USB DAQ Device Loses Communication with LabVIEW, MAX, or Other NI Software

Updated Jun 15, 2019

Reported In

Hardware

  • USB Cable
  • cDAQ-9171
  • cDAQ-9174
  • cDAQ-9178
  • cDAQ-9179

Issue Details

  • My USB DAQ device intermittently loses communication with my machine.
  • I receive an error when creating a DAQmx task saying the USB DAQ device is not present.
  • My LabVIEW application lost communication with the my USB cDAQ

Solution

Follow the suggestions below to resolve the communication issues: 
  • Move the cable and USB cDAQ device away from any electromagnetic interference (EMI) sources
  • Use a USB cable with EMI shielding 
    • Options range from shielded plastic cables, which resist EMI, to IP67-rated metalized plastic cables, which resist EMI and provide potential physical damage from harsh environments
  • Shield the USB DAQ device with a metal case 
    • You can find the electromagnetic certifications and standards for NI devices by searching for device's Product Certification page. 
If there is no communication at all with your device, and you think this might not be related to external electromagnetic interference: 
  • If you are running a LabVIEW application, make sure that the device's name in NI MAX coincides with the one being called in your application. 
  • Try to perform a reset of your device from NI MAX. 
  • Perform a Self-Test on the device in NI MAX and check if it passes the test. 

Additional Information

USB DAQ device communication issues most commonly occur when there is a rapid changing of current at high voltages near the device or cable. This rapid change causes an inductive kick in the voltage source, which causes EMI. 

Standard USB cabling is not intended for use around magnetic fields and are susceptible to EMI.