CO2 sensors modbus rs485

 NBL-W-CO2 Carbon Dioxide Sensor with Modbus RS485 Product Introduction

The NBL-W-CO2 Carbon Dioxide Sensor utilizes an imported high-precision sensor chip to measure CO2 concentrations in various environments, offering high accuracy and excellent stability. Equipped with an advanced integrated circuit module, it supports multiple output formats, including 4–20mA and RS485 with Modbus RTU protocol, for seamless integration into smart monitoring systems. Its compact design (weighing only 140g), easy installation, and reliable performance make it ideal for CO2 monitoring in offices, public spaces, greenhouses, and industrial plants.

 Working Principle of CO2 Sensor

The NBL-W-CO2 sensor employs Non-Dispersive Infrared (NDIR) technology, measuring CO2 concentration by detecting the absorption of infrared light at a specific wavelength. This method ensures high stability and strong anti-interference capabilities, making it one of the leading techniques for CO2 detection. 

 CO2 Sensor Technical Specifications

- Range: 0–5000 ppm  

- Resolution: 1 ppm  

- Accuracy: ±(50 ppm + 3%F.S.)  

- Output: 4–20mA, RS485 (Modbus RTU)  

- Power Supply: DC 12V–24V  

- Operating Conditions: -10°C to 50°C, 0–100%RH  

- Power Consumption: 0.2W  

- Cable Length: Standard 2.5m  

- Weight: 140g  

 Advantages of Modbus RS485 CO2 Sensor

1. Long-Distance Transmission: RS485 supports communication distances over 1000 meters with industrial-grade data transmission.  

2. Multi-Device Networking: Connects multiple devices for centralized control.  

3. Strong Anti-Interference: Differential signal transmission ensures reliability in complex industrial environments.  

4. Open Protocol: Compatible with mainstream PLCs and environmental monitoring systems.  

5. Flexible Power Supply: Supports wide voltage input (DC 12V–24V).  

 Application Scenarios for CO2 Sensors with Modbus RS485

- Greenhouses: Regulates CO2 levels to enhance plant photosynthesis and growth.  

- Office Buildings: Monitors air quality to ensure employee health and comfort.  

- Industrial Workshops/Warehouses: Prevents CO2 accumulation in confined spaces.  

- Public Spaces: Manages air quality in hospitals, schools, and malls.  

- Smart Buildings and HVAC Systems: Enables centralized monitoring and automated ventilation adjustments.  

 Installation Instructions for CO2 Sensors with Modbus RS485

1. Installation Location: Mount at 1.5–2 meters above ground for accurate air quality representation.  

2. Mounting Method: Secure with screws or clips on walls or control cabinets.  

3. Wiring: Connect RS485 A/B terminals to the communication bus and power terminals to DC 12–24V supply.  

4. Commissioning: Set the Modbus address and baud rate for system integration.   

 Modbus RS485 Communication Details

1. Communication Protocol:  

   The NBL-W-CO2 sensor uses the Modbus RTU protocol, a widely adopted, open serial communication standard for industrial automation. It supports master-slave communication, integrating seamlessly with PLCs, industrial PCs, and software like KingView or LabVIEW.  

2. Baud Rate and Parameter Configuration:  

   - Supported baud rates: 4800, 9600, 19200, 38400  

   - Default parameters: 8 data bits, 1 stop bit, no parity (8N1)  

   - Remote configuration of address or baud rate to meet diverse system requirements.   

3. Multi-Device Communication:  

   RS485 supports up to 32 devices on a single bus (expandable with repeaters). Unique device addresses enable centralized monitoring of multiple sensors, reducing wiring costs.   

4. Electrical Characteristics and Wiring Recommendations:  

   - Use twisted-pair shielded cables to enhance anti-interference performance.  

   - Install a 120Ω termination resistor at the end device to prevent signal reflection.  

   - Ensure correct A/B line connections to avoid communication issues.  

 Summary

The NBL-W-CO2 is a high-performance, easily integrated CO2 sensor with Modbus RS485 communication, ideal for industrial, agricultural, and commercial applications. Its high accuracy, anti-interference capabilities, and long-distance communication make it a top choice for smart air quality monitoring systems. With a compact design, low power consumption (0.2W), and compatibility with mainstream systems, it supports greenhouse management, office air quality, industrial safety, and smart building applications, providing global customers with a reliable and efficient CO2 monitoring solution.

Carbon dioxide sensor(CO2 sensor) data sheet：

NBL-W-CO2-Carbon-Dioxide-Sensor-Instruction-Manual-2000ppm.pdf

NBL-W-CO2 Carbon-Dioxide-Sensor-Instruction-Manual-5000ppm.pdf