CO2 sensor

Application

The sensor is designed for indoor carbon dioxide concentration measurement and respective air capacity regulation through the control output signal to the fan. Air capacity control based on CO₂ concentration is an efficient energy saving solution.

Design and compatability

The sensor has two separate outputs: a normally opened dry relay contact and an analogue output 0…10 V (this output is adjustable for 2…10 V/0…20 mA/4…20 mA). The relay output is used to turn the fan on/off depending on indoor CO₂-concentration and the analogue output is used for smooth fan speed control for a fan with EC-motor or a fan with extra speed controller with 0-10 V input, refer to RS...TA or VFED. In case of smooth fan speed control the fan speed varies proportionally to carbon dioxide emissions. The relay and analogue outputs make the sensor compatible with any ventilation system. The integrated self-calibration system ensures reliable sensor operation during the sensor service life.

Modifications

The sensor is available in two modifications: CO2-1 and CO2-2. The CO2-1 model incorporates LED lights for CO₂ concentration and operation buttons indicating the level of three operation modes: 1 – on, 2 – off, 3 – operation by CO₂ concentration. The button is used to switch the ventilation system on or off when CO₂- based ventilation control is not required. The CO2-2 model has no LED-lights and on/off button. The model is applied for premises requiring permanent ventilation, i.e. at school classes and other public premises.

Mounting and power supply

The sensor is designed for wall surface mounting. 24 VAC low current power supply. If power supply 24 V is not available, connect the TRF plug that is offered as an accessory.