Raymarine ST5000+, Руководство пользователя

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ST5000 Plus Sterndrive & Hydraulic Autopilots
Checking the rudder gain
The factory set rudder gain level 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 particularly important that the rudder gain is set correctly on high-
speed craft. Incorrect adjustment will lead to poor steering
performance and is a dangerous condition at high speed.
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.
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