Noise When Using the PXIe-4300 with TB-4300B to Measure Voltage Input

Updated Apr 26, 2023

Reported In

Hardware

  • PXIe-4300
  • TB-4300B
  • TB-4300

Issue Details

I want to measure high voltage (30-300 V signal inputs), using PXIe-4300 with TB-4300B. I have used an oscilloscope to ensure the signal I am measuring is clean, however the input of the 4300 is showing noise above the above the absolute accuracy specification. How do I reduce this noise to within specification?

Solution

  1. You can wire the COM pin directly to the analog input negative pin in TB-4300B, in order to make the measurements more accurate.
  1. Ensure that your device is within the calibration interval. If the temperature has significantly changed since the last calibration you will want to do a self calibration in NI MAX.   
  2. Lastly, you can improve the accuracy by enabling the 10kHz or 100kHz low pass filter on the 4300 in software. This can be done in LabVIEW through a DAQmx Property Node set to Analog Input -> General Properties -> Filter -> Analog Filter -> Lowpass -> Enable to true.
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