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Section 6 Parameter Settings
60
FT702LT Flat Front Wind Sensor Manual
6.4.26 WV NMEA: Query the Wind Velocity Reading
Command
Parameter
WV (NMEA)
Command
Syntax
SET Sensor:
N/A
QUERY Sensor:
$<listenerID>,WV?*<checksum><cr><lf>
$aa,WV?*hh<cr><lf>
FT702LT output:
$WIMWV,<angle>,R,<speed>,M,<status>*<checksum><cr><
lf>
$WIMWV,xxx,R,xxx.x,M,A*hh<cr><lf>
Parameters <angle>
000 to 359
measured wind direction in degrees relative to FT702LT datum
<speed>
000.0 to 050.0
measured wind speed (in meters per second)
000.0 to 097.2
measured wind speed (in knots)
000.0 to 180.0
measured wind speed (in kilometres per hour)
<units>
M
Indicates the wind speed is presented in metres/second
N
Indicates the wind speed is presented in knots
K
Indicates the wind speed is presented in kilometres/hour
< status >
0 to Z
Indicates whether an error condition was detected by the operating
system, such as out of range wind speed or incorrect signal level.
Any character other than ‘A’ (ASCII 41(HEX)) = error
Examples Example 1
The following example illustrates the NMEA wind velocity data format. The example
shows the FT702LT output in m/s with a wind speed of 20m/s and a wind angle of
45deg.
Message Comment
$01,WV?*//<cr><lf>
Query the wind velocity
$WIMWV,045,R,020.0,M,A*3D<cr><lf>
FT702LT NMEA response
Example 2
The following example illustrates the NMEA wind velocity data format. The example shows
the FT702LT output in knots with a wind speed of 30.6 knots and a wind angle of 9deg.
Message
Comment
$01,WV?*//<cr><lf>
Query the wind velocity
$WIMWV,009,R,030.6,N,A*31<cr><lf>
FT702LT NMEA response
Description
The WV command returns the wind velocity value in the currently selected format and
units. Polar or NMEA formats are available. Use the DF command, Section 6.4.4, to
select
the required output format and units.
Polar Format: The FT702LT returns the magnitude of the wind speed (m/s) and the wind
direction (0-359 degrees) (see WV Polar, Section 6.4.25).
NMEA 0183 Format: The FT702LT returns the NMEA 0183 Wind Speed and Angle
sentence MWV. The FT702LT returns the wind direction (0-359 degrees) and wind
speed (m/s, knots or km/h) using the MWV Wind Speed and Angle sentence. The
FT702LT Talker ID is always set to WI when NMEA format is selected, irrespective of
any setting that may have been set with the ID command.
End of Manual
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