Contact Us Background Luminance Sensor LM21 Fully featured instrument designed for Runway Visual Range (RVR) Intelligent, stand-alone Background Luminance Sensor (An Ambient Light Sensor) for Runway Visual Range (RVR) and ICAO airport visibility systems. Easy to integrate with Vaisala LT31 and FS11 sensors. Features Intelligent, stand-alone sensor Verified accuracy and photopic response Extensive self-diagnostics Window contamination measurement and compensation Optical path blockage detection High power heaters to prevent snow accumulation Calibration traceable to measurement standards Field calibration device available Easy to calibrate + Show more Key Benefits Easy to calibrate The calibration of LM21 is traceable to international measurement standards for luminous intensity. Calibration starts automatically when Vaisala Field calibrator LMA21 is connected to LM21. Resembles Human Eye LM21 is a precision photometer with a verified photopic spectral response. It measures the total amount of light coming in from an angle of 6 degrees, and converts the measured data to cd/m2. Comprehensive Self-Diagnostics LM21 is an intelligent, standalone sensor. To ensure reliable and uninterrupted operation, it has extensive self-monitoring functions with high power heating features. Downloads Datasheet: LM21 Datasheet (861.66 KB) All downloads Services Transmissometer LT31 Operation and Maintenance Training Need support? Need to calibrate? Sign up for news Contact us
