Sitex SP38 Autopilot, Installation And Operation Manual

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Sitex SP38 Installation and Operation
Document PN 29010101 V2r0
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Adjust Seastate for Hi Speed
1. To set Seastate, switch to AUTO mode, and then watch the Port and Starboard
rudder movement arrows at the ends of the screen’s RAI bar. In normal conditions,
there should be rudder movement about 15% to 20% of the time.
2. If the autopilot is over-active, increase the Seastate until the arrows blink less
often. If the autopilot is under-active, decrease the Seastate.
Adjust Rudder Gain, Counter Rudder, Turn Rate and Seastate for Lo Speed
1. Adjust boat speed to what will be your lowest normal “low speed” – that is, the
lowest speed at which you will ever choose to use the autopilot (for most vessels,
a good speed to do the “low speed” adjustments is at or below the maximum
speed in a Speed Control Zone or “no wash” area – usually 5 Knots).
2. Bring up the Auto menu, highlight “Parameter Set” and select “Lo”.
3. Repeat the steps in the Hi speed Rudder Gain and Counter Rudder adjustment
process discussed previously (the starting value to use for Lo speed Rudder Gain
is the factory-default of 8).
4. Adjust the Lo speed Turn Rate setting to suit your preference. Make a few
Course changes of 40° or more to ensure that the rate of turn is comfortable.
5. Adjust the Lo speed Seastate setting to suit your preference.
Adjust Speed Trip Point
1. Bring up the Auto menu, and set the Trip Point speed to something mid-way
between the speeds used for setting the Hi and Lo speed parameters in the steps
discussed previously. This should be a speed you will never travel at for any
length of time – for example, in a planning-hull boat, it would be a speed just a little
bit less than where the hull starts to get up on the step.
2. Bring up the Auto menu, highlight “Parameter Set” and select “Auto”.
3. In AUTO mode, change the boat speed back and forth between the Lo and Hi
speeds you will normally use. The vessel should continue to maintain a straight
Track along the heading you are on, and you should see that the display’s
Parameter Set indicator changes back and forth between “L Auto” and “H Auto” as
you change speeds.
Adjusting for Rougher Sea Conditions
The primary desire of any autopilot user is that the system steers the boat safely and
accurately, across all sea conditions.
Adjusting the steering parameters in calm conditions – as you did during the initial part of
the Sea Trials, above – gives a base reference for all other conditions. After doing those
adjustments, you can then venture into rougher sea conditions.
Take all the time necessary to ensure that you are getting the best performance from your
autopilot!
Installation