Our full technical support staff does not monitor this forum. If you need assistance from a member of our staff, please submit your question from the Ask a Question page.


Log in or register to post/reply in the forum.

Cr1000x and CNR4


HMNIBIO Apr 16, 2020 09:34 AM

Hello,

I have been asked to add a CNR4 to a CR1000x. The radiometer must have been bought from K&Z directly, evident from the cable colours.

Measuring temperature should be straight forward when using a 4WPB100 module, but I get non-sensical readings. I tried both thermistor and Pt100. This was my program & wiring for the (preferential) Pt100:

'Diff 1-4 for radiation measurements

'5H, 5L, G - 4WPB100

'4WPB100 G - yellow

'4WPB100 L - grey

'4WPB100 H - jumper wire to VX3

'6H - green

'6L - brown

'G - shield

Public cnr4_T_C

Public cnr4_T_K

BrHalf4W(cnr4_T_C,1,mV1000,mV1000,5,VX3,1,4000,True,True,0,50,1,0)

PRT(cnr4_T_C,1,cnr4_T_C,1,0)
cnr4_T_K=cnr4_T_C+273.15

Thermistor:

'4WPB100 G - black

'4WPB100 L - white

'4WPB100 H - jumper wire to VX3

BrHalf(cnr4_T_C,1,mV5000,9,VX1,1,2500,True,0,50,1,0)

cnr4_T_C=1000*(cnr4_T_C/(1-cnr4_T_C))
CNR4TC=1/(1.0295e-3+2.391e-4*LN(cnr4_T_C)+1.568e-7*(LN(cnr4_T_C))^3)-273.15

This would be easier if the radiometer had been provided by Campbell. But should the measurement not be absolutely possible with the K&Z-wiring, too?

For the record, measurements were fine on a Volt116, using CDM_resistance.

Cheers,

H

Log in or register to post/reply in the forum.