COMET C3121P – Thermo-Hygrometer with External Probe for Compressed Air Temperature & Humidity Measurement

COMET C3121P – Digital Thermo-Hygrometer with External Probe for Compressed Air Measurement, Temperature & Humidity, Dew Point, Min/Max Memory, Audible/Visual Alarm 

The COMET C3121P is a high-precision digital thermo-hygrometer specially designed for measuring temperature and relative humidity in compressed air systems – the ideal solution for quality control, monitoring, and documentation in compressors, adsorption dryers, refrigeration dryers, pneumatic systems, blow molding, paint booths, food and pharmaceutical production, or anywhere dew point and humidity in compressed air are critical. With an external probe for direct integration into pipelines, very high accuracy, and a traceable calibration certificate, it is perfect for audits, process optimization, and compliance with standards (e.g. ISO 8573).

The device measures temperature and humidity in compressed air using an external probe (measurement range depends on the probe, typically -30 to +105 °C / 0 to 100 %RH). The dew point is calculated automatically. The audible and visual alarm provides immediate warning if freely adjustable limits are exceeded. Min/Max memory displays the extreme values since the last power-on. The backlit LCD display is easy to read; measurement rate (0.7 to 5 s) and display update interval are adjustable. The robust housing (IP20) and battery power (9 V block or 12 V adapter with NiMH battery) make it mobile and independent of mains power – battery life approx. 4–6 months.

The thermo-hygrometer 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 via buttons and a clear menu. Whether used as a portable test instrument in service, a stationary monitor at compressors, or as a reference in production – the C3121P convinces with precision, flexibility, and ease of use. The external probe allows measurements directly in the compressed air stream.

Why the COMET C3121P is the best thermo-hygrometer for compressed air:

• Specially designed for compressed air – external probe for direct integration into pipelines
• High accuracy – Temp. ±0.4 °C | Humidity ±2.5 %RH
• Dew point calculation – essential for compressed air quality
• Audible and visual alarm – immediate warning when limits are exceeded
• Min/Max memory – extreme values since the last reset
• Backlit LCD display – easy to read even in poor lighting conditions
• Traceable calibration certificate included – maximum traceability
• Mobile battery power – approx. 4–6 months runtime (9 V block battery or NiMH rechargeable)
• Robust housing – for daily professional use
• 3-year warranty – COMET quality guaranteed

Technical data C3121P:

• External temperature: -30 to +105 °C (±0.4 °C)
• External humidity: 0 to 100 %RH (±2.5 %RH from 5 to 95 % at 23 °C)
• Dew point: -50 to +80 °C (±1.5 °C at T<25 °C and RH>30%)
• Resolution: 0.1 °C / 0.1 %RH / 0.1 °C dew point
• Alarm: audible + visual (adjustable thresholds)
• Min/Max memory: yes, with reset function
• Display: backlit LCD
• Measurement interval / display update: 0.7 to 5 s
• Power supply: 9 V block battery or 12 V adapter with NiMH 9 V battery
• Battery life: approx. 4–6 months
• Operating temperature: electronics -10 to +60 °C, external probe -30 to +105 °C
• Protection class: IP20 (device)
• Dimensions (without connector): 191 x 71 x 27 mm
• Weight (incl. battery): approx. 155 g
• Warranty: 3 years

Perfectly suited for:

• Compressed air systems and compressors
• Adsorption and refrigeration dryers
• Pneumatic and blow molding systems
• Paint booths and spray systems
• Food and pharmaceutical production
• Quality control according to ISO 8573
• Mobile testing and service
• Reference measurements and documentation

Installation and operation – ready to use immediately

Insert the external probe into the compressed air line or connect it, insert the battery or connect the power adapter – done! Set the limits, reset Min/Max – start measuring immediately. The backlit display and audible alarm ensure safe and comfortable operation. Calibration certificate included – ideal for audits and quality management.

Available versions:

• Cable length 1 meter
• Cable length 2 meters
• Cable length 4 meters

Summary:

• Thermometer and hygrometer for direct measurement of temperature and relative humidity in compressed air up to 25 bar
• Audible and visual alarm of measured values
• Storage of minimum and maximum values
• Hold function: Manual storage of measured values for later display
• Simultaneous measurement of temperature and relative humidity, selectable dew point measurement, external temperature and humidity probe

Scope of delivery:

• C3121P – depending on selected cable length
• User manual
• Traceable calibration certificate
• 9 V battery
• Plastic transport case