COMET T3117 – 4-20mA Transmitter with 700 mm Probe for Temperature and Humidity

COMET T3117 – 4-20mA Transmitter with 700 mm long rod probe for temperature –30 to +125 °C, humidity 0–100 %RH, dew point 

The COMET T3117 is a professional 4-20mA transmitter with an extra-long 700 mm rod probe for temperature, relative humidity, and dew point – the ideal solution for precise measurement deep in the airflow of large ventilation and air conditioning systems (HVAC), air ducts, supply or exhaust systems, climate chambers, drying plants, silos, or process air. With a galvanically isolated current output (4-20 mA) and high long-term stability, it is perfect for connection to PLCs, building management systems, controllers, recorders, or remote monitoring – even over long distances without signal loss.

The 700 mm long rod probe extends deep into the duct and provides representative readings even in very large cross-sections or with laminar airflow. Temperature is measured from –30 to +125 °C (±0.4 °C), humidity from 0 to 100 %RH (±2.5 %RH from 5–95 % at 23 °C). Dew point is calculated internally (±1.5 °C at T<25 °C and RH>30 %). All other humidity parameters are additionally available: absolute humidity, specific humidity, mixing ratio, and specific enthalpy. The output is freely scalable – you define via PC the measuring range and which parameter (T, RH, Tdp, etc.) is transmitted.

The robust IP65 housing (electronics) and the IP40 sensor make the T3117 a reliable partner for demanding use in ducts and ventilation systems (–30 to +80 °C). Galvanic isolation protects against ground loops and interference. The sensors are long-term stable and available with a traceable calibration certificate (according to EN ISO/IEC 17025) – top quality for critical applications. Power supply 9–30 V DC – simple and flexible.

Why the COMET T3117 is the professional long-rod transmitter:

• 700 mm extra-long rod probe – optimal measuring position in large ducts
• Galvanically isolated 4-20mA output – interference-proof & PLC-compatible
• 3-in-1: Temperature + Humidity + Dew point – all humidity parameters available
• High precision – Temp. ±0.4 °C | Humidity ±2.5 %RH | Dew point ±1.5 °C
• Freely scalable – configurable via PC (measured parameter & range)
• IP65 electronics + IP40 probe – for harsh duct environments
• Wide supply voltage – 9–30 V DC
• Long-term stable & maintenance-free – with calibration certificate

Technical data T3117:

• Temperature range: –30 to +125 °C (±0.4 °C)
• Humidity: 0 to 100 %RH (±2.5 %RH from 5–95 % at 23 °C)
• Dew point: –60 to +80 °C (±1.5 °C at T<25 °C and RH>30 %)
• Output: 4-20 mA, galvanically isolated
• Resolution: 0.1 °C / 0.1 %RH
• Rod probe length: 700 mm
• Power supply: 9–30 V DC
• Operating temperature: –30 to +80 °C
• Protection: IP65 (electronics), IP40 (probe)
• Dimensions: 88.5 × 94 × 39.5 mm
• Weight: approx. 580 g
• Warranty: 3 years

Perfectly suited for:

• Large ventilation and air conditioning systems (HVAC)
• Air ducts with large cross-sections
• Climate chambers and drying systems
• Data centers and server rooms (supply air)
• Production and storage halls
• 4-20mA connection to PLC/BMS
• Demand-controlled ventilation
• Integration into existing analog systems

Installation & commissioning – done in minutes

Mount the device to the duct (hole Ø 25 mm), connect power (9–30 V DC) and 4-20mA loop – done! Configure the output via PC (COMET software) to define which parameter and range are transmitted. No calibration effort when replacing the device.

Summary:

• Humidity and temperature transmitter
• For indoor and outdoor use
• Rod-type design
• Sensors for relative humidity and temperature (700 mm rod length)
• Measured values are also converted into other humidity parameters: dew point temperature, absolute humidity, specific humidity, mixing ratio, specific enthalpy.

Scope of delivery:

• T3117
• User manual
• Traceable calibration certificate
• Free TSensor software for transmitter configuration