The Dwyer CDT Carbon Dioxide & Temperature Transmitter accurately monitors 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. To achieve a higher level of accuracy, the Series CDT includes digital barometric pressure adjustment and supports field calibration of the sensor. For applications that require visual indication, wall mount configurations of the Series CDT can be ordered with an integral LCD display. Push buttons are standard on all configurations for access to the menu structure, but wall mount configurations can be ordered without the buttons. To prevent tampering, the action of the buttons can be locked out using an internal dip switch selection.

Applications for the CDT include:

• Demand control ventilation in schools, office buildings, hospitals, and other indoor environments
• LEED certification

Features

• Single beam, dual-wavelength NDIR CO2 sensor
• Measuring ranges:
  • CO2: 0 to 2000 or 0 to 5000 ppm
  • Temperature: 32 to 122°F (0 to 50°C)
• Measurement accuracy:
  • CO2: ±40 ppm ±3% of reading
  • RH: ±2% (10 to 90% RH)
  • Temperature: ±1°C @ 25°C
• Compatible duct air velocity range: 0 to 4000 FPM (20.32 m/s)
• Enclosure ratings:
  • Duct mount: NEMA 4X (IP66) for housing only
  • Wall mount: IP20
• Digital barometric pressure adjustment for enhanced accuracy
• Automatic light source aging compensation
• Supports field calibration
• Optional integral LCD display
• Internal DIP switch for button tamper lockout