CDT-2N4B, Series CDT Carbon Dioxide/Temperature Transmitter, 0 to 2000 ppm CO2 range, North American Housing , 4 to 20 mA / 0 to (5 or 10) VDC (C02), 10 KΩ NTC thermistor type II (Temperature Output)The SERIES CDT Carbon Dioxide and Temperature Transmitter accurately monitor the CO2 concentration and temperature in indoor environments to help achieve energy savings. For increased sensor accuracy, a single beam dual wavelength nondispersive infrared (NDIR) sensor is used to automatically correct the measurement in both occupied* and unoccupied buildings against light source aging effects. The single beam dual wavelength sensor technology provides the highest level of accuracy compared to Automatic Baseline Correction methods which can unintentionally shift the calibration based on CO2 levels and barometric pressure conditions. In order to achieve a higher level of accuracy, the Series CDT includes digital barometric pressure adjustment and the ability to field-calibrate the sensor. To prevent tampering, the action of the buttons can be locked out using an internal dip switch selection.*For buildings occupied 24 hours per day, it is recommended that calibration be verified every 6 to 12 months depending on application.Single beam dual-wavelength sensor advantages:Automatically corrects for aging effects in occupied and unoccupied buildingsPerfect for hospitals and manufacturing plants that are occupied 24 hours per dayMeasures actual unfiltered light intensity directlyEliminates error from incorrect assumptions of gas concentration in theoretical logic assumption methodsFeatures:Single beam dual wavelength NDIR sensor eliminates draft due to light source agingIntegral passive temperature outputs reduce number of devices mounted in the spaceCompability with LED Display (Sold separatly)ApplicationsDemand control ventilation in schoolsOffice buildingsHospitalsOther indoor environmentsLEED® certification.