Campbell Scientific 43347 RTD Temperature Probe and 43502 Aspirated Radiation Shield User Manual

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43347 RTD Temperature Probe, 43502 and 41003-5 Radiation Shields

'CR3000

'Declare Variables and Units
Public RTD_Res
Public RTD_Cal_C

Public 43502_Tach
Units 43502_Tach = Hz

'Define Data Tables
DataTable(PRT_Data,1,1000)
DataInterval(0,15,Min,1)

Average (1,RTD_Cal_C,IEEE4,False)
Sample (1,43502_Tach,FP2)

Endtable

'Main Program

BeginProg
Scan(1,Sec,10,0)

'Measure the 43347-IX probe
Resistance (RTD_Res,1,mV200,1,Ix1,1,170,True,True,0,_60Hz,1,0)

'Convert RTD resistance to temperature
'43347 calibration T=-250.052585+(R*2.375187e-1)+(R^2*1.258482e-5)
RTD_Cal_C = -250.052585+(RTD_Res*2.375187e- 1)+((RTD_Res^2)* 1.258482e-5)

'Measure the 43502 tachometer output

PulseCount (Tach_Hz,1,11,0,1,1.0,0)

CallTable PRT_Data

Next Scan
EndProg

6.2.2 Datalogger Programming for Uncalibrated 43347-IX Probes

The measurement result of the Resistance instruction with a multiplier of 1.0
and an offset of 0.0 is the RTD resistance in ohms. For uncalibrated probes,
the PRT instruction is used to convert the ratio Rs/Ro to temperature in
accordance with DIN Standard 43760, where Rs is the measured resistance of
the RTD, and Ro is the resistance of the RTD at 0 degrees C (1000 ohms).
Because the alpha of the 43347 is 0.00375 and the alpha of DIN standard is
0.00385, a multiplier of 1.0267 (0.00385/0.00375) is required in the PRT
instruction.

The PRT Instruction with its parameters is listed below:

PRT( Dest, Reps, Source, Mult, Offset )

The following example program measures an uncalibrated 43347-IX probe
every 1 second and stores a 15 minute average temperature in degrees Celsius.

'CR3000

'Declare Variables and Units
Public RTD_Res
Public RTD_RsRo

Public RTD_C
Public 43502_Tach
Units 43502_Tach = Hz