Mass Flow Controllers & Meters


Whisper™ MW–Series: Low Pressure Drop Gas Mass Flow Meters

Alicat Whisper™ MW-Series low pressure drop gas mass flow meters are perfect for measuring mass and volumetric flow rates when there is little available system pressure. Low pressure drop minimizes system impact, enabling flow measurement at near-atmospheric pressures.

  • Minimal system impact. Measure gas mass and volumetric flows with pressure drops as low as 0.07 PSID to ensure minimal system impact.
  • High-accuracy. Get real-time measurements with NIST-traceable accuracy to ±0.6% of reading or ±0.1% of full scale for 98+ gases, including custom mixtures defined using Alicat’s COMPOSER™ firmware.
  • Fast, multivariate data. Immediately upon powering up, the meter is ready to display instantaneous flow, gas pressure, and gas temperature readings in your choice of engineering units.
  • Easy integration. Custom process ports and electrical connectors in addition to your choice of EtherNet/IP, EtherCAT, DeviceNet, Profibus, Modbus (RTU and TCP/IP), or serial communications options enables easy integration into your industrial process.

Accessories included with purchase:

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Not exactly what you’re looking for?

  • We offer several additional gas mass flow meter options, including portable, standard pressure drop, high-pressureanti-corrosive, and Coriolis devices (see “models” tab below).
  • If a gas mass flow meter is not what you need, check out our other flow or pressure measurement and control solutions.
  • Still don’t see what you need? Feel free to contact us and discuss custom build options with one of our applications engineers.
Whisper™ MW-Series performance (most products)
  • Available ranges: max 0–1000 SLPM; min 0–0.5 SCCM
  • Flow measurement range: 0.01% – 100% of full scale
  • Standard accuracy calibration, NIST-traceable: ±0.75% of reading or ±0.1% of full scale
  • Optional high-accuracy calibration, NIST-traceable: ±0.6% of reading or ±0.1% of full scale
  • Repeatability: ±(0.1% of reading + 0.02% of full scale)
  • Warm-up time: <1 s
Whisper™ MW-Series operating conditions
  • Compatible gases: 98 pre–loaded selectable gas calibrations; additional mixtures definable with COMPOSER™
  • Operating temperature: –10°C to +60°C
  • Full scale operating pressure: 60 PSIA
  • Full scale pressure drop (range dependent): as low as 0.07 PSID
  • Max differential pressure: 10 PSID
  • Proof pressure: 80 PSIA
  • Reference conditions: user-selectable; defaults: 25°C & 1 ATM (STP) and 0°C & 1 ATM (NTP)
Available device ranges for MW-Series

Alicat offers Whisper meters with custom flow ranges from 0.5 SCCM full scale to 1000 SLPM full scale, each with a measurement range of 0.01% to 100% of full scale. Custom devices are ranged to best meet your specific application needs for full scale flow rate and operating range.

It is important to note that some device specifications vary depending on the full scale flow rate.

If you have any questions or need additional information, reach out to our applications engineers.

Device customization | Build and performance options

  • Communications protocols: analog, RS–232, RS–485, DeviceNet, EtherCAT, EtherNet/IP, Modbus RTU or TCP/IP, PROFIBUS
  • Displays: monochrome or color; integrated or panel–mount
  • Process connections: NPT, SAE, AN, BSPP/G, welded compression, or VCR/VCO fittings
  • Elastomers: Viton, FFKM, EPDM, Silicone
  • Calibration: High-accuracy or custom
  • Performance: Flow totalizer

Accessories | Sold separately

  • Process port fittings and filters
  • Power supplies
  • Communications cables and conversion cables
  • BB3 and BB9 multi-drop breakout boxes
Monitoring and recording bioreactor output

Applications like methane production or hydrogenation benefit from comparing the mass of gas added to the bioreactor with the mass that has been outgassed. When outgassing occurs at atmospheric pressures, the very low pressure drop of Alicat’s Whisper-Series will not induce backpressure while quantifying outgassed mass.

Questions about this product?