COMET U3120M – IoT Wireless Datalogger with 2G Modem, Internal Temperature and Humidity Measurement

COMET U3120M – IoT Wireless Datalogger with 2G Modem, internal T+RH (-20 to +60 °C ±0.4 °C / 0–100 %RH ±1.8 %), Dew Point, SMS/JSON Alarm

The COMET U3120M is a modern IoT wireless datalogger with an integrated 2G modem (Quad‑Band GSM/GPRS) – the autonomous and network‑independent solution for remote monitoring and long‑term recording of temperature, relative humidity, and dew point using internal sensors. Whether in cold‑chain logistics, warehouses, climate chambers, server rooms, greenhouses, offices, hospitals, archives, or remote sites, the U3120M sends an SMS and JSON alarm immediately via GPRS when preset limits are exceeded. Regular JSON data transfer to COMET Database or COMET Cloud (a comprehensive monitoring, alarm, and analysis platform) can be configured. On‑site alarm is indicated by LED, LCD, and buzzer. With a memory capacity of 1 million values (non‑cyclic) or 600,000 values (cyclic) and a traceable calibration certificate (EN ISO/IEC 17025), it is ideal for quality management, audits, and ISO compliance.

The internal sensors measure temperature from −20 to +60 °C (±0.4 °C) and humidity from 0 to 100 %RH (±1.8 %RH). The dew point is calculated automatically (−90 to +60 °C, ±1.5 °C at T<25 °C and RH>30 %). The acoustic and optical alarms give immediate warning when configurable limits are exceeded. Min/Max values are stored. The illuminated LCD display is easy to read, and measurement rate (0.7 to 5 s) and display refresh rate are adjustable. The logger operates completely independently using an internal battery – no external power supply required. Data can be downloaded to a PC via USB‑C. COMET Cloud: 3 months free, then 1 credit per year. The Quad‑Band GSM modem (850/900/1800/1900 MHz) ensures global coverage and reliable data communication.

The datalogger is maintenance‑free, long‑term stable, and comes with a 3‑year warranty. The supplied traceable calibration certificate guarantees maximum accuracy from the factory. Configuration is intuitive via LCD or COMET Cloud. Whether used as a mobile remote logger on construction sites, a stationary monitor in buildings, or a central device in facility management – the U3120M impresses with precision, autonomy, 2G connectivity, and ease of use. No external probe required – ready to use immediately for indoor measurements.

Why the COMET U3120M is the best IoT 2G datalogger for T+RH:

• Integrated 2G modem (Quad‑Band GSM/GPRS) – SMS/JSON alarm & data transfer without Wi‑Fi/LAN
• Internal T+RH sensors – ready to use without external probe
• 1 million data values – non‑cyclic or cyclic recording
• COMET Cloud – full monitoring, alarm & analysis (3 months free)
• Acoustic/optical alarm + LED – immediate on‑site warning
• Dew point & all humidity parameters – automatically calculated
• Backlit LCD – all values viewable simultaneously
• Traceable calibration certificate included – EN ISO/IEC 17025
• Battery‑powered autonomy – no external power needed
• 3‑year warranty – guaranteed COMET quality

Technical Data U3120M:

• Internal temperature: −20 to +60 °C (±0.4 °C)
• Internal humidity: 0 to 100 %RH (±1.8 %RH)
• Dew point: −90 to +60 °C (±1.5 °C at T<25 °C and RH>30 %)
• Resolution: 0.1 °C / 0.1 %RH / 0.1 °C dew point
• Alarm: acoustic + optical + SMS/JSON via GPRS
• Memory: 1,000,000 values (non‑cyclic) / 600,000 values (cyclic)
• Logging interval: 1 s to 24 h
• Measurement interval / display refresh: 0.7 to 5 s
• Display: backlit LCD
• Communication: 2G modem (Quad‑Band 850/900/1800/1900 MHz, GPRS Class B) + USB‑C
• Power supply: internal battery (lifetime dependent on configuration – several months or years)
• Operating temperature: −20 to +60 °C
• Protection class: IP20 (device)
• Warranty: 3 years

Perfect for:

• Cold‑chain & transport monitoring (remote temperature & humidity)
• Warehouse and cold‑room monitoring
• Pharmaceutical and food production
• Server rooms and data centers
• Greenhouses & agriculture
• Offices, schools & hospitals (ambient air monitoring)
• Remote monitoring without local internet connection
• Quality management & audits

Setup and operation – done in minutes

Activate the battery, insert SIM card (if desired) – done! Configure intervals, limits, and Cloud/SMS settings, start logging – read data via COMET Cloud or USB‑C. The backlit display and acoustic alarm ensure safe and convenient operation. Calibration certificate included – ideal for audits and quality management.

Summary:

• The GSM datalogger records temperature and humidity using integrated sensors
• When limits are exceeded, SMS and JSON messages are sent via a GPRS data connection
• Measured values can be transmitted to COMET Cloud – a comprehensive monitoring, alarm, and analysis system
• Regular JSON data transmission to the COMET Database can also be configured; the sending interval is adjustable
• Alarms are locally indicated via LED, LCD, and an integrated sound signal
• Logging is stored in non‑volatile electronic memory
• Data can be downloaded to a PC using the supplied USB‑C cable
• The GSM recorder includes a traceable calibration certificate confirming metrological traceability according to EN ISO/IEC 17025
• When purchasing a new IoT wireless datalogger with an integrated modem, you get 3 months of free COMET Cloud access; for a full operational year, 1 credit is required.

Scope of delivery:

• U3120M
• User manual
• Traceable calibration certificate
• Battery
• Power adapter
• USB‑C cable
• Free full version of COMET Vision analysis software
• COMET Cloud for 3 months
• SIM card not included