SETARAM Flexi WET200 Humidity Generator

Overview

The SETARAM Flexi WET200 is a precision humidity generator engineered for controlled, traceable, and dynamically programmable humidification of carrier gases in thermal analysis and materials characterization laboratories. It operates on the fundamental principle of mixing dry and saturated gas streams via mass flow-controlled blending—ensuring thermodynamic consistency and metrological reliability across its full operating range. Unlike static saturation or permeation-based systems, the Flexi WET200 employs active closed-loop regulation of relative humidity (RH), temperature, and volumetric flow using integrated sensors and Eurotherm PID controllers. This architecture enables stable, reproducible humidity delivery under isothermal or dynamic ramp conditions—critical for studying moisture-dependent phase transitions, sorption kinetics, and long-term stability behavior in solid-state materials.

Key Features

• Active dual-stream mixing system with independent mass flow controllers for dry and saturated gas inputs
• Closed-loop humidity control with real-time feedback from calibrated capacitive RH sensor and Pt100 temperature probe
• Programmable humidity profiles—including step, ramp, hold, and cyclic sequences—via intuitive touchscreen interface
• Thermally stabilized mixing chamber with precise temperature control (ambient to 70 °C) and optional heated transfer line (up to 85 °C) to prevent condensation
• Gas compatibility with inert (He, Ar, N₂), reactive (CO₂), and ambient air—enabling studies under chemically relevant atmospheres
• Compact benchtop design (W × D × H: 320 × 360 × 220 mm) with modular gas inlet/outlet ports for seamless integration into existing instrument setups
• No consumables or membranes required; maintenance-free operation with validated calibration traceability to NIST-traceable standards

Sample Compatibility & Compliance

The Flexi WET200 is designed for direct coupling with thermal analysis platforms—including SETARAM SENSYS EVO TG-DSC, RX calorimeters, and third-party instruments such as PerkinElmer STA, Netzsch STA 449, and TA Instruments Q5000 IR. Its output stream meets ISO 8503-2 and ASTM E104–22 requirements for controlled humidity exposure during gravimetric and calorimetric measurements. When used in pharmaceutical development workflows, the system supports ICH Q1A–Q5C stability testing guidelines and aligns with USP and on moisture interaction assessment. For GLP/GMP environments, audit trail functionality (via optional Ethernet logging) ensures compliance with FDA 21 CFR Part 11 for electronic records and signatures.

Software & Data Management

The Flexi WET200 is operated via an embedded Linux-based HMI with a 7-inch resistive touchscreen. All humidity and temperature setpoints, ramp rates, dwell times, and flow parameters are stored in non-volatile memory and exportable as CSV files. The controller supports RS232 and Ethernet interfaces for remote monitoring and synchronization with host instrument software (e.g., SETARAM CALISTO, NETZSCH Proteus®). Real-time data logging at 1 Hz resolution includes RH (%), temperature (°C), total flow (mL/min), and individual MFC valve positions. Optional OPC UA server integration enables interoperability with laboratory information management systems (LIMS) and SCADA platforms for centralized environmental condition tracking.

Applications

• Pharmaceutical Sciences: Quantifying hygroscopicity of amorphous APIs, mapping deliquescence points, assessing crystallization onset under variable RH, and validating packaging barrier performance
• Polymers & Composites: Measuring moisture diffusion coefficients, evaluating plasticization effects on T_g, and characterizing hydrolytic degradation kinetics in polyesters and polyamides
• Energy Materials: Investigating water uptake in MOFs and zeolites for thermal energy storage, probing proton conductivity in PEM fuel cell membranes, and assessing hydration/dehydration cycling stability
• Construction Materials: Monitoring capillary absorption in cementitious systems, correlating RH-induced microcracking with compressive strength loss, and simulating long-term exposure in accelerated aging chambers
• Metallurgy & Corrosion Science: Conducting in-situ TGA-MS studies of oxide layer formation on aluminum alloys and steels under controlled humidity, and quantifying hydrogen embrittlement thresholds
• Food Science: Mapping glass transition shifts in carbohydrate matrices, evaluating caking propensity in powdered dairy products, and modeling shelf-life under ambient storage conditions

FAQ

What gases can be used with the Flexi WET200?
The system is validated for use with helium, nitrogen, argon, carbon dioxide, synthetic air, and ambient air. Gas-specific calibration offsets are preloaded in firmware to ensure accurate RH calculation across molecular weight and thermal conductivity variations.

Can the Flexi WET200 be used with non-SETARAM instruments?
Yes—it features standard 6 mm Swagelok inlet/outlet fittings and delivers a stable, conditioned gas stream compatible with any analytical instrument requiring humidified purge gas, including FTIR cells, Raman sample chambers, and environmental SEM stages.

Is external cooling required for operation?
No. The system operates without external chillers or refrigerated traps. Condensation is prevented by maintaining the entire gas path—including the transfer line—at temperatures above dew point via active heating and thermal insulation.

How is humidity accuracy verified?
Each unit undergoes factory calibration against a chilled-mirror dew point hygrometer (Michell Optidew) traceable to NPL standards. Users may perform periodic verification using a portable reference hygrometer (e.g., Rotronic HC2-AW) inserted downstream of the outlet.

Does the Flexi WET200 support automated method sequencing with thermal analyzers?
Yes—via digital I/O triggers and serial command protocol, it synchronizes humidity ramps with temperature programs in TG-DSC runs, enabling fully autonomous multi-condition experiments without manual intervention.