About The Sea Trial Wizard; Important Sea Trial Wizard Considerations; Starting The Sea Trial Wizard; Performing The Sea Trial Wizard - Garmin GHP 20 Marine Autopilot System for Steer-by-Wire Installation Instructions Manual

about the Sea trial Wizard

The Sea Trial Wizard configures the fundamental sensors on the
autopilot, and it is extremely important to complete the wizard in
conditions appropriate for your boat.

Important Sea trial Wizard Considerations

Complete the Sea Trial Wizard in calm water. The nature of calm water
is relative to the size and shape of your boat.
• Ensure your boat does not rock while sitting still or moving very
slowly.
• Ensure your boat is not significantly affected by the wind.
• Keep the weight on your boat balanced. DO NOT move around
on the boat while completing any of the steps in the Sea Trial
Wizard.

Starting the Sea trial Wizard

Before you start the Sea Trial Wizard, you must drive to an open area of
calm water.
1. Turn on the GHP 20.
2. Select an option:
• If the Sea Trial Wizard starts automatically, proceed to step 3.
• If the Sea Trial Wizard does not start automatically, select Menu
> Setup > Dealer Autopilot Configuration > Wizards > Sea
Trial Wizard.
3. Select Begin.

Performing the Sea trial Wizard

1. Drive your boat to an open area of calm water.
2. Start the Sea Trial Wizard
3. Configure the planing RPM
4. Calibrate the compass (page
5. Perform the autotune procedure
6. Set north (page 12).
7. If necessary, set the fine heading adjustment

Configuring the Planing RPM

1. Note the RPM reading from the tachometer on the dashboard of
your boat at the point your boat transitions from displacement to
planing speed.
2. If the tachometer value does not match the value on the GHC 10,
use the arrows to adjust the value.
3. Select Done.

Calibrating the Compass

1. Drive your boat at slow/idle speed in a straight line.
2. Select Begin, and continue to drive in a straight line.
3. When instructed, turn the boat slowly clockwise, taking care to
make the turn as steady and flat as possible.
Turn slowly so that the boat DOES NOT list.
The GHC 10 displays a completion message when the calibration is
complete.
4. Select an option:
• If the calibration completes successfully, select Done.
• If the calibration fails, select Retry and repeat steps 1–3.
12
(page 12).
(page 12).
12).
(page 12).
(page 12).

Performing the autotune Procedure

Before you can perform the autotune procedure, you must have a large
stretch of open water available.
1. Adjust the throttle so the boat travels below planing speed.
2. Select Begin.
The boat performs a number of zigzag motions while the Autotuning
is in progress.
The GHC 10 displays a completion message.
3. Select an option:
• If the autotune completed successfully, select Done and take
manual control of the boat.
• If the autotune failed, adjust the throttle and select Retry
Autotune.
4. If autotune fails, repeat steps 1–3 until the autotune completes
successfully.
5. If the autotune procedure continues to fail after you reach maximum
cruising speed, reduce your speed to the initial autotune speed
and select Alternate Autotune to begin an alternate autotuning
procedure.

Setting north

Before you can set north, you must have at least 45 seconds of hazard-
free, open water available.
This procedure appears only if you connect an optional GPS device to
the GHP 20 (page 10), and the device has acquired a GPS position. If
you do not have a GPS device connected, you are prompted to set the
fine heading adjustment (page
1. Drive the boat in a straight line at cruising speed, parallel to the
prevailing wind and current, for 45 seconds.
2. Select Begin.
3. Select an option:
• If the calibration completed successfully, select Done.
• If the calibration failed, repeat steps 1–2.

Setting the Fine Heading adjustment

This procedure appears only if you do not have an optional GPS
device connected to the GHP 20
device installed on your boat that has acquired a GPS position, you are
prompted to set north instead
1. Using a handheld compass, identify north.
2. Adjust the fine heading setting until it matches north on the
magnetic compass.
3. Select Done.

Evaluating the Results of the autopilot Configuration

1. Test the autopilot at a slow speed.
2. If necessary, adjust the gain setting
3. Test the autopilot at a higher speed (normal operating conditions).
4. If necessary, adjust the gain and acceleration limiter settings.

testing and adjusting the autopilot Configuration

1. Drive the boat in one direction with the autopilot engaged (heading
hold).
The boat should not oscillate significantly; however, a small amount
of oscillation is normal.
12).
(page 10). If you do have a GPS
(page 12).
(page 13).
GHP 20 Installation Instructions