Sitex SP38 Autopilot, Installation And Operation Manual

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Sitex SP38 Installation and Operation
Document PN 29010101 V2r0
- 4 8 -
The alternative circuit, using Switched B+ ( SW'D B+ ) as the alarm output:
Figure 24 – External Alarm, SW'D B+ Output – with Power Fail Option
Speed Mode and Timing Outputs (J12, MISC I/O)
The SP38 SPU outputs two status signals on the
J12 – MISCELLANEOUS
connector.
The receptacle is supplied with a 10-pin mating plug.
In addition, a 1 pulse per second (PPS) timing signal is output
on
J12
. It is about 5%
accurate, and is meant for general-purpose use. For example, some brands of Radar and
other navigation equipment require a “1 PPS” timing signal for proper operation.
These two status signals indicate:

If the system is operating with the Hi or Lo speed steering parameters in effect,
in
AUTO
or
NAV
modes

If the system is operating in WORK mode
The status signals are meant to be used to allow indication of those conditions on an external
alarm or indicator. While both conditions are indicated on the Control Head’s LCD display, but
it is also sometimes useful to have them alert with an external alarm or lamp at locations other
than where the Control Head is located.
These two outputs can also be used to control automatic deployment (and retrieval) of
external “stabilizer” equipment, to enhance the vessel’s steering and stability when it is
moving at a slow speed, or when WORK mode is in effect. In both these situations, the boat is
moving slowly, and so there is not as much steerageway (i.e., less water flowing over the
rudder, so it does not generate as much sideways force).
Installation