Seatrials - Simrad AP70 Operation Manual

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 Note:
The Thruster inhibit limit will only apply when speed source is Log or SOG, not if the
speed is set manually.
• Rang: 1 - 40 (kn)
• Default: 6 (kn)
Low speed limit
Sets the limit for the low vessel speed alarm.
An alarm occurs when the vessel's speed goes below the selected limit.
• Range: 1 - 20 (kn)
• Default: 1 (kn)
Init rudder
Defi nes how the system moves the rudder when switching from power steering to an
automatic mode:
- Midships moves the rudder to zero position.
- Actual maintains the rudder off set, and use this as trim value (bumpless transfer)
 Note:
Actual is only available with rudder feedback signal available.
• Default: Midships

Seatrials

Compass calibration
All magnetic compasses must be calibrated as part of the autopilot seatrial procedure.
Before the compass calibration is started, make sure that there is enough open water around
the vessel to make a full turn.
The calibration should be done in calm sea conditions and with minimal wind to obtain good
results. Follow the on-screen instruction, and use about 60-90 seconds to make a full circle.
1. Start the calibration by selecting the Calibrate button in the device calibration dialog
2. Follow the online instructions
During the calibration, the compass will measure the magnitude and direction of the local
magnetic fi eld.
• If the local magnetic fi eld is stronger than the earth's magnetic fi eld (the local fi eld is reading
more than 100%), the compass calibration will fail
• If the local fi eld is reading more than 30%, you should look for any interfering magnetic
objects and remove them, or you should move the compass to a diff erent location. The (local)
fi eld angle will guide you to the local interfering magnetic object.
 Note:
Calibration must be made on the compass that is active for the autopilot. If another
model compass from Simrad or another manufacturer is installed, refer to the calibration
instruction for that compass.
 Note:
In certain areas and at high latitudes the local magnetic interference becomes more
signifi cant and heading errors exceeding ±3° may have to be accepted.
System confi guration | AP70/AP80 Operator Manual
Lubber line
20%
10°
Magnitude of local fi eld in % of
earth's magnetic fi eld.
Direction of local fi eld with respect
to lubber line. It can also be on the
reciprocal.