Portable Logger Thermohygrometer Vaisala HM70

Professional‑grade portable thermohygrometer with integrated data logging designed for fast, reliable spot checks and long‑term monitoring. The Vaisala HM70 leverages industry‑leading HUMICAP sensor technology to deliver stable, repeatable humidity and temperature measurements in laboratories, cleanrooms, HVAC commissioning, pharmaceuticals, food processing and demanding industrial environments. With interchangeable probes for different conditions, a clear backlit display and on‑site calculation of dew point and other psychrometric parameters, the HM70 helps you make the right decisions at the first visit and reduce rework. Choose the HM70 at Stratosens.com for a robust, accurate and easy‑to‑use instrument that supports your quality standards and compliance.

Key Benefits and Applications

• Trusted accuracy in critical environments. The HUMICAP sensing technology is renowned for low drift and excellent long‑term stability, helping you maintain tight environmental tolerances in GMP suites, calibration labs and high‑value storage areas.
• One instrument for many tasks. Use interchangeable probes to measure in ducts, rooms, incubators, chambers or high‑temperature processes, so technicians can cover multiple jobs with a single platform.
• Measure, calculate and validate on site. View relative humidity, temperature and derived values such as dew point, wet‑bulb temperature, mixing ratio, absolute humidity and enthalpy directly on the instrument to validate conditions without extra tools.
• Portable logging for traceability. The integrated memory records time‑stamped measurements for later review, supporting audits and documentation in regulated industries.
• Fast response and productivity. Smart probe design and quick stabilization minimize waiting time between points, allowing more measurements per visit and lower cost per site.
• Rugged, field‑ready build. A robust housing, protective accessories and intuitive menus withstand daily use, from commissioning new HVAC systems to routine preventive maintenance rounds.
• Easy data transfer and reporting. Connect to a PC to download logs, create reports and archive data, streamlining handover to quality teams and clients.

Featured technical specifications

• Measured parameters. Relative humidity in %RH and temperature in °C. On‑device calculations include dew point temperature in °C, wet‑bulb temperature in °C, mixing ratio in g/kg, absolute humidity in g/m³, water vapour pressure in Pa and enthalpy in kJ/kg.
• Relative humidity range. Full range from 0 %RH to 100 %RH, suitable for dry rooms through to high‑humidity processes.
• Temperature capability. Wide application coverage with probe options. Typical use spans room conditions and extends to deep‑cold or high‑temperature environments up to approximately +180 °C with the appropriate high‑temperature probe.
• Sensor technology. Vaisala HUMICAP thin‑film capacitive sensor offers excellent repeatability, low hysteresis and long‑term stability for dependable results between calibrations.
• Interchangeable probes. Short, long and remote stainless‑steel probes are available to optimize access in ducts, chambers and process installations. Probes can be swapped without complex setup to keep technicians productive.
• Data logging. Built‑in memory stores time‑stamped measurement series at a user‑selectable interval so you can document trends and verify compliance over a shift or campaign.
• Display and user interface. Large, backlit graphical display shows multiple parameters at once with clear trend indication, minimum and maximum values and a practical hold function for note‑taking.
• Pressure compensation. Manual pressure input improves calculated humidity parameters when measurements are taken in processes that deviate from standard atmospheric pressure.
• Power and portability. Handheld form factor with long battery operation and an external power option supports full‑day field work and bench use.
• Calibration and adjustment. Supports one‑ or multi‑point user adjustments to align with reference standards. Traceable calibration services are available to maintain confidence and documentation.
• Connectivity. PC connectivity enables data download and configuration, simplifying reporting and archiving in your digital workflows.
• Construction. Durable housing and probe materials are designed for professional use in laboratories and industrial facilities where reliability is essential.

Why this thermohygrometer is the perfect choice

Pairing proven HUMICAP performance with practical portability, the Vaisala HM70 gives you confidence in every reading while reducing time on site. At Stratosens.com you receive expert pre‑ and post‑sales support, fast delivery and calibration options tailored to your quality system, so your team can deploy a reliable thermohygrometer that is ready to work from day one and stay accurate over the long term.