Raymarine Autohelm 4000, User Manual

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OPERATION
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BASIC PRINCIPLES
The following description of the
4000’s principle of operation
will help you to make full use of its
advanced features.
The powerful combination of a
compass and microprocessor control
provides “autolock” course selection
together with precise push-button course
adjustment.
Deviation from the set course is
continuously monitored by the sensitive
compass and corrective rudder is
applied to return the vessel to course. The
applied rudder is proportional to course
error at any time and thus when the
course is restored the rudder will be
neutralised.
When changes in vessel trim occur due
to variations in wind pressure or engine
throttle setting the course can only be
maintained by the application of
permanent rudder off-set (standing helm)
to restore balance. If permanent rudder
off-set is not applied to restore balance
the vessel will bear on to a new heading.
Under these circumstances the
4000 detects
that the original course is
not being restored and continues to apply
additional rudder off-set in the
appropriate direction until the vessel
returns to the original heading. Automatic
trimming capability ensures that the
originally set course is held irrespective of
any changes in balance that may occur
during the course of a passage.
The 4000’s computer also
continuously monitors the pattern of
applied rudder correction and can
distinguish unnecessary repetitive
corrections caused by pitch and roll of the
vessel from those necessary to maintain
the selected heading. The computer will
automatically neglect all unnecessary
corrections so that autopilot activity and
power consumption is continuously
optimised at minimum levels.
1 0
The deqree of control automation
KEYPAD OPERATION
made possible-by the computer
simplifies user control to a series push
operations.
Full control of the 4000 is
provided via a simple six button key pad.
The basic control functions are as
follows:
When the autopilot is switched on it
will always start up in Stand by mode. In
Stand by mode the wheel can be driven
4 0 0 0 )
- 1 0
0 0
STAND AUTO
Push once to engage the autopilot
to maintain the current heading or
push twice (within 2 seconds) to
return to the previous automatic
heading.
by pressing and holding down any of the
r course change buttons.
R E M O T E V A N E
Push to alter course to port or
starboard in increments of 1
and 10 degrees.
autopilot and return to Stand by
mode.
(The previous automatic heading
will be memorised).
STAND BY
Push once to disengage the . .