Additional specifications and description
CO2 measurements in air ducts
Animals and people produce CO2 or carbon dioxide while breathing. That makes CO2 concentration a good indicator for the amount of fresh air supplied. In many applications, the CO2 sensor measurement is used to control the ventilation system. This HVAC sensor measures temperature, relative humidity and CO2 in air ducts. Based on the temperature and humidity, the dew point is calculated. This sensor will function best if it is installed in a straight section of the air duct. Avoid installation in turbulent air zones nearby filters, fans, cooling coils, etc. Position the sensor correctly with respect to the airflow direction. Please consult the mounting instructions for more detailed information.
Corrosion protected and ammonia resistant for the agricultural sector
The electronic components and the PCB of this duct transmitter are treated with a corrosion protective and ammonia resistant coating. The range of the CO2 measurement can be set in the range of 0 - 10.000 ppm. That range is wider than that of the standard CO2 sensors. This makes the sensor particularly suitable for the agricultural sector or applications with high humidity.
NDIR sensor technology
NDIR or Non-dispersive Infrared technology is used to measure the CO2 level. This technology offers a low life-cycle cost and a precise and stable long-term operation. This sensor has three analogue outputs. Each of them transmits one of the measured values. E.g. by default, output 1 will transmit 0 V at 0 °C and 10 V at 50 °C. Each output value varies proportionally in function of the measured temperature, humidity or CO2 concentration. The measured temperature is available via output 1, relative humidity via output 2 and CO2 concentration via output 3.
This sensor doesn't require configuration. Once installed, it is ready to use. The default settings will do for most applications. If necessary, the settings can be adjusted via Modbus RTU communication. For example, a different output type can be selected to make it compatible with other devices: 0-10 VDC / 0-20 mA / 0-100 % PWM. The Modbus register map provides a complete overview of all adjustable settings.
The supply voltage is 24 VDC. The ground terminals of the power supply (V-) and output (GND) are internally not connected. This means that a 4-wire cable is required to connect this sensor. Most 24 VDC power supplies offer protection against short circuit, overload and overvoltage. A 24 VDC supply voltage increases the safety and reliability of your installation.
Self-calibrating to compensate sensor drift
The ABC logic self-calibrating algorithm is by default enabled. This algorithm is designed to be used in applications where CO2 concentrations will drop to outside ambient conditions (400 ppm) at least one time (15 minutes) in a 7day period, which is typically seen during unoccupied periods. The sensor will reach its operational accuracy after 25 hours of continuous operation at a condition that it was exposed to ambient reference levels of air at 400 ppm ± 10 ppm CO2.
The enclosure is optimized for CO2 measurements in air ducts. It offers an IP54 protection against ingress of dust and moisture. The sensor element is integrated in the probe of the duct sensor. This probe has an opening to have a direct contact between the air flow and the sensor element. The sensor probe offers an IP20 protection.