Specifications

16
IMPORTANT
It is important to remember that the compass is a vital part of the autopilot system. Locating it properly,
particularly on steel hulled vessels, is essential to ensure proper operation of the autopilot. We
recommend that the services of a qualified compass adjuster be used to select the best installation
location and to compensate the compass properly for deviation, including that caused by heeling error.
Care must be taken not to place compensating magnets too close to the compass, as this will cause
the Fluxgate Sensor, mounted underneath the compass, to read incorrectly. To correct compass
deviation on steel vessels, or on other vessels with magnetic compensating problems due to
interference from adjacent iron masses such as an engine block or winches, the use of a pair of 3-1/4
inch (83 millimetre) Compensating Quadrantal Spheres is recommended.
Figure 4
-Test Points
MOUNTING THE SENSOR TO NON-
STANDARD COMPASSES
The fluxgate sensor supplied with the
autopilot can be mounted to a wide
variety of "externally gimballed"
compasses. The sensor should not be
mounted to "internally gimballed"
compasses (where the compass card is
gimballed and the bowl of the compass is
not), because the compass card does
not remain parallel to the sensor when
the vessel rolls or pitches, resulting in
large errors between the compass and
autopilot.
Mounting the sensor above the compass
reduces the possibility of compensating
magnets interfering with the operation of
the sensor, but also reduces the visibility
of the compass if it is to be used as a
steering compass.
Remove the rear cover from the
autopilot. Fasten a pair of voltmeter
probes between the SIN and +2.5V
testpoints on the Processor Board
(see
figure 4)
.
Turn the master select switch on the
autopilot to the
STANDBY
position. Hold
the sensor either above or below the
compass, and rotate it until a maximum
level is observed on the voltmeter.