Si-tex SP38, Инструкция по установке и эксплуатации, Страница: 138 / 193

Sitex SP38 Installation and Operation Advanced Operations
Document PN 29010101 V1r0
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Seastate
The Seastate control tells the autopilot how much deviation from the set course allow before
taking corrective action. This deviation is also called “Yaw.”
Seastate should be set according to sea conditions. As conditions worsen, the Seastate
setting can be increased. This can result in slightly decreased steering performance, but will
improve and reduce the amount of rudder movement and strain on the steering system.
This parameter’s units are in total degrees on either side of the set course, so a value of 1 will
allow the vessel to change up to 0.5° of heading on either side of the set course before
bringing it back on course. The maximum value is 10°.
There is also an Automatic Seastate Control feature that will monitor and adjust the Seastate
setting for you. To activate this, highlight “Seastate” in the menu and turn the COURSE
CHANGE knob counter-clockwise until the value reads “A.”
There are two Seastate settings; one is for low speed operations (LO) and one is for high
speed operations (HI).
Turn Rate
Varying the Turn Rate parameter controls the maximum rate at which the vessel may make a
course change (in AUTO or NAV modes), return to its original heading after a dodge
manoeuvre, or execute a Special Turn. Factors such as speed, load, hull characteristics and
weather conditions may limit the maximum achievable turn rate.
This parameter’s units are in degrees per second. Up to 1.5 °/sec, the value increments by
0.1° per click of the COURSE CHANGE knob; between 2.0 °/sec to the maximum of
20.0 °/sec, it changes by 1° per click.
There are two Turn Rate settings; one is for low speed operations (LO) and one is for high
speed operations (HI).
Parameter Set
The SP38 gives you the ability to store two sets of steering parameters, labelled “Hi” (high)
and “Lo” (low). This allows for best performance under varying vessel speeds and/or loading
conditions.
The autopilot can be set manually to use either the Lo or the Hi settings. There is also a
selection for “Auto”. If Auto is chosen, the autopilot will automatically switch from Hi to Lo, or
vice-versa, depending on the vessel’s speed. For Auto to work, the autopilot must be
connected to an NMEA 0183 Navigation System that outputs speed information. The Speed
Trip Point discussed later, governs the point at which the switch is made.
When the SP38 is in AUTO or NAV mode, it always indicates which steering parameter set is
in effect. This is shown just to the left of the Rudder Angle Indicator, and consists of a small
box shape with either H for Hi or L for Lo in it. If the parameter is set to Auto, then the word
“AUTO” also appears in the box (
Figure 61 ).