Rudder Gain; Checking; Adjusting - Raymarine SPX-5 Installation & Setup Manual

42

Rudder gain

Boats can vary widely in their response to helm, and by adjusting the rudder gain you
can change the SPX-5 Wheel system's steering characteristics. Rudder gain is a
measure of how much helm the SPX-5 Wheel system applies to correct course errors
– higher settings mean more rudder is applied.

Checking

Complete the following test to determine whether the rudder gain is set correctly:
1. Set RESPONSE to level 5 (see above).
2. Motor your boat at a typical cruising speed in clear water.
It is easier to recognize the steering response in calm sea conditions where wave
action does not mask steering performance.
3. Press auto to enter Auto mode, then alter course by 40°:
• If the rudder gain is adjusted correctly, the 40° course change should result in
a crisp turn followed by an overshoot of no more than 5°
• If the rudder gain setting is too high, the 40° course change will result in a
distinct overshoot of more than 5° and there may be a distinct 'S' in the course,
as at (A)
Correct this oversteer by reducing the rudder gain setting.
• If the rudder gain is too low, the boat's performance will be sluggish – it will take
a long time to make the 40° turn and there will be no overshoot (B)
Correct this understeer by increasing the rudder gain setting.

Adjusting

To adjust the rudder gain:
1. Access the RUDD GAIN screen in Dealer calibration (see page 51 ).
2. Use -1 or +1 to adjust the rudder gain.
3. Hold down standby for 2 seconds to save the changes.
4. Press auto to check the SPX-5 Wheel system performance in Auto mode.
SmartPilot X-5 Wheel Installation & Setup Guide
heading
Rudder gain
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Rudder gain
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Correct
rudder gain
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