Campbell CVF4 Manual de Instruções descarregar pdf (Página 25)

CMP6-L, CMP10-L, CMP11-L, and CMP21-L Pyranometers

In CRBasic, the conversion to resistance is entered as a mathematical

expression. In Edlog, Instruction P59 (Bridge Transform) does the conversion.

The Steinhart-Hart equation is used to convert resistance to temperature. The

Steinhart-Hart equation for converting resistance to degree Celsius is as

follows:

Temperature = 1/[A + B*LN(resistance) + C*(LN(resistance))^3] - 273.15

Where A, B, and C are coefficients for the Steinhart-Hart equation.

The coefficients for the Steinhart-Hart equation are specific to the thermistor

contained in your CMP21. A calibration certificate that lists these coefficients

is shipped with each CMP21 pyranometer.

In CRBasic, the Steinhart-Hart equation is entered as a mathematical

expression. Edlog dataloggers can use Instruction P200 (requires a newer

datalogger operating system).

7.3.3 Example Programs

7.3.3.1 CR1000 Example Program for Measuring a CMP6

Although this example is for the CR1000, other CRBasic dataloggers are

programmed similarly. The following program measures the CMP6 every

second and converts the millivolt output to W•m

–2

. A sensor calibration of

14.33 μV / W•m

–2

is used for the example program. Every 10 minutes, the

program outputs the average and standard deviation of the flux (W•m

–2

)

measurements. Wiring for this example is given in TABLE 7-6able 7-6.

TABLE 7-6. CR1000 Wiring for CMP6 Example Program

Wire Color

Description

CR1000

Jumper*

White

Solar Signal (+)

Black

Solar

Signal (–)

Clear

Shield

* Jumper 1L to

with user-supplied 26 AWG or larger wire.

'CR1000 Series Datalogger

Public PTemp

Public Batt_Volt

Public CMP6_Irr

Units CMP6_Irr = W/m2

DataTable (TenMin,1,-1)

DataInterval (0,1,Min,4)

Minimum (1,Batt_Volt,FP2,0,False)

Sample (1,PTemp,FP2)

Average (1,CMP6_Irr,FP2,False)

StdDev (1,CMP6_Irr,FP2,False)

EndTable

BeginProg

Scan (1,Sec,0,0)

1 2 ... 20 21 22 23 24 25 26 27 28 29 30 ... 41 42

Comentários a estes Manuais

Sem comentários

Campbell CVF4 Manual de Instruções Página 25

Comentários a estes Manuais

Manuais e produtos relacionados com não Campbell CVF4