COMET U3430 – Data logger with internal sensors for temperature, humidity, CO₂, and dew point

COMET U3430 – robust data logger with internal sensors (-20 to +60 °C ±0.4 °C / 0–100 %RH ±1.8 % / CO₂ 0–5000 ppm ±(50 ppm + 3%)), dew point 

The COMET U3430 is a compact and highly accurate data logger with integrated sensors for temperature, relative humidity, and CO₂ – the ideal solution for self-contained long-term monitoring and documentation of indoor air quality in offices, schools, kindergartens, hospitals, server rooms, warehouses, conference rooms, living spaces, greenhouses, or anywhere temperature, humidity, and CO₂ concentration are critical and must be recorded. With a huge memory capacity of 500,000 values (non-cyclic) or 350,000 values (cyclic), freely adjustable recording interval (1 s to 24 h), and traceable calibration certificate (EN ISO/IEC 17025), it is perfect for quality management, audits, workplace monitoring, and occupational safety.

The internal temperature sensor measures from -20 to +60 °C (±0.4 °C), the humidity sensor 0 to 100 %RH (±1.8 %RH), and the CO₂ sensor 0 to 5000 ppm (±(50 ppm + 3 % of the measured value) at 25 °C and 1013 hPa). The dew point is calculated automatically (-60 to +60 °C, ±1.5 °C at T<25 °C and RH>30 %). The acoustic and optical alarm (buzzer + LED) immediately warns when freely adjustable limits are exceeded. Min/Max values are stored. The backlit LCD display is easy to read, and the measurement/alarm update rate can be set (1 s, 10 s, 1 min). The logger operates independently with a 3.6 V AA lithium battery – service life of several years depending on the interval. No power supply required – ideal for fixed and mobile installations. Recording can be non-cyclic (stops when memory is full) or cyclic (overwrites oldest data). Real-time clock with date/time. Data transfer to PC via USB-C (COMET Vision software).

The data logger is maintenance-free, long-term stable, and comes with a 3-year warranty. The included traceable calibration certificate guarantees the highest measurement accuracy from the factory. Intuitive operation via buttons and a clear menu. The compact housing (61 x 93 x 32 mm) makes it discreet and easy to mount. Whether used as a standalone logger in production, a mobile tester in service, or a fixed part of indoor air monitoring – the U3430 impresses with precision, robustness, and ease of use. No external probe required – ready for immediate indoor measurement.

Why the COMET U3430 is the best data logger for T+RH+CO₂:

• Internal sensors for T+RH+CO₂ – ready for use without a probe
• 500,000 measurement value memory – non-cyclic or cyclic
• Recording interval freely adjustable – 1 s to 24 h
• Acoustic & optical alarm – immediate warning in case of limit violation
• Min/Max memory – extreme values for all parameters
• Backlit LCD – temperature, humidity, CO₂ and status readable
• Traceable calibration certificate included – EN ISO/IEC 17025
• Self-contained battery operation – lithium AA, lifetime several years
• USB-C data transfer – easy reading via COMET Vision
• 3-year warranty – COMET quality guaranteed

Technical data U3430:

• Temperature internal: -20 to +60 °C (±0.4 °C)
• Humidity internal: 0 to 100 %RH (±1.8 %RH)
• CO₂ internal: 0 to 5000 ppm (±(50 ppm + 3 % of the measured value) at 25 °C and 1013 hPa)
• Dew point: -60 to +60 °C (±1.5 °C at T<25 °C and RH>30 %)
• Resolution: 0.1 °C / 0.1 %RH / 1 ppm CO₂ / 0.1 °C dew point
• Channels: internal sensors for temperature, humidity, CO₂
• Memory: 500,000 values (non-cyclic) / 350,000 values (cyclic)
• Recording interval: 1 s to 24 h
• Measurement/alarm update: adjustable 1 s, 10 s, 1 min
• Alarm: acoustic (buzzer) + optical (LED) on limit violation
• Display: backlit LCD
• Power supply: lithium battery 3.6 V AA
• Operating temperature: -20 to +60 °C
• Protection class: IP20
• Dimensions: 61 x 93 x 32 mm
• Weight (incl. battery): approx. 120 g
• Warranty: 3 years

Perfectly suited for:

• Indoor air quality in offices, schools & hospitals
• Server rooms and data centers
• Storage and cold room monitoring
• Pharmaceutical and food production
• Climate chambers and incubators
• Greenhouses & agriculture
• Quality management & audits
• Self-contained long-term logging without mains power

Mounting and operation – done in minutes

Insert the battery – done! Set intervals and limits, start logging – read data via USB-C. The backlit display and acoustic/optical alarm make operation safe and convenient. Calibration certificate included – ideal for audits and quality management.

Summary:

• The data logger is designed for recording temperature, humidity, and CO₂
• If set limits are exceeded, an alarm is triggered via LED, LCD display, and acoustic signal
• Recording is stored in non-volatile electronic memory
• Data can be transferred to a PC via USB-C
• The recorder includes a traceable calibration certificate, the metrological traceability of which has been proven according to EN ISO/IEC 17025 requirements.

Delivery contents:

• U3430
• User manual
• Traceable calibration certificate
• Battery
• Power supply
• USB-C cable
• Free full version of COMET Vision analysis software