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k&z CMP11 & CHP1 wiring connection on CR1000 datalogger

rgupta65 Sep 11, 2011 03:28 AM

Anyone pl, who knows WIRING CONNECTIONS K&Z make pyranomters CMP11 , AND PYREHLIOMETER CHP1 with campbell sci. CR1000 datalogger. pl share.

i m confused with pt100/ thermistor connections on datalogger.
and no manual is given fo the same.

Thanks in advance

rgupta65 Sep 16, 2011 05:56 PM

Hi anyone , Pl rply

Mikey Nov 22, 2011 11:36 PM

I have done some. i need to scare up the wiring. i have it somewhere...if i recall it was just the two wires on the differential channel, but you had to do your own calibration based on the range of the spectrum.

Intermountain Environmental

Spyros Nov 25, 2011 12:25 PM

Below there are same sample programs about these sensors & CR1000.

'CMP11 Measurement

'Cable Function Channel
'------ --------- -------
'Red Signal(+) 1H
'Blue Signal(-) 1L
'Black Ground Gnd

'so mult=1000/sens=1000/4.99=200.4
VoltDiff (CMP11,1,AutoRange,1,True ,0,250,200.4,0)

'Red --> SE7
'Blue -->SE8
'Shield --> G
'Yellow ---> SE9
'Brown ---> SE10
'Green ---> AG
'Grey ---> NC
'10kOhm resistance for (SE9 & Vx2)

'sensitivity=7.85x10(-6)Volts per W/m2
'So mult=1000/sens so mult=127.388

VoltDiff (Pyrh_Irrad,1,mV25,4,False,0,_60Hz,127.388,0)
If Pyrh_Irrad<0 AND Pyrh_Irrad>-50 Then Pyrh_Irrad=0

'Temp_CHP Measurement
BrHalf3W (Rs_Ro,1,mV25,9,Vx2,1,2100,True ,0,_50Hz,100,0)
PRT (Temp_Pyrh,1,Rs_Ro,1.0,0)

I hope this is helpfull

Scientific Enterprises Ltd

DanH Mar 29, 2012 03:50 PM

Dear Spyros,

I will also connect a CHP1 to a CR1000 and found your post here. It helped a little bit but I don't know whihc you mean with the 10kOhm Resistor between SE9 and Vx2.
Because I don't know which voltage you have porgrammed for Vx2.

Best regards

Spyros Apr 17, 2012 09:13 AM


the 10kOhm resistor is used for CHP-1 PT100 measurement for temperature.

From BrHalf3W instruction you can see that i use 2100 mV Excitation.

If you do not need the temperature, do not use it, do not connect yellow & brown cables and do not use 'Temp_CHP Measurement" instructions


DanH Apr 25, 2012 07:54 AM

Thank you a lot.
It works all fine, I had used the wrong SE Channel in the instruction.

Best regards

XxVashxX Aug 21, 2015 06:16 PM

Hello i recently connect a CHP1 to a CR1000 using the reference of mails comments above and i note that the temperature of the CHP1 is always lower than the ambient temperature and datlogger temperature (in example if ambient temperature is 14 degrees celsius CHP1 temperature is 7 degres, if ambient temperature is -2 degress celcius the temperature in the chp1 -6........ and so....
I use a 10 kohm resistance, is not a precision resistance but have low temp coeficient...

The graphics of ambient temperature and CHP1 temperature have the same form and looks coherent but the CHP1 temperature is always below the ambient temperature.

My question is is normal to have lower temperature readings in the CHP1??

Thank you
Best Regards

aps Aug 24, 2015 08:51 AM

The answer is no, not by 7 C. The two likely issues are:

a) the 10k resistor you are using is not good enough. Every 1% error in that resistor will equate to about a 3 deg C error in temperature.

b) that your wiring is breaking the assumptions of 3-wire measurements (which tries to compensate for errors caused by the connecting wires). One common error is connect the Grey and Green wires together (for this sensor)which halves the resistance in one wire. The Grey wire should not be connected at all. There are other possible wiring errors that could cause this.

XxVashxX Aug 24, 2015 12:57 PM


Thank you i will cheq for the cable connections, i think the grey cable is connected.

Best Regards

Garoum Nov 21, 2023 12:56 AM

This post is under review.

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