COMET D3631 External Thermo-Hygrometer Logger

COMET D3631 – Digital thermo-hygrometer with data logger, internal humidity 5–95 %RH (±2.5 %), input for external temperature probe -50 to +250 °C, dew point, 16,000 value memory 

The COMET D3631 is a professional digital thermo-hygrometer with an integrated data logger, internal humidity sensor, and external temperature probe – the ideal solution for long-term monitoring and documentation of indoor climate and process temperature in warehouses, climate chambers, cold stores, server rooms, museums, archives, greenhouses, pharmaceutical facilities, or anywhere humidity is measured internally and temperature must be recorded externally with flexibility. With a 16,000-value memory (non-cyclic or cyclic), freely adjustable logging interval (10 s to 24 h), and a traceable calibration certificate, it is perfect for quality management, audits, and long-term monitoring.

The internal humidity sensor measures 5 to 95 %RH (±2.5 %RH) and calculates the dew point (-40 to +60 °C, ±1.5 °C at T<25 °C and RH>30 %). The external temperature probe (Ni1000/Pt1000 – NOT INCLUDED) extends the range to -50 to +250 °C with high accuracy (±0.2 °C from -50 to +100 °C). The acoustic and optical alarm provides immediate warning when adjustable limits are exceeded. The Min/Max memory displays the extreme values. The Hold function allows manual storage of current readings for later display. The backlit LCD is easy to read, and both measuring rate (0.7 to 5 s) and display update are adjustable. The rugged housing (IP20) and battery power (9 V block or 12 V adapter with NiMH battery) make it mobile and independent – battery life approx. 6 months.

The free PC software enables simple data transfer via USB cable (for download only, no measurement during connection). Data can be displayed graphically, exported, and evaluated. The device is maintenance-free, long-term stable, and comes with a 3‑year warranty. The supplied traceable calibration certificate ensures maximum measurement accuracy from the factory. Intuitive operation using keys and a clear menu. Whether used as a mobile logger for field work, a continuous monitor in production, or a reference instrument in the laboratory, the D3631 impresses with precision, flexibility, and ease of use.

Why the COMET D3631 is the best thermo-hygrometer with external probe and data logger:

• 16,000 data memory – cyclic or non-cyclic
• Freely adjustable logging interval – 10 s to 24 h
• Internal humidity + external temperature – maximum flexibility
• High accuracy – Temp. ±0.2 °C | Humidity ±2.5 %RH
• Dew point calculation – ±1.5 °C at T<25 °C and RH>30 %
• Audible and visual alarm – instant warning when limits are exceeded
• Min/Max memory & Hold function – extreme values and manual storage
• Backlit LCD – easily readable even in poor lighting conditions
• Traceable calibration certificate included – highest traceability
• Portable battery operation – approx. 6 months lifetime (9 V block or NiMH battery)
• 3‑year warranty – guaranteed COMET quality

Technical data D3631:

• Humidity (internal): 5 to 95 %RH (±2.5 %RH at 23 °C)
• Temperature (external Ni1000/Pt1000): -50 to +250 °C (±0.2 °C from -50 to +100 °C / ±0.2 % above)
• Dew point: -40 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 (adjustable limits)
• Memory: 16,000 values (non-cyclic or cyclic)
• Logging interval: 10 s to 24 h (adjustable)
• Measurement interval / display update: 0.7 to 5 s
• Display: backlit LCD
• Power supply: 9 V battery or 12 V DC adapter with NiMH 9 V battery
• Battery life: approx. 6 months
• Operating temperature: -10 to +60 °C
• Protection class: IP20
• Dimensions (without connector): 191 × 71 × 27 mm
• Weight (including battery): approx. 155 g
• Warranty: 3 years

Perfect for:

• Long-term indoor climate monitoring in offices and warehouses
• Climate chambers and incubators
• Cold chain and pharmaceutical storage
• Food and beverage production
• Museums, archives, and sensitive storage areas
• Process monitoring and quality control
• Mobile humidity and temperature measurements in the field
• Reference measurements and documentation

Installation and operation – ready to use immediately

Connect the Ni1000/Pt1000 probe (not included), insert the battery or connect the power supply – done! Set the limit values, start recording – later transfer the data to a PC via USB. The backlit display and acoustic alarm ensure safe and convenient use. Calibration certificate included – ideal for audits and quality management.

Summary:

• Thermometer and hygrometer for measuring and recording temperature and relative humidity in internal non-volatile memory
• Free PC software enables transfer of recorded data to a computer for analysis
• LCD backlight
• The data logger connects to the PC via the supplied USB cable for data transfer only
• No measurements or logging possible while connected to the PC
• Simultaneous measurement of temperature and relative humidity; selectable dew point measurement; integrated sensors
• Cinch connector for external RTD temperature probe (Ni1000/6180 ppm – not included)
• Surface, penetration, and immersion probes with Cinch connector optionally available
• Display of temperature difference between external probe and dew point
• Audible and visual alarm for temperature difference – for example, to monitor condensation or mold formation

Scope of delivery:

• D3631
• User manual
• Traceable calibration certificate
• 9 V battery
• Mini USB cable
• Plastic transport case
• Self‑adhesive double lock for easy mounting
• Free full version of COMET Vision analysis software
• External Ni1000 temperature probe not included – order separately