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Wi-Fi Data Logger (FDA approved)

The Vaisala HMT140 wireless data logger is designed for humidity, temperature and analog signal monitoring in warehouses, freezer and cryogenic farms, laboratories, blood banks and many other life science applications.

The Vaisala HMT140 incorporates Vaisala HUMICAP® technology to measure relative humidity and temperature accurately and reliably. The Vaisala HUMICAP sensor is resistant to dust and most chemicals. Alternatively, the Vaisala HMT140 can connect to Resistance Temperature Detectors (RTDs), Voltage, Current and Contact sensors, making the Vaisala HMT140 the most versatile Vaisala data logger for life science applications.

Combining RTD and contact inputs, the Vaisala HMT140 is ideal for monitoring chamber/door excursions. Using Wi-Fi connectivity, the Vaisala HMT140 can connect through any wireless access point. The battery powered logger can operate for 18 months continuously, or longer if using the batteries only as backup to an optional external power source.

Optional local display allows the Vaisala HMT140 to indicate process parameter values and any limit warnings. All data is logged locally and uploaded to the Vaisala Continuous Monitoring System (CMS) software at preset intervals and during parameter excursions.

Autonomous operation with audible and visual alarming (beep and flashing LED) ensures that local alerts are indicated independent of active network or server connection.

The data logger's enclosure is optimized for use in cleanrooms with a surface that is easy to clean and tolerates purifying agents.

Technical Specs

Model Vaisala HMT140
Fixed / Portable Fixed and Portable
Measurement Range -40 °C ... +80 °C
Accuracy at +15 °C ... +25 °C ±0.2 °C; at 0 ... +15 °C and at +25 °C ... +40 °C ±0.25 °C; at -40 °C ... +0 °C and at +40 °C ... +80 °C ±0.4 °C
Remarks ▪ Wi-Fi connectivity to Vaisala's Continuous Monitoring system

▪ Connectivity provided through existing Wi-Fi Access Points

▪ Autonomous operation and local alarms ensure alerting capability regardless of network connectivity

▪ Local data storage provides continuous fail-safe operation

▪ 18-month battery operation

▪ Vaisala HUMICAP® technology with humidity sensor HUMICAP® 180R

▪ Interchangeable temperature/RH probe for easy field calibration

▪ Two inputs available: voltage, current, contact, RTDs or temperature & RH

▪ Accurate and reliable multi-signal measurements

▪ Resistant to dust and most chemicals

▪ Optional LCD display

▪ Wall-mounted or with remote probes

▪ NIST-traceable (certificate included)

▪ Ideal for cleanrooms and other life science applications

Data sheet


See also
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