COMET T5440 - CO₂ Transmitter RS485 with LED Indicator

COMET T5440 – precise CO₂ transmitter      

The COMET T5440 is a compact and reliable CO₂ concentration transmitter designed for professional indoor air quality monitoring. Its high-quality NDIR sensor precisely measures carbon dioxide concentration from 0 to 5000 ppm and, thanks to the integrated 3-color LED indicator, immediately shows the current air quality: Green = good (up to 1000 ppm), Yellow = moderate (1001–1200 ppm), Red = poor (from 1201 ppm).

Ideal for offices, schools, conference rooms, production areas, warehouses, or any location where many people gather — ensuring demand-controlled ventilation that saves energy and promotes health. The maintenance-free sensor with automatic calibration guarantees years of accuracy without readjustment.

The RS485 interface with Modbus RTU protocol (factory-installed) allows seamless integration of the T5440 into any building automation, ventilation control, or SCADA system. The robust housing is designed for continuous operation from –30 to +60 °C — perfect for unheated technical rooms or corridors.

Compact, discreet, and easy to install — the T5440 is the smart solution for modern indoor air monitoring.

Why the COMET T5440 is the best choice for CO₂ monitoring:

• Precise NDIR CO₂ sensor 0–5000 ppm (±50 ppm + 3%)
• 3-color LED indicator – instantly visible air quality
• RS485 Modbus RTU (factory) – ideal for building automation
• Maintenance-free thanks to automatic calibration
• Optional extended range up to 10,000 ppm (extra cost)
• Rugged housing – operating temperature –30 to +60 °C
• Compact dimensions 88.5 × 94 × 39.5 mm
• Easy wall mounting
• Lightweight, approx. 145 g
• 3-year warranty

Technical data:

• CO₂ measuring range: 0 to 5000 ppm
• CO₂ accuracy: ±(50 ppm + 3% of measured value) at 25 °C and 1013 hPa
• CO₂ resolution: 1 ppm
• LED indicator: Green ≤1000 ppm | Yellow 1001–1200 ppm | Red ≥1201 ppm
• Communication: RS485, Modbus RTU, ARION, Advantech ADAM
• Power supply: 9–30 V DC
• Operating temperature: –30 to +60 °C
• Protection rating: IP30
• Dimensions: 88.5 × 94 × 39.5 mm
• Weight: approx. 145 g
• Warranty: 3 years

Perfectly suited for:

• Schools, kindergartens, lecture halls
• Offices, open-plan offices, call centers
• Conference and meeting rooms
• Production and storage halls
• Restaurants, fitness centers, wellness areas
• Hospitals, waiting rooms
• Demand-controlled ventilation systems
• Building automation and energy management

Installation – done in minutes

Mount to the wall using two screws, connect power and RS485 – done. The LED indicator immediately displays the current CO₂ level.

Summary:

• CO₂ sensor (carbon dioxide level transmitter)
• Green LED on: CO₂ concentration 0 to 1000 ppm
• Yellow LED on: CO₂ concentration 1001 to 1200 ppm
• Red LED on: CO₂ concentration 1201 ppm and higher

Scope of delivery:

• T5440
• User manual
• Traceable calibration certificate
• Free TSensor software for transmitter configuration