Vaisala Handheld Dew Point Meter DM70
| Brand | Vaisala |
|---|---|
| Origin | Finland |
| Manufacturer | Vaisala Oyj |
| Product Type | Imported Industrial Dew Point Meter |
| Model | DM70 |
| Sensor Technology | Vaisala DRYCAP® Polymer Capacitive Sensor |
| Measurement Range | -60 to +60 °C dew point temperature (-76 to +140 °F) |
| Calibration | NIST-traceable certificate included |
| Data Logging | Internal memory with USB export via MI70 Link software |
| Environmental Protection | IP65-rated enclosure |
| Sampling Options | Multiple pressurized probe adapters available |
| Sensor Recovery | Automatic dry-out function for condensation recovery |
Overview
The Vaisala DM70 is a professional-grade, handheld dew point meter engineered for reliable, on-site moisture analysis in demanding industrial environments. Utilizing Vaisala’s proprietary DRYCAP® polymer capacitive sensing technology, the DM70 measures dew point temperature—the temperature at which air becomes saturated with water vapor—based on the fundamental thermodynamic relationship between moisture content and saturation pressure. This principle enables high-accuracy, real-time quantification of water vapor concentration in gases such as compressed air, nitrogen, natural gas, and process drying streams. Designed specifically for field use, the DM70 delivers laboratory-grade metrological performance without requiring fixed installation or external power sources. Its robust, IP65-rated housing ensures operational integrity in dusty, humid, or intermittently wet conditions typical of manufacturing floors, HVAC maintenance zones, and packaging line environments.
Key Features
- DRYCAP® sensor with integrated automatic calibration algorithm that compensates for long-term drift without manual intervention
- Condensation-tolerant design: sensor recovers autonomously after exposure to transient liquid water or high-humidity excursions
- Onboard data logging with timestamped records (up to 1,000 measurements), exportable via USB to PC using MI70 Link software
- NIST-traceable calibration certificate supplied with each unit, supporting ISO/IEC 17025-compliant quality systems
- Dry-out function accelerates sensor response time following condensation events by applying controlled thermal energy
- Ergonomic, single-hand operation with backlit LCD display and intuitive push-button interface
- Interchangeable sampling accessories—including stainless steel flow-through probes, pressure-rated adapters (up to 16 bar), and desiccant-filtered inlets—for direct connection to pressurized pipelines or ambient ducts
Sample Compatibility & Compliance
The DM70 is validated for use with non-corrosive, non-condensing gas matrices including compressed air (oil-free and lubricated), instrument air, nitrogen blanketing gas, SF6 switchgear gas, and dry process air in plastic granule drying systems. It complies with ISO 8573-1:2010 Class 2–4 moisture specifications for compressed air quality and supports verification against ASTM D6304 (moisture in petroleum products) and ISO 12500-3 (compressed air filter testing). The instrument meets CE marking requirements under the EU Measuring Instruments Directive (MID) and conforms to electromagnetic compatibility standards EN 61326-1. Its calibration traceability aligns with international metrology frameworks required for FDA 21 CFR Part 11–governed pharmaceutical facilities and GLP/GMP audit trails.
Software & Data Management
MI70 Link is a Windows-based configuration and data retrieval utility enabling full control over logging intervals, alarm thresholds, and unit preferences (°C dp, ppmv, g/m³, psiv). Exported CSV files include metadata such as serial number, calibration date, ambient temperature, and pressure compensation status—essential for audit-ready documentation. The software supports batch import into LIMS or MES platforms via standard ODBC drivers. All measurement sessions retain digital signatures and immutable timestamps, satisfying electronic record retention requirements per 21 CFR Part 11 Annex 11 and ISO 13485 clause 7.5.10.
Applications
- Compressed air system validation and routine monitoring in food & beverage, automotive, and electronics manufacturing
- In-line moisture verification during PET bottle preform drying and hygroscopic polymer processing (e.g., nylon, polycarbonate)
- Preventive maintenance of refrigerant and desiccant dryers through trend analysis of dew point excursions
- Commissioning and commissioning verification of cleanroom HVAC systems per ISO 14644-1
- Field calibration verification of permanently installed dew point transmitters (e.g., Vaisala DM80, GE Panametrics)
- Moisture diagnostics in transformer oil gas analysis (DGA) sample handling systems
FAQ
Does the DM70 require periodic factory recalibration?
Yes—while the DRYCAP® sensor self-compensates for baseline drift, Vaisala recommends annual recalibration against primary chilled-mirror reference standards to maintain traceability per ISO/IEC 17025.
Can the DM70 measure dew point under pressure?
It does not directly measure under pressure; however, when used with optional pressurized sampling probes (e.g., DM70-P), it accepts gas at up to 16 bar and applies real-time pressure compensation using integrated absolute pressure sensing.
Is the MI70 Link software compatible with macOS or Linux?
No—MI70 Link is exclusively supported on Windows 10/11 (64-bit) with .NET Framework 4.8. Data files (CSV) are platform-agnostic and can be imported into cross-platform analytics tools.
What is the typical response time (T90) after a step change in dew point?
At 20 °C ambient and 0 °C dew point, T90 is ≤ 4 minutes; response accelerates significantly when the dry-out function is activated following condensation exposure.
How is sensor contamination mitigated during long-term field deployment?
The DRYCAP® polymer film is chemically inert to most industrial VOCs and oils; optional sintered stainless-steel inlet filters (part no. 213126) provide particulate protection without affecting accuracy.
