Campbell Scientific PWS100 Present Weather Sensor - Manual (Page 21)

Section 5. Specifications
5.6.2 Precipitation Measurements
Particle Size*: 0.1 mm to 30 mm (0.004 in to 1.18 in)
Size Accuracy*: ± 5% (for particles >0.3 mm)
Particle Velocity: 0.16 ms -1 to 30 ms -1
Velocity Accuracy*: ± 5% (for particles >0.3 mm)
Types of Precipitation
Detected:
Drizzle, rain, snow grains, snow flakes, hail,
ice pellets, graupel (heavily rimed solid
precipitation), freezing rain, freezing drizzle,
mixed (combination of types above)
Rain Rate Intensity Range: 0 to 400 mm h -1 (M-P Distributed)
Rainfall Resolution: 0.0001 mm
Rain Total Accuracy*: Typically ±10% (accuracy will be degraded for
windy conditions, frozen precipitation, and
very high rainfall rates).
DSD bin sizes: 0.1 mm (diameter) 0.1 ms -1 (velocity)
Data Output: Raw parameter output (particle size, particle
velocity, signal peak value, signal pedestal
value), WMO SYNOP codes (4680, W
a
W
a
-
precipitation and obscurant type), WMO
METAR codes (4678, W
a
W
a
- precipitation
and obscurant type), NWS code, drop size
distribution (DSD) statistics, particle type
distribution, size / velocity intensity maps,
precipitation rate, precipitation accumulation,
visibility range and internal checks
(temperatures, lens contamination, processing
limits).
External Sensors: CS215-PWS supported for temperature / RH
measurement; SDI-12 compatible sensors
supported.
*Accuracy values are for laboratory conditions with reference particles and
visibility standards.
5.6.3 Data Storage and Buffering
The PWS100 has a large internal memory that is split up to store different
types of data. One buffer, the particle buffer, is used to hold raw signal data
captured from the detectors. The size of this buffer and the speed at which it
can be processed is a limit on the maximum rainfall rates the sensor can
measure. For most users, this is not a limitation; if it may be a limitation, please
read the description below.
5-3