Simrad Robertson AP9 Mk3, Instruction Manual, Page: 30 / 202

Robertson AP9 MK3 Autopilot
2-2
20169223D
2.3 Mode selection
Together with the OFF-button and the 3 mode buttons, this section
also contains an alarm buzzer and ALARM RESET-button.
HELMSMAN (Power ON)
The HELMSMAN button serves two purposes. It switches on the
autopilot and selects manual steering mode. In this mode the course
display gives a digital read-out of compass heading, while the vessel
can be steered manually by helm or steering lever(s).
AUTOPILOT
The AUTOPILOT-mode is used under normal conditions when the
boat is steered automatically on a pre-set course.
When the AUTOPILOT-button is pressed, the autopilot selects the
current vessel heading as "course to steer".
Any difference between course to steer and the vessel's actual
heading will then be shown as a bargraph in the bargraph display.
One bar equals one degree.
The autopilot uses the activated heading sensor unit, selected from
the COMPASS SELECT button to calculate the difference between
course to steer and actual ships heading. Rudder command signals
are then based on steering parameter settings.
Rudder commands are indicated by an arrow to left or right in the
bargraph display depending upon which direction the autopilot
commands the rudder to move. These arrows do not appear when
the autopilot output signal is analogue voltage. The “Debug” rudder
angle may show a random number as no rudder feedback is
connected.
For the
± 10V analogue control signal, a separate rudder control
system moves the rudder to match the rudder angle command.
NAV. MODE
NAV.-mode is used when a navigation receiver is connected to the
autopilot for automatic "waypoint" steering.
When the NAV-mode is selected, the AP9 MK3 automatically
monitors the signals from the navigation system. If the signals are
absent or in a wrong data format, an alarm will be given to alert the
operator. See page 2-15: Navigational Steering.
OFF
The autopilot is switched off by pressing the OFF-button for 2
seconds, during which time the alarm will sound. The alarm ceases