect rate of trim application may
result in poor course-keeping due to autopilot instability, depending on
the dynamic stability of the vessel.
After gaining experience with the Course Computer, you may wish to
change the setting. The effect of the setting must be evaluated while
under sail.
• Decrease the AutoTrim level if the autopilot gives unstable course-
keeping or excessive drive activity with a change in the heel angle.
• Increase the AutoTrim level if the autopilot reacts slowly to a
heading change due to a change in the heel angle.
• For systems without a rudder reference unit, these settings have no
effect and trim is set to level 3.
Power Steer
Power steer selects the Joystick mode of operation: Proportional or
‘Bang-Bang’.
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