06-25-2020 09:43 AM
Hi There,
I am trying to write a VI that will read 8 x 2 wire PT1000 connected to NI9226.
For start, I've only connected the first three channels.
It seems that if I configure the DAQmx create channel AI temperature RTD for two-wire configuration then the DAQmx Read (Analogue DBL 1Chan 1Samp.vi comes up with an error;
Possible reason(s):
Requested value is not a supported value for this property. The property value may be invalid because it conflicts with another property.
Property: AI.ResistanceCfg
Requested Value: 2-Wire
Possible Values: 3-Wire, 4-Wire
Channel Name: Temperatures0
How do I successfully read 8 x analogue channels connected to 8 PT1000 RTD's?
I've attached my VI, please help!!
Regards
Mark
Solved! Go to Solution.
06-25-2020 11:25 PM
I think what you'll have to do is set it up for 3 wire and jumper in the 3rd terminal to one side.
Or set for 4 wire and jumper in both terminals, one to each side.
06-26-2020 01:34 AM
Hi Marken,
in case of such problems you should read the datasheet of the DAQ module! (You probably should do this even before problems arise!)
It clearly states the NI9226 supports only 3-wire and 4-wire Pt1000 sensors.
(Why don't you fake a 3-wire sensor by connecting RTD- and COM?)
06-26-2020 04:25 AM
Hi GerdW,
Thank you very much for your reply.
The suggested solution did the trick that I was looking for.
I can't help myself to mention that reassured I DO read the datasheet of the hardware before order and use. I could say gently that is a different situation that we engineers deal with. The card has been purchased for a different purpose by a different department. I was asked by my manager to see if I can connect some two-wire cheap PT1000 and read the temperature for a quick thermal test.
Again thank you for your time and have a lovely weekend.