Campbell Scientific PWS100 Present Weather Sensor - Manual (Page 75)

Section 7. Operation
Higher codes indicate other type of data (stored every 10 seconds) where
values a, b, and c have different meanings as indicated below:
1000 Time stamp (in seconds from 1/1/2007)
1001 Temperature, RH and wetbulb temperature
1002 Visibility data (upper, lower and calibrated mV sample)
1010 Wetness grid value
1011 Error codes (temperature / RH error code, wetness error code)
1012 Aux sensor value
Extra information about each particle can be given from the sensor if the
sensor is set up to store such extra information. The command to enable the
storage of this extra information is:
FUZZYDIAG 1 ↵
Once this command is given then the following information will also be stored
for each particle observed:
1013 Minimum signal peak, pedestal height and signal to pedestal ratio for
detector 1
1014 Minimum signal peak, pedestal height and signal to pedestal ratio for
detector 2
1015 Polycrystalline flag (1 for polycrystalline, 0 for not polycrystalline)
To disable the storage of the above extra information (which if not required
frees up more memory to store more history of particles) use the command:
FUZZYDIAG 0 ↵
This data is part of the logical processing of each particle as the signal to
pedestal ratio value is used in one of the fuzzy logic tables to help determine
particle type. It has been shown from studies of the PWS100 signal output that
snow grains and snowflakes exhibit much smaller ratios than for drizzle and
rain. This is only possible due to the structured nature of the detection volume
and the fact that polycrystalline particles such as snow exhibit refraction and
reflection of light from multiple scattering sites as opposed to mainly refraction
from what is effectively one scattering site for liquid particles.
In terms of data storage with FUZZYDIAG enabled 5 records are used every
10 seconds (1001, 1002, 1010, 1011 and 1012) plus 4 records for every
processed particle that passes through the volume (0-99, 1013, 1014 and 1015).
For example if 20 particles per second are processed then 80.5 records are used
per second. Since 1000000 records can be stored in the LPA only 1242 seconds
worth of data can be stored as opposed to 4878 seconds with FUZZYDIAG
disabled. FUZZYDIAG will be disabled by default.
Three values are always given in the HDATA output; however,
if the particular coded output has less than three parameters the
remaining values will be zero, 1010 and 1012 are examples of
this. NOTE
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