Glossary | 111
SimNet Class 1 products – Simrad products that are
SimNet controllers, i.e. they have an appropriate display
and routines that can set up and control the SimNet.
SimNet Class 2 products – Simrad products that do not
contain a SimNet controller. When connected to SimNet
they will automatically pick the first available source on
SimNet and lock onto that. When a Class 1 product is
added to the Simrad Group, Class 2 products will
automatically subordinate themselves to the Class 1
source selection.
SimNet Group – A number of Simrad products that are
selecting and sharing the same data sources via the
SimNet network.
SimNet Source – Any product or device directly
connected to SimNet or NMEA2000, or interfaced to
SimNet via NMEA0183 or Robnet2.
SOG - Speed over ground is the actual speed of the
vessel relative to the ocean floor.
True bearing – Bearing relative to true north; compass
bearing corrected for compass error.
True heading – Heading relative to true north (the
meridian).
VMG – Velocity Made Good. A vessel’s true progress
towards a waypoint taken into consideration all factors
like leeway and current.
Waypoint - A discrete point, stored in a navigator,
located on the surface of the earth. Normally this point
will be identified by Lat/Lon coordinates although in some
systems it may be shown by T.D.'s.
XTE - Cross Track Error - Used to identify a vessel’s
position relative to a straight line drawn between two
waypoints. The amount the vessel is off to the left or to
the right of this line is known as the Cross Track Error. It
is normally displayed in thousands of a nautical mile,
equal to 6 ft or 1.85 m.
