The HumiStat is a laboratory gas mixer and humidifier. It was designed for low-flow applications in materials science and fuel cell research, combining two-gas dynamic mixing and water vapor addition in a single compact unit. The HumiStat has been discontinued and superceded by 2Mix and 2Wet. All it's capabilities are covered by the Flowseg product family.
What the HumiStat did
The device mixed two input gases at a continuously variable ratio spanning five decades of dynamic range, then optionally added water vapor to the blended stream at a defined partial pressure. Automated step programs allowed humidity and gas composition to change sequentially without operator intervention, which was the main use case for ProboStat measurements stepping through a series of controlled atmospheres. A heated transfer line prevented condensation between the humidifier outlet and the sample.
Specifications
Gas mixing ratio range: 0.00002 to 1 (50,000:1 dynamic range)
Absolute humidity range: 25 to 1,000,000 ppm
Relative humidity: 0.0025 to 100% RH at any temperature
Output flow rate: ml/min to tens of L/min
Pressure: up to 5 bar(a)
Heated transfer line: 1.2 m standard, up to 150°C (1.8 m on request)
Accuracy: ±0.5% absolute
Dimensions: 25 x 27 x 16 cm, 7 kg
Compatible gases: 40+ including H2, He, N2, O2, and others
Fluids: water and compatible low-viscosity liquids
Flowseg equivalents
The Flowseg family separates gas mixing and humidification into two modular instruments that are used together, covering the larger operating range with a modular and expandable architecture.
2Mix handles gas mixing. It covers the same wide dynamic ratio range as the HumiStat mixing section, with support for more than two input gases and a modular design that allows the system to be expanded without replacing existing hardware.
2Wet handles humidification and steam. Evaporation temperature is PID-controlled and fluid volume is tracked by mass, giving direct, repeatable control of pH2O independent of carrier gas flow rate. The same absolute humidity range is covered.
The Flowseg software supports the same programmable atmosphere sequences the HumiStat offered, with additional features including re-dilution from mixed inputs, gas usage logging, automated shutdown timers, and quota management.
For ProboStat users setting up a Flowseg system, see the ProboStat atmosphere control page for a full description of how 2Mix and 2Wet are configured for high-temperature electrochemistry measurements.
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History
NorECs (Norwegian Electro Ceramics AS) developed several instruments for laboratory atmosphere control, primarily for use with the ProboStat sample holder in high-temperature electrochemistry and solid-state materials research.
HumiStat
Combined two-gas mixer and water vapor generator for materials science and fuel cell research. See the HumiStat page for specifications and Flowseg equivalents. Discontinued.
FCMix
A simpler instrument providing humidification and overpressure control for small button fuel cells. The FCMix was a more compact, lower-cost option than the HumiStat, aimed at test setups where a full research-grade gas mixer was not required. Gas mixing and humidification for fuel cell testing is now covered by the Flowseg 2Mix and 2Wet instruments. See the fuel cell page for details on requirements and typical configurations.
Probble
A safety device for fuel cell test setups, providing monitoring and protective functions during testing. Automated shutdown based on configurable conditions is now a built-in feature of the Flowseg software, which stops unattended gas flow on a timer and can be extended with external interlocks.
ProGasMix
Commercial version of the "Oslo mixer" with GasMix software. Discontinued.
For the Flowseg products that replace the NorECs atmosphere control range: see Gas specifications, Fluids and humidification, and Software. For ProboStat-specific atmosphere control setups: see the ProboStat page.
