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9220 ADC measurement issue

Hi, we have bought an NI9145 with NI9220 (4nos) which is connected to the PXI-8119 as expansion, all the AI’s are configured as scan interface mode in LVRT. We are facing a problem while measuring the voltage, signal connectivity is attached 

 

PS varies from 0-10V. While operating one of the SW1-4 we are not measuring the voltage more than 5.1V in ADC but after 5V the ADC voltage is reducing towards 0V. If all the switches are operated then all the ADC’s are reading up to 10V.

 

Can someone relate to this kind of problem

 

Thanks in advance

 

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Where's your COM reference? You can't just float off into infinity. 

 

See "Floating Differential Connections" in the user manual

http://www.ni.com/pdf/manuals/373920f.pdf

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