Visibility Measurement Specifications; Weather Sensing Specifications; Table 23 Optical Specifications Of The Light Receiver; Table 24 Visibility Measurement Specifications - Vaisala PWD22 User Manual

Chapter 8______________________________________________________________Technical Data
VAISALA _______________________________________________________________________ 109
Table 23 Optical Specifications of the Light Receiver
Property
Detector
Optical filter/window
Backscatter light
source
Visibility Measurement
Specifications
Table 24

Visibility Measurement Specifications

Property
Measurement range of
1)
MOR
Accuracy
Instrument consistency
Time constant
Update interval
1) Meteorological Optical Range

Weather Sensing Specifications

Table 25 Weather Sensing Specifications
Property
Precipitation detection
sensitivity
Weather type identification
Weather type reporting
Precipitation intensity
measurement
Description / Value
Photodiode
RG780 glass
Near-infrared LED for contamination and blockage
measurement
Description / Value
10 ... 20000 m
+/-10%, range 10 ... 10000 m
+/-15%, range 10km ... 20 km
+ 5%
60 seconds
15 seconds
Description / Value
0.05 mm/h or less, within 10 minutes
7 different types of precipitation (rain,
freezing rain, drizzle, freezing drizzle, mixed
rain/snow, snow, ice pellets)
Precipitation (unknown type)
Fog (mist), haze (smoke, sand) or clear
WMO code table 4680
Code letters for precipitation, NWS (National
Weather Service, USA)
Range 0.00 ... 999 mm/h