Sutron 8310 - Page 69

Sutron Corporation 8310 & 7310 Users Manual 8800-1125Rev. 2.7 (BETA) 4/16/2014 pg. 69
Hours sunshine accumulation: sample input every 10 seconds, accumulate time when
input > threshold, log every 2 minutes, reset every day. This requires 2 measurements,
one to do the accumulation with 24 hour reset and the other to log it every 2 minutes.
Measurement 1: Sample pyranometer every 10 seconds accumulate for 24 hours, with
reset at midnight:
Name: Sunshine
MeasType: accumulate
Sample Interval: 00:00:10
Interval: 24:00:00
Time: 00:00:00
Threshold: 120 watts/meter^2
WeightForTime = YES
AccumulateEvent = YES
Input Type/Slope/Offset: as needed to sample the input and convert it to
watts/meter^2
M1.O1 minutes sunshine (use processing:linear with slope of 0.016667 if you want the
value in hours sunshine (hrs = min*1/60))
Display=YES
Log=NO
Measurement 2: Sample M1.O1 every 2 min and log/transmit it
MeasType: instantaneous
Input type: Reference (M1.O1)
Time: 00:00:00
Interval: 00:02:00
M2.O1
Log=YES
DewPoint
Takes a sample of air temperature and relative humidity, computes dew point and has outputs
of air temperature, relative humidity and dewpoint. The calculation is done according to "WMO
Guide to Meteorological Instruments and Methods of Observation" WMO-No.8 seventh edition,
2006. The equation is:
a = (ln(r/100)/17.62) + (t/(t + 243.12))
DewPoint = a * 243.12/(1-a)
Where r is percent RH (0-100), t is air temperature in C, and ln is log base e or natural logarithm.
The calculated DewPoint is in C as well.
This measurement has the following properties: