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GFM-3XXXUC USB Gas Flow Meter

LexcomSys™ GFM-3XXXUC Programmable Gas / Air Flow Meter and Flowswitch Controller


lexcom GFM

The LexcomSys™ GFM-3XXXUC is a versatile, highly configurable, high performance USB flow meter specifically designed to suit a wide range of applications in mind including testing, production, research, medical, and scientific. Its unparalleled performance, with a particular reference to very high sampling rates supported with excellent sensitivity, makes it an excellent choice for applications concerning reconstruction of high frequency flow change characteristics in gas propagation.

Examples include air pump / fan performance analysis, failure prediction, flow path optimisation, turbulence reduction, and other, more conventional flow measurement applications where high sampling rates can lead to a massive increase in effective accuracy of readings over a set period.


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  • programmable airflow meter, switch, totaliser
  • self-calibrating: AIR / O2 / N2 / controlled mix
  • temperature-compensated readings
  • outstanding sensitivity & repeatability
  • accurate, high resolution measurements
  • very fast sampling response
  • high sampling rates up to 2kHz
  • detachable / replaceable sensor design
  • permanent, autoclavable & disposable sensors
  • small dead space (sensor choice): down to 1ml
  • 1 device, 4 different sensors supported
  • directly human-readable ASCII data output


  • multiple modes incl. for dosing & totaliser
  • highly configurable with extensive options
  • easy-to-use and flexible command structure
  • configurable, pre-programmable, and robust
  • retains & loads last saved config at bootup
  • full current config can be queried explicitly
  • readable, compliant, and consistent commands


  • autonomous operation capability
  • simultaneous electronic & digital interfaces
  • programmable flow switch
  • limit hysteresis setup in both flow directions
  • 2 additional USB control solid state relays
  • separate, independent, standard RS-232 link
  • RS-232 fully functional in autonomous use


  • sampling rates 5Hz to 2kHz
  • output rates from 1/day to 2kHz
  • high resolution 14 bit sampling
  • sensitivity to reliably detect a few ml/min
  • flow ranges up to +-250 slm (std l/m)


  • standard USB 2.0 interface (data & power)
  • platform-native USB COM port implementation
  • Windows / MacOS / Linux: no 3rd party driver req’d *
* For legacy support, a simple low profile INF driver is also supplied, for Windows 7 only (other supported operating systems require no driver files at all).