The CWE are non-dispersive infrared (NDIR) analyzers designed for measuring environmental CO2 concentration in ventilation systems and indoor living spaces. Their measurement range of 0-2000ppm makes them compliant with ASHRAE and other standards for ventilation control. The CWE Series provides a user-selectable 4-20mA or 0-10VDC output for versatility. Microprocessor-based digital electronics and a unique self-calibration algorithm improves long-term stability and accuracy. APPLICATIONS Controlling ventilation in response to occupancy Facilitating compliance with ASHRAE 62.1-2004 standard for air quality Office buildings, conference rooms, schools, retail stores, etc. Microprocessor design increases accuracy and reduces installation time Non-dispersive infrared technology repeatable to ±20 ppm ±1% of measured value Innovative self-calibration algorithm...easy to maintain 5-year calibration interval (recommended) Low ambient sensitivity Alarm relay with setpoint for direct ventilation control Output 4-20mA/0-10V for flexible control system interface 3-year factory warranty from date of purchase