FLUXUS G809 - The ultrasonic gas flow meter for operation in hazardous areas


Chemical Industry

  • Hazardous Organic and Inorganic Gaseous Media
  • Process Gases
  • Polymerisation Processes
  • Infrastructural Processes

Hydrocarbon Products Handling

  • Hydocarbon Products Flow Measurement
  • Pipeline Integrity Monitoring
  • Allocation Terminals
  • LNG Terminals
  • Underground Gas Storage
  • Gas Distribution and Compressor Stations

Gas Exploration and Processing

  • FWKO and Separator Outlets
  • Scrubbers and Reboilers
  • Gas Treatment
  • Compressor Stations
Technical Datasheet
tsfluxus_g809xx-x1 - en-gb.pdf
Adobe Acrobat Document 1.4 MB


  The FLUXUS G809 is FLEXIM's dual channel ultrasonic clamp-on flow meter for bi-directional flow measurement of gases in hazardous areas ( ATEX, IECEx Zone 1 and FM Class I, Div. 1 / 2 approved).

With its flameproof housing and the corrosion resistant transducers residing inside the rugged VARIOFIX C mounting fixture, ensuring a permanent contact pressure and high mechanical stability, the FLUXUS G809 series is perfectly suited for every demanding industrial application.

The FLUXUS G809 gas flow meter allows for an inherently bi-directional gas flow measurement of operational and standard volume flows. As the transducers are mounted on the outside of the pipe wall, the system does not suffer from wear and tear or clogging, can't be a risk for leaks and will not cause any pressure drops inside the pipe.

Due to its matched and paired transducers as well as the internal temperature compensation (compliant to ANSI/ASME) the measurement system is drift free and zero stable ensuring accurate readings. The gas flow meter can be applied at inner pipe diameters ranging from 6 mm up to 2100 mm (with no limitations on pipe wall thickness or material) and media temperatures from -40°C up to 100°C.

With up to two measurement channels, the FLUXUS G809 permanent gas flow meter can also be applied to difficult measurement points and is completely unaffected by gas density, viscosity and composition as well as temperature and pressure.  Even wet gas up to Liquid Volume Fractions of 5% can be measured.


  • Bi-directional flow measurement of liquids and gases in FM Class I, Div. 1 and ATEX / IECEx Zone 1 areas
  • Very cost effective: No pipe works, No process shut-downs, Virtually maintenance-free
  • Matched, paired and wet calibrated flow transducers (traceable certification to national standards)
  • Excellent zero point stability and drift-free
  • Wide turndown ratio
  • Independent of pipe size, material, operating pressure and gas composition
  • High tolerance to entrained solids and gas wetness
  • Free of wear, tear and abrasion
  • Not prone to clogging or corrosion
  • No pressure loss or source of potential leaks and fugitive emissions


Operating temperature of the transmitter


Degree of protection

IP66 (Transmitter) Coating for Offshore usage

Quantities of measurement

volumetric flow rate, mass flow rate, flow velocity

Optional hazardous area classification

ATEX, IECEx Zone 1, FM Class I, Div. 1 / 2


4 (various combinations of current, binary, frequency Modbus and HART are available)

Communication Protocol

HART, Modbus

Media temperature

-40°C ... +100°C

Pipe diameter range

6 mm ... 2100 mm

Flow velocity range

0,01 ... 35 m/s

Measurement accuracy

±0.5 % of reading ±0.01 m/s, field calibrated ±1 .. 3 % of reading ±0.01 m/s


±0.15% of reading ± 0.01 m/s

Additional Notes

240V or 24V DC power supply version of the transmitter available