Raymarine ST70+ User Manual

Chapter 3: Setup Information 51
Setting rudder gain
Rudder gain is a measure of how much helm the autopilot applies to correct course
errors – higher settings mean more rudder is applied. By adjusting the rudder gain you
can change the autopilot steering characteristics.
To adjust the rudder gain:
1. Use the Preliminary procedure above to
display the
Rudder gain page.
2. Scroll to set the required rudder gain value.
3. Press
OK to save the setting and return to the
Drive settings menu.
Setting counter rudder
Counter rudder is the amount of rudder the autopilot applies to try to prevent the boat
from oversteering. Higher counter rudder settings result in more rudder being applied.
To adjust the counter rudder:
1. Use the Preliminary procedure above to
display the
Counter rudder page.
2. Scroll to set the required counter rudder value.
3. Press
OK to save the setting and return to the
Drive settings menu.
Setting rudder damping
If a rudder reference transducer is fitted, you can set the autopilot rudder damping to
prevent autopilot ‘hunting’, i.e. continuously moving the steering backwards and
forwards by small amounts.
To adjust the rudder damping:
1. Use the Preliminary procedure above to
display
Rudder damping page.
2. Scroll to set the required counter rudder value.
3. Press
OK to save the setting and return to the
Drive settings menu.
Setting AutoTrim
AutoTrim determines how quickly the autopilot
applies ‘standing helm’ to correct for trim changes, caused, for example, by changes
in the wind load on the superstructure, or an imbalance of engines.
Increasing the AutoTrim level reduces the time the autopilot takes to return to the
correct course, but makes the boat less stable. If the autopilot:
• Gives unstable course keeping and the boat ‘snakes’ around the desired course,
decrease the AutoTrim level.
• Hangs off course for excessive periods of time, increase the AutoTrim level.
If you need to adjust AutoTrim, do so by changing by just one level at a time and use
i
D11320-1
Press OK to accept
Rudder Gain
3
Rudder gain defines the amount of rudder
applied to correct the vessel’s course.
i
D11321-1
Press OK to accept
Counter Rudder
5
The rate of return of the rudder once on
the new heading.
i
D11322-1
Press OK to accept
Rudder Damping
5
Prevents the rudder from oscillating.
85024_1.book Page 51 Tuesday, January 27, 2009 11:31 AM

Raymarine ST70+ Specifications

General

Display Type	LCD
Waterproof	Yes
Waterproof Rating	IPX6
Interface	NMEA 2000
Power Supply	12V DC
Backlighting	Yes
Network	NMEA 2000
Input Voltage	10-32V DC
Dimensions	110mm