AMETEK Model 5900 Trace Moisture Analyzer

Overview

The AMETEK Model 5900 Trace Moisture Analyzer is a high-sensitivity, tunable diode laser absorption spectroscopy (TDLAS)-based instrument engineered for continuous, real-time quantification of water vapor at sub-part-per-trillion (pptv) to low-parts-per-billion (ppbv) levels in industrial process gas streams. Designed for demanding applications in semiconductor manufacturing, high-purity gas production, specialty chemical synthesis, and cryogenic air separation, the Model 5900 operates on the fundamental principle of near-infrared laser absorption at a precisely selected water-specific rotational-vibrational transition (typically ~1368 nm or ~1877 nm, depending on configuration). Its optical path utilizes a multipass Herriott cell to achieve effective path lengths exceeding 100 meters, enabling exceptional detection sensitivity and long-term stability without consumables or reagents. Unlike electrochemical or chilled-mirror hygrometers, the Model 5900 delivers absolute, calibration-stable measurements traceable to NIST standards—critical for process validation and regulatory compliance in controlled environments.

Key Features

• Ultra-low detection limit: <1 ppbv H₂O (typical, dependent on sample matrix and pressure)
• Full-scale measurement range: 0–10 ppbv to 0–1000 ppmv (field-selectable via software)
• Response time (T90): <10 seconds for step changes in moisture concentration
• Integrated temperature- and pressure-compensated measurement engine ensuring accuracy across variable process conditions
• Robust, stainless-steel wetted materials (316L SS, electropolished) compatible with aggressive gases including Cl₂, HCl, NH₃, HF, and ultra-high-purity N₂/Ar/He
• Modular design supporting both extractive sampling (with heated sample line and filter options) and in-situ probe configurations
• Self-diagnostic optics monitoring with real-time signal-to-noise ratio (SNR) reporting and automatic baseline correction

Sample Compatibility & Compliance

The Model 5900 is validated for use with non-corrosive and mildly corrosive process gases at pressures from vacuum to 10 bar(g) and temperatures up to 180 °C (with optional high-temp probe). It meets stringent purity requirements for ISO 8573-1 Class 1 compressed air and ASTM D7443 for trace moisture in liquefied petroleum gas (LPG). The analyzer complies with electromagnetic compatibility per IEC 61326-1 and safety standards per UL 61010-1. Its architecture supports integration into GMP/GLP-regulated facilities: audit trail logging, user access levels (admin/operator), electronic signature capability, and full 21 CFR Part 11 compliance when deployed with AMETEK’s certified firmware and secure network configuration.

Software & Data Management

Operation is managed through AMETEK’s proprietary Insight™ software suite, accessible via embedded web interface or remote desktop connection. Insight™ provides real-time trend visualization, configurable alarm thresholds (high/low, rate-of-change), automated calibration event scheduling, and raw spectral data export in CSV or HDF5 format. All measurement data—including timestamps, diagnostic flags, pressure/temperature compensation values, and laser wavelength drift logs—are stored locally on a redundant SD card and optionally streamed via Modbus TCP, Profibus DP, or 4–20 mA analog output. Historical datasets support retrospective analysis for root-cause investigation and process capability studies (Cp/Cpk).

Applications

• Monitoring moisture breakthrough in molecular sieve dryers and desiccant beds for bulk gas delivery systems
• In-line verification of moisture content in etch and deposition precursor gases (e.g., SiH₄, WF₆, NH₃) in semiconductor fab tools
• Quality assurance of ultra-high-purity carrier gases used in GC-MS and ICP-MS laboratories
• Leak detection and integrity verification of vacuum chambers and gloveboxes (via residual H₂O mapping)
• Control feedback for regenerative dryer cycling in pharmaceutical nitrogen generation skids
• Compliance testing for ISO 8573-8 purity class certification in medical air and surgical gas distribution networks

FAQ

What is the recommended calibration frequency for the Model 5900?
Calibration verification using NIST-traceable zero gas (dry nitrogen) and span gas (certified ppbv-level moisture standard) is recommended every 30 days for critical GMP applications; quarterly verification suffices for less stringent process control environments.
Can the Model 5900 measure moisture in hydrogen or oxygen service?
Yes—provided appropriate material compatibility verification is performed and optional catalytic converter accessories are installed to mitigate interference from background H₂O formation in reactive gas matrices.
Is field service and spare parts support available globally?
AMETEK maintains certified service centers in North America, Europe, and Asia-Pacific, with 48-hour response SLAs for critical spares under extended warranty contracts.
Does the analyzer require periodic consumables or reagents?
No—the TDLAS optical measurement principle is inherently reagent-free and consumable-free, eliminating ongoing operational costs associated with sensor replacement or electrolyte refills.