Chapter 2: SPX system settings
31
The default AutoTrim is set as part of the AutoLearn process (see
page 14
).
If you need to change the setting, increase the AutoTrim one level at a time and use
the lowest acceptable value:
•
If the SPX system gives unstable course keeping or excessive drive activity with a
change in the heel angle, decrease the AutoTrim level.
•
If the SPX system reacts slowly to a heading change due to a change in the heel
angle, increase the AutoTrim level.
•
If the AutoTrim level is too high, the boat will be less stable and snake around the
desired course.
Response level
This sets the default SPX system response level setting. The response level controls
the relationship between course keeping accuracy and the amount of helm/drive
activity. You can make temporary changes to response during normal operation
(see
your
Pilot Controller
Operating Guide
for details).
Turn rate limit
This limits your boat’s rate of turn under SPX system control.
Off course angle
This screen determines the angle used by the OFF COURSE alarm (see your
Operating Guide
). The OFF COURSE alarm operates if the pilot strays off course by
more than the specified angle for more than 20 seconds.
Setting
Effect
AUTO TRIM OFF
No trim correction
AUTO TRIM 1 to 6
Auto trim applied:
1 = Slowest, 6 = Fastest
Screen Text
Options
RESPONSE
Range = 1 to 9
Levels1 to 3 minimize the amount of pilot activity. This conserves
power, but may compromise short-term course-keeping accuracy
Levels 4 to 6 should give good course keeping with crisp, well con-
trolled turns under normal operating conditions
Levels7 to 9 give the tightest course keeping and greatest rudder
activity (and power consumption). This can lead to a rough passage
in open waters as the SPX system may ‘fight’ the sea.
Screen Text
Range
TURN RATE
1° to 30° per second in 1° steps
Screen Text
Range
OFF COURSE
15° to 40° in 1° steps
81307_1.book Page 31 Wednesday, December 19, 2007 11:17 AM
