Intrinsically safe dew point instrument for hazardous locations

The Vaisala DMP370 series brings the company's proven DRYCAP® dew point technology into hazardous areas, pairing an interchangeable probe with the intrinsically safe HMT370EX transmitter. Rated for use up to Zone 0/20, the system is built for continuous, drift-compensated moisture monitoring in environments where flammable gases or dust may be present — including hydrogen production, natural gas and biomethane infrastructure, compressed air and nitrogen drying, and OEM integration into fuel cells, electrolyzers, and gas drying skids. The whole transmitter can be installed directly in the hazardous zone, and its detachable probe module lets probes be swapped or sent out for calibration without removing or reconfiguring the transmitter itself.

Key specifications and features:

• Intrinsically safe (Ex i) design, certified for operation up to Zone 0/20 (ATEX, IECEx, and other regional approvals)
• Vaisala DRYCAP® sensor for high accuracy, excellent long-term stability, and negligible hysteresis
• Dew point measurement range: −70 … +10 °C (−94 … +50 °F) Tdf, with accuracy of ±2 °C (3.6 °F) Tdf at +23 °C
• Temperature measurement range: −40 … +60 °C (−40 … +140 °F), accuracy ±0.1 °C (±0.18 °F) via Pt1000 RTD sensor
• Five interchangeable probe options to suit the application: DMP371 (wall mount), DMP374 (pressurized spaces), DMP375 (long probe), DMP377 (compact), and DMP378 (pressurized pipelines)
• Outputs an extensive set of calculated parameters beyond dew point, including absolute humidity, mixing ratio, wet-bulb temperature, water concentration, water vapor pressure, and enthalpy
• Graphical LCD display or non-display model available
• Traceable calibration certificate included
• Compatible with Vaisala Insight PC software and the Indigo80 handheld indicator