Belimo room sensor for CO₂, humidity and temperature - MP-Bus - 22RTM-18-1

Belimo Room Sensor for CO₂, Humidity and Temperature - MP-Bus - 22RTM-18-1

The Belimo 22RTM-18-1 (RAL 9003) is a room sensor and control module designed for simultaneous measurement of CO₂, relative humidity and temperature in occupied spaces. Thanks to MP-Bus communication and three configurable analogue outputs, the sensor integrates seamlessly with existing controllers from other manufacturers. Using the Belimo Display App, users can read current measurement values and set desired parameters via their smartphone. The CO₂ measurement utilises NDIR dual-channel technology, eliminating the need for regular outdoor air calibration. Commissioning and configuration are straightforward via the Belimo Assistant 2.

Advantages and Features

• Triple measurement in one sensor: The room sensor simultaneously measures CO₂ (0–2000 ppm), relative humidity (0–100% RH) and temperature (0–50°C), reducing wiring and installation costs compared to separate sensors.
• NDIR dual-channel CO₂ technology: A built-in reference channel automatically corrects measurement drift common to all CO₂ sensors over time, removing the need for regular outdoor air calibration, even with 24/7 occupancy.
• MP-Bus communication: Up to 8 sensors can be connected on a single MP-Bus, with power and communication through the same cable, significantly reducing wiring costs.
• Operation via Belimo Display App: Read current measurements and adjust setpoints by holding your smartphone close to the sensor.
• CO₂ traffic light function: The integrated LED visually indicates air quality in green, yellow and red, giving occupants immediate insight into the room’s ventilation needs.
• Three configurable analogue outputs: The outputs can be set to 0–10 V, 2–10 V, 0–5 V or 4–20 mA, ensuring compatibility with virtually all existing controllers.
• Simple wall mounting: Mounts on a standard flush-mounted box with cable entry at the rear, top or bottom, allowing wiring to be concealed or visible within the wall.

Installation, Maintenance and Applications

The sensor is mounted on the wall using the supplied screws, preferably in a representative location free from direct sunlight, drafts and heat sources. Electrical connection is made via spring terminals suitable for cables from 0.2 to 2.5 mm². Configuration of measurement ranges, analogue outputs and the CO₂ traffic light function is performed via the Belimo Assistant 2 app. It is recommended to recalibrate the CO₂ sensor after five years of operation. This room sensor is ideally suited for ventilation in offices, meeting rooms, classrooms, hotel rooms and healthcare facilities where air quality, humidity control and energy saving are priorities.