HD52.3D…
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V2.2
If the instrument model is not equipped to measure some of the quantities indicated in the
general format, the relevant fields will be empty and multiple consecutive commas will appear
to indicate the missing fields.
The previous string doesn’t include the measurement of solar radiation or amount of rainfall.
Models equipped with a pyranometer or a rain gauge provide to send the measurement with a
second string continuously alternating to the former:
$IIXDR,a,x.x,a,c--c*hh<CR><LF>
The total amount of rainfall is the amount measured from when the instrument is powered.
Note: the Wind Gust measurement is not available in NMEA mode.
E
XAMPLE
Suppose that there are the following environmental conditions:
o
Wind speed = 5.60 m/s (=10.88 knot)
o
Wind direction with respect to magnetic North = 38.7°
o
Barometric pressure = 1014.9 hPa (= 30.0 inHg)
o
Relative humidity = 64.2 %
o
Air temperature = 26.8
°C
o
Solar radiation = 846 W/m
2
Based on the above values, the following can be calculated:
o
Absolute humidity = 16.4 g/m
3
o
Dew Point = 19.5
°C
The strings sent by the instrument in three different cases are indicated below:
Case 1 – instrument measuring only wind speed and direction:
$IIMDA,,I,,B,,C,,C,,,,C,,T,38.7,M,10.88,N,5.60,M*3A<CR><LF>
Case 2 - instrument measuring wind speed and direction, temperature, relative humidity and
barometric pressure:
$IIMDA,30.0,I,1.0149,B,26.8,C,,C,64.2,16.4,19.5,C,,T,38.7,M,10.88,N,5.60,M*36<CR><LF>
Case 3 - instrument measuring wind speed and direction, solar radiation, temperature, rela-
tive humidity and barometric pressure:
$IIMDA,30.0,I,1.0149,B,26.8,C,,C,64.2,16.4,19.5,C,,T,38.7,M,10.88,N,5.60,M*36<CR><LF>
alternated to:
$IIXDR,G,846,,PYRA*29<CR><LF>
For additional information regarding the protocol, visit the site "www.nmea.org".
Type of transducer: G (generic)
Measurement of solar radiation or total amount of rainfall
Measuring unit: empty field
Type of measurement: PYRA (solar radiation) or RAIN (rainfall)
Summary of Contents for Delta OHM HD52.3D Series
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