Sitex SP38 Autopilot, Installation And Operation Manual

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Sitex SP38 Installation and Operation Adanced Operation
Document PN 29010101 V2r0
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Advanced Operations
This chapter describes the advanced modes of operation and features of a P-Series system,
and shows you how to use them.
WORK Mode
WORK mode is a special mode, for use in conditions that are different than normal autopilot
operation. Some prime examples are dragging, trawling, and pair trawling. It is also useful for
towing or when traveling at very slow speeds. WORK mode can be activated in either AUTO
or NAV mode. You can even switch from AUTO to NAV mode or vice-versa, while WORK
mode is active.
Initial set up of WORK
mode is easily accomplished. Only two parameters need to be
adjusted: a Work Trip Point and the Rudder Scaling Factor. Some other parameters can be
used to monitor and fine-tune the operation of WORK
mode.
The autopilot has an automatic Off-Course Alarm that will be activated should the boat fall off
the Commanded Heading by more than 20°. There is a 30 second delay on this alarm.
Automatic WORK Mode
Although WORK mode can be used manually, it works best if a valid NMEA source for the
boat's speed is also interfaced to the autopilot. The speed source must also be properly
configured (in the Auto menu, see page 127). With a valid NMEA speed source, WORK
mode can be engaged automatically when the boat’s speed falls below the Work Trip Point,
and disengaged when the boat’s speed increases beyond the Work Trip Point.
To use Automatic
WORK mode, first go into either AUTO or NAV mode. Then press and
hold the WORK button for approximately 1 second, until a confirming beep is heard. A small
letter `W´ will appear beside the bigger mode-indicator letter (`A´ or `N´) in the upper left
portion of the LCD screen, to indicate that the WORK
mode feature is enabled.
If the boat’s speed is above the Work Trip Point, the `W´ will flash slowly, about once per
second, indicating that WORK
mode is enabled – but not yet engaged. If the `W´ appears
continuously (not flashing), the boat speed is below the Work Trip Point, and WORK mode is
actually engaged.