Campbell Scientific LI200X-L LI-COR Silicon Pyranometer - Manual (Page 10)

LI200X Pyranometer
TABLE 4-1. Multipliers Required for
Average Flux and Total Flux Density in Sl
and English Units
UNITS MULTIPLIER PROCESS
W m -2 200 Average
MJ m -2 t * 0.0002 Total
kJ m -2 t * 0.2 Total
cal cm -2 min -1 0.2 * (1.434) Average
cal cm -2 t * 0.2 * (0.0239) Total
t = datalogger execution interval in seconds
4.1 Example Programs
The following programs measure the LI200X every 10 seconds, and convert
the mV output to Wm
-2 and MJm -2 . Both programs output an hourly average
flux (Wm -2 ) and a daily total flux density (MJm -2 ). Negative values are set to
zero before being processed. Wiring for the examples is given in Table 4-2.
TABLE 4-2. Wiring for Example Programs
Color Description CR1000 CR10X
Red Signal 1H 1H
Black Signal Reference 1L 1L
White Signal Ground AG
Clear Shield G
4.1.1 CR1000 Example Program
In the CR1000 example, a daily total flux density is found. This total flux
density is in MJ m
-2 day -1 . Negative values are set to zero before they are
added to the running total.
'CR1000
'Declare Variables and Units
Public SlrW
Public SlrMJ
Units SlrW=W/m²
Units SlrMJ=MJ/m²
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