Campbell Scientific HFP01 Soil Heat Flux Plate User Manual
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Model HFP01 Soil Heat Flux Plate
Example 1. Sample CR3000 Program using Differential Measurement Instructions
'CR3000 Series Datalogger
'Copyright (c) 2007, Campbell Scientific, Inc. All rights reserved.
'This datalogger program measures two HFP01 Hukseflux soil heat flux sensors
'*** Wiring ***
'7H
HFP01 #1 signal (white)
'7L
HFP01 #1 signal reference (green)
'gnd
HFP01 #1 shield (clear)
'8H
HFP01 #2 signal (white)
'8L
HFP01 #2 signal reference (green)
'gnd
HFP01 #2 shield (clear)
'*** Constants ***
Const HFP01_CAL_1 = 14.90 'Unique multiplier for HFP01 #1. 1000/sensitivity (1000/67.1)
Const HFP01_CAL_2 = 14.92 'Unique multiplier for HFP01 #2. 1000/sensitivity (1000/67.0)
'*** Variables ***
'Energy balance sensors.
Public shf(2)
Dim shf_cal(2)
'Soil heat flux plate calibration coefficients.
Units shf = W/m^2
'*** Final Output Data Tables ***
DataTable (soil_hf,TRUE,-1)
DataInterval (0,30,Min,10)
Average (2,shf(1),IEEE4,FALSE)
EndTable
'*** Program ***
BeginProg
'Load the HFP01 factory calibration.
shf_cal(1) = HFP01_CAL_1
shf_cal(2) = HFP01_CAL_2
Scan (1,Sec,3,0)
'Measure the HFP01 soil heat flux plates.
VoltDiff (shf(1),2,mV50C,7,TRUE,200,250,shf_cal(),0)
CallTable soil_hf
NextScan
EndProg
TABLE 6-3. Wiring for Example 2
Description
Color
CR10(X)
Signal
White
SE 5 (3H)
Signal Reference
Green
AG
Shield Clear G
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