Airmar LB150 User Manual
Page 27
LB150 WeatherStation Technical Manual revision 0.013
Proprietary and Confidential
PRELIMINARY - DRAFT
24
NMEA 0183 TRANSMITTED SENTENCE
$WI
VWT
Summary
NMEA 0183 True wind angle in relation to the vessel’s heading, and true wind
speed referenced to the water. True wind is the vector sum of the Relative
(apparent) wind vector and the vessel’s velocity vector relative to the water along
the heading line of the vessel. It represents the wind at the vessel if it were
stationary relative to the water and heading in the same direction. Since LB150s
are not intended for use on boats, this sentence is not likely to be useful, but if
enabled and VHW sentence is received, it will work.
Syntax
$WIVWT,<1>,<2>,<3>,<4>,<5>,<6>,<7>,<8>*hh
Fields
<1>
Calculated wind angle relative to the vessel, 0 to 180°, left/right of
vessel heading, to the nearest 0.1 degree
<2>
L = left, or R = right
<3>
Calculated wind speed, knots, to the nearest 0.1 knot
<4>
N = knots
<5>
Wind speed, meters per second, to the nearest 0.1 m/s
<6>
M = meters per second
<7>
Wind speed, km/h, to the nearest km/h
<8>
K = km/h
Default State
Disabled, but when enabled, automatically prohibited until water speed is
provided via the NMEA 0183 input. Transmitted once per second when enabled
and not prohibited.
Notes
This sentence can be manually enabled or disabled via the $PAMTC,EN,VWT
command.