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For the 4-20mA version of the RadarLEVEL, the sensor reports water level from the bottom, so the datum is
ADDED
. The program supplied uses this method. The 4-20mA RadarLEVEL reports <4mA, confirm that the
distance to the water is set to 7m (the range of the sensor)
7.12
All-In-One Weather Sensors
The Ai1 supports either the Met2 sensor for wind speed and wind
direction measurements in
all
conditions, or the ATMOS 41 for
measurement of meteorological conditions in
freshwater
or
shore
mounted
locations. For higher accuracy applications, the Vaisala
WXT536 is supported for all locations. All these sensors consume less
than 10mA in fast operation and support power saving modes with
average current draw as low as 1mA. While there are many other all-in-
one meteorological sensors available, none are recommended with the
Ai1 due to their higher power requirements which are typically >20mA.
This includes sensors by Gill, Lufft or Global Water. The parameters and
performance of the supported sensors are summarised in the table
below.
Parameter
Met2
Buoy & Pole mount
Fresh or Saltwater
Meter ATMOS 41
Pole mount
Freshwater
Vaisala WXT536
Pole mount
Fresh or Saltwater
Range
Accuracy
Range
Accuracy
Range
Accuracy
Wind Speed
0-40m/s ±0.3m/s, 3%
0-30m/s
±0.3m/s, 3%
0-60m/s
±3%
Wind Direction
0-360°
±3°
0-360°
±5°
0-360°
±3°
Air Temperature
-50 to 60°C
±0.6°C
-50 to 60°C
±0.3°C
Rel. Humidity
0 to 100%
±3%
0 to 100%
±3%
(0-90%)
Precipitation
16
0-200mm/hr
±5%
0-200mm/hr
Better than 5%
Baro. Pressure
500-1100hPa ±1hPa
(-10 to 50°C)
17
600-1100hPa ±0.5hPa
(0 to 30°C)
Solar Radiation
0-1750W/m
2
±5%
Lightning Count
Counts
Variable
Lightning Dist.
0 to 40km
Variable
Tilt
±90°
±1°
Max. Mounting
Pole Diameter
27.2mm OR 30.5 (sleeve
removed)
Mounting Pole
16mm pipe
Integrated U-bolt to suit 31.8 to
50.8mm diameter posts
20NB pipe (26.9mm OD)
When any of these weather sensors is used with the Ai1BUOY, the -POST option must be added to the order. This
provides a side mounting post suitable for mounting meteorological sensors above the top of the buoy and routing
cable to the M12 connector on the base of the Ai1. An internal compass option is also required if wind direction is to
be corrected for buoy movement.
16
Precipitation sensors on the Ai1 do not have a heater and are not suitable for measuring solid precipitation such as snow or ice. Precipitation sensors listed in the table above use sensing techniques suitable for
mounting on moving buoy platforms, although the Met10 may underestimate rainfall on moving platforms with excessive tilt.
17
Resolution is 1hPa on ATMOS 41.
Figure 30
–
Ai1-POLE with integrated weather sensor.
