USB-6343 Read Incorrect Values

Updated Aug 31, 2018

Reported In

Hardware

  • USB-6343

Software

  • LabVIEW Full

Driver

  • NI-DAQmx

Issue Details

I am taking voltage measurements with a USB-6343. I generating a voltage and putting it into the terminals on the USB device. I have measured the voltage generated with a DMM and it is outputting what I expect it. When I am plugged into some of the terminals and run my code I get the correct value, but when I try the other terminals I get strange values around -5 V.

Solution

Set the DAQmx create channel VI's Input Terminal Configuration to RSE to change the configuration to Reference Single Ended. 

Note: The DAQ device is capable of both Reference Single Ended (RSE) and Differential voltages.

By default it may go to one or the other depending on your DAQ device. So taking data at pin AI 11 in Differential mode is actually being read as the negative input to AI 3 and could provide strange data. 
The image below shows the correct wiring diagram using analog input 3 in RSE mode.

Please see the USB-6343 Screw Terminal Pinout for more information.

WAS THIS ARTICLE HELPFUL?

Not Helpful