MNK MS900 Portable Trace Moisture Analyzer

Overview

The MNK MS900 Portable Trace Moisture Analyzer is a field-deployable, chilled mirror-based hygrometer engineered for high-reliability quantitative measurement of water vapor concentration in non-corrosive industrial gases. It delivers simultaneous, real-time readouts of dew point temperature (°C) and volumetric moisture content (ppm_v)—critical parameters for process integrity, equipment protection, and regulatory compliance across gas-critical infrastructure. Its core sensing architecture employs a high-stability imported chilled mirror sensor, operating on the thermodynamic principle of condensation point detection: a precisely temperature-controlled mirror surface is cooled until dew forms, with optical detection of condensate onset enabling direct, primary-standard traceable dew point determination. This method eliminates drift associated with polymer or aluminum oxide sensors and ensures long-term metrological stability without zero/span gas dependency. The MS900 is explicitly validated for use with compressed air, nitrogen, argon, hydrogen, SF₆, natural gas (non-sour), and other inert or mildly reactive gases—excluding CO₂ due to its condensation behavior under sub-zero conditions.

Key Features

• Integrated rechargeable 24 V Li-ion battery supporting continuous operation for >8 hours—enabling full-shift field diagnostics without external power.
• Dual-parameter display: simultaneous dew point (°C) and moisture content (ppm_v) on a high-contrast backlit LCD, with configurable units and decimal resolution.
• Extended operational range: calibrated dew point measurement from –80 °C to –10 °C; non-calibrated extrapolation down to –100 °C and up to +20 °C for trend monitoring and alarm verification.
• Rapid thermal response: t₉₀ ≤10 seconds within the –80 °C to –10 °C range at standard conditions (20 °C, 0.1 MPa), enabling dynamic process evaluation during purging or drying cycles.
• Robust mechanical design: 1/8″ stainless steel internal flow path and Swagelok-compatible fittings ensure compatibility with high-purity gas systems and resistance to particulate-induced clogging.
• Low-maintenance architecture: no consumables, no electrolyte, and a recommended calibration interval of 24 months—minimizing total cost of ownership and downtime.

Sample Compatibility & Compliance

The MS900 is qualified for sampling non-corrosive, particle-free gases including instrument air, feedstock nitrogen, synthesis gas (H₂/N₂ blends), SF₆ insulation gas, transformer breathing air, and cryogenic plant purge streams. It is not intended for CO₂, chlorine, ammonia, or acidic gas matrices. Its measurement methodology and performance specifications align with internationally recognized standards for moisture-in-gas testing: ISO 8573-3 (compressed air purity classes), ASTM D2013 (moisture in gaseous fuels), and IEC 60076-15 (moisture limits in power transformer insulating gases). While the analyzer itself does not provide electronic audit trails, its stable analog output and manual calibration log support GLP-compliant recordkeeping when integrated into documented QA workflows.

Software & Data Management

The MS900 operates as a standalone instrument with embedded firmware—no PC software required for basic operation. All measurements are stored internally with timestamp, dew point, ppm_v, ambient temperature, and pressure (if optional sensor installed). Up to 10,000 data points can be recalled and reviewed directly on-device using intuitive navigation keys. Data export is supported via USB-C interface to CSV files compatible with Excel, LIMS, or SCADA historian systems. Firmware updates and configuration adjustments (e.g., flow rate compensation, unit selection, alarm thresholds) are performed through a secure command-line interface accessible via terminal emulator—ensuring reproducibility and traceability in regulated environments.

Applications

• Petrochemical refining: Monitoring moisture in fuel gas streams and catalyst purge air to prevent corrosion and bed deactivation.
• Electrical utilities: Verifying SF₆ moisture levels in circuit breakers and GIS compartments per IEEE C37.122 and IEC 62271 requirements.
• Industrial gas production: Certifying dryness of nitrogen blankets, argon shielding gas, and oxygen plant product streams against ISO 8573-1 Class 2–4 specifications.
• Pharmaceutical manufacturing: Qualifying compressed air used in sterile processing (Grade A/B/C/D) per ISO 8573-1 and EU GMP Annex 1.
• Aerospace & defense: Validating dryness of pneumatic control air and avionics purge gas prior to system pressurization.

FAQ

What gases are incompatible with the MS900?
CO₂, HCl, Cl₂, NH₃, SO₂, and other corrosive or condensable gases at low temperatures may damage the chilled mirror surface or cause erroneous readings.
Does the MS900 require zero or span gas for routine operation?
No. As a primary-standard chilled mirror instrument, it requires no calibration gases—only periodic verification against a NIST-traceable reference dew point generator every 24 months.
Can the MS900 measure liquid-phase water or aerosols?
No. It is designed exclusively for gaseous phase moisture analysis. Liquid carryover or mist must be removed upstream using coalescing filters and knock-out pots.
Is pressure compensation automatic?
The base model provides dew point at sample pressure; optional integrated pressure transducer enables real-time ppm_v calculation per the Magnus-Tetens equation, with user-selectable reference pressure (e.g., 101.325 kPa).
What is the minimum detectable dew point?
The instrument achieves reliable condensate detection down to –100 °C under controlled lab conditions; field accuracy below –80 °C is advisory and intended for trending—not specification compliance.