Raymarine ST600R, Руководство пользователя

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ST600R Autopilot Control Unit
Checking the Rudder Gain
The factory setting for rudder gain will provide stable control for
initial sea trials. However, vessels can vary widely in their response
to the helm, and further adjustment to the rudder gain may improve
the autopilot’s steering characteristics.
It is important to ensure that rudder gain is set correctly on high-
speed craft. Incorrect adjustment will lead to poor steering
performance and is dangerous at high speeds.
The following test will determine whether the rudder gain is set too
high or too low.
1. In clear water and with the autopilot in Auto, alter course to
starboard by 40° by pressing the
+ 10
key four times.
• At cruising speeds, course changes of 40° should result in crisp turns
followed by an overshoot of no more than 5°. If this occurs the
rudder gain is adjusted correctly.
• An excessively high rudder setting results in oversteer. This is
recognised by a distinct overshoot of more than 5° (A). This
condition can be corrected by reducing the rudder gain setting.
• Similarly, an insufficient rudder control setting will result in
understeer which gives sluggish steering performance (B). If the
vessel takes a long time to make the turn and there is no overshoot
then the rudder setting is too low.