These multifunctional HVAC sensors measure temperature, relative humidity and CO2in air ducts. All settings can be adjusted via Modbus RTU. Sentera CO2NDIR sensors transmit the measured values into an analogue output or a Modbus RTU register. The algorithm of the intelligent sensors controlsa single analogue output based on the measured temperature, relative humidityh and CO2values. They can directly control an EC fan, an AC fan speed controller or a damper actuator. The black mounting flange simplifies installation on circular ducts.