Bad measurements on the NI-USB 6210

[Wavicle]

Hi,

I was reading temperatures with the VI attached below and it was working but suddenly the measurements started to fluctuate very hard, going from 20 degrees to -8 to 0 and sometimes back to 20. What could be happening?

Thanks

[ZYOng]

The issue could be coming from the temperature sensor or the environment. Have you tried connecting your sensor to a scope or multimeter?

[santo_13]

Need more detail on external wiring, components etc., to guess what could be wrong. It is rarely a case of a faulty DAQ. One way to rule out an issue with DAQ, connect the Analog Input to GND, run your program, now you should not see any spikes, the measurement should be around 0V with noise. If you cannot reproduce the sudden fluctuation when the analog input is connected to GND, the issue is external to your DAQ and program.

[Wavicle]

Hi

The image that I attached is what I get from measuring a constant DC voltage of 5.41. 

Santhosh, I have to connect the AI- to the AIGND, right? And to the AI+?

Thanks

 

[santo_13]

connect both AI+ and AI- to AIGND

[Wavicle]

I did it and I get a value of -0.009 volts so I guess that the analog inputs are working