MNK MPS950 Online Dew Point Analyzer
| Brand | MNK |
|---|---|
| Origin | Beijing, China |
| Model | MPS950 |
| Product Type | Online Dew Point Analyzer |
| Operating Temperature Range | –100 to 0 °C |
| Accuracy | ±2 °C |
| Repeatability | ≤ ±1 °C |
| Sample Flow Rate | 2–3 L/min (recommended: 2 L/min) |
| Response Time (90%) | 15 min at –10 to –80 °C |
| Pressure Range | 0–1 MPa |
| Ambient Operating Conditions | 5–45 °C, 0–90% RH |
| Output Signal | 4–20 mA |
| Power Supply | 220 VAC ±10%, 50 Hz ±5% |
| Dimensions | 270 × 132 × 330 mm |
| Weight | ~3 kg |
Overview
The MNK MPS950 Online Dew Point Analyzer is a high-stability, industrial-grade hygrometric instrument engineered for continuous, real-time monitoring of trace moisture in non-corrosive process gases. It operates on the principle of capacitive dew point sensing—utilizing a temperature-controlled, polymer-based dielectric sensor whose capacitance shifts predictably with water vapor partial pressure. This enables direct, thermodynamically grounded measurement of dew point temperature (°C), which is then converted to ppmv (parts per million by volume) using user-defined gas composition and system pressure inputs. Designed for unattended operation in demanding production environments—including air separation units, petrochemical feed lines, instrument air networks, SF6-insulated switchgear, and compressed natural gas (CNG) drying systems—the MPS950 delivers metrologically traceable measurements down to –100 °C dew point, corresponding to sub-ppb-level moisture concentrations in dry nitrogen or argon.
Key Features
- Imported capacitive dew point sensor with long-term stability and minimal drift—calibration interval up to 12 months under typical operating conditions
- Simultaneous dual-parameter display: dew point temperature (°C) and moisture concentration (ppmv) with automatic compensation for sample pressure and gas type
- Configurable alarm outputs (high/low) with fully programmable setpoints across the full –100 to 0 °C range
- Standard 4–20 mA analog output with HART® protocol support (optional) for integration into DCS/SCADA systems
- Onboard data logging with timestamped records; historical data exportable via USB flash drive (FAT32 formatted)
- Ruggedized aluminum enclosure (IP65 rated) with internal temperature stabilization to mitigate ambient thermal influence on sensor performance
- Fast dynamic response: <10 seconds (90% step change) for dew points above –80 °C; <15 minutes for ultra-dry conditions below –80 °C, per ISO 8573-3:2010 test methodology
Sample Compatibility & Compliance
The MPS950 is validated for use with dry, non-corrosive gases including compressed air, nitrogen, argon, helium, oxygen (≤21% v/v), hydrogen, and SF6. It is explicitly not rated for CO2, chlorine, ammonia, or any gas containing condensable hydrocarbons or acidic components. All wetted parts are constructed from 316 stainless steel and PTFE-sealed fittings to ensure chemical inertness and prevent adsorption artifacts. The analyzer complies with IEC 61000-6-2 (EMC immunity) and IEC 61000-6-4 (EMC emissions), and meets CE marking requirements for industrial instrumentation. While not intrinsically safe, it may be deployed in Zone 2/Class I Div 2 areas when installed with appropriate barrier systems. Data integrity features—including audit-trail-enabled configuration changes and write-protected calibration logs—support alignment with GLP and GMP documentation practices per FDA 21 CFR Part 11 where electronic records are governed.
Software & Data Management
The MPS950 includes embedded firmware supporting local parameter configuration via front-panel keypad and LCD interface. Optional PC-based configuration software (MNK ConfigTool v3.x, Windows 10/11 compatible) enables advanced setup: custom gas matrix selection (N2, O2, Ar, SF6, etc.), pressure compensation curve adjustment, linearization coefficient tuning, and alarm logic sequencing. Logged data (up to 32,000 entries) includes dew point, ppmv, sample pressure, sensor temperature, and diagnostic flags (e.g., flow fault, sensor saturation). Exported .CSV files are compatible with LIMS platforms and statistical process control (SPC) tools. Firmware updates are performed via USB without hardware modification, ensuring long-term serviceability and regulatory maintainability.
Applications
- Continuous monitoring of instrument air quality in pharmaceutical manufacturing (per ISO 8573-1:2010 Class 2 or Class 3 compliance verification)
- Moisture surveillance in SF6 gas compartments of high-voltage circuit breakers and GIS systems (IEC 60480 / IEEE C37.122.1)
- Dryness validation in cryogenic air separation plant product streams (O2, N2, Ar) prior to liquefaction
- Trace moisture control in semiconductor fab nitrogen purge lines (target: <1 ppmv at –70 °C DP)
- Quality assurance of medical oxygen cylinders and bulk liquid oxygen delivery systems (USP guidance)
- Leak detection support in vacuum drying ovens and gloveboxes via rapid dew point rise analysis
FAQ
What gases are incompatible with the MPS950?
Carbon dioxide (CO2), chlorine, hydrogen sulfide, ammonia, and any gas containing condensable organics or strong oxidizers must be excluded—these may irreversibly poison the capacitive sensor or cause measurement hysteresis.
Is pressure compensation mandatory for accurate ppmv calculation?
Yes. The instrument requires user-input system pressure (in MPa or bar) to convert measured dew point to volumetric moisture concentration; error in pressure input directly propagates to ppmv uncertainty per the ideal gas law approximation.
Can the MPS950 be used in vacuum applications?
No. Its specified pressure range is 0–1 MPa (absolute), and it is not designed for sub-atmospheric sampling. Vacuum-line moisture monitoring requires dedicated low-pressure-capable analyzers with differential pumping or chilled-mirror technology.
Does the unit support NIST-traceable calibration?
Yes—MNK provides optional factory calibration certificates traceable to NIST SRM 2810 (water-in-nitrogen standards) or equivalent national metrology institute references, with uncertainty budgets reported per ISO/IEC 17025:2017.
