The CEDT series of CO2 sensor uses a highly accurate and reliable Non‑Dispersive Infrared (NDIR) sensor in a duct mount enclosure to monitor return air CO2 levels for indoor applications. The compact dual wavelength CO2 sensor achieves excellent performance characteristics, including high accuracy and low power consumption to ensure stable long term operation. The CO2 sensor features user selectable 4‑20 mA or 0‑5 Vdc or 0‑10 Vdc for simple integration into any building automation system. A polycarbonate enclosure with a hinged and gasketed cover is provided for electrical connections.