Ceilometers CL31 and CL51 Automated backscatter profiling captures detailed measurements on cloud base height and vertical visibility for multiple cloud layers — even in harsh conditions. Accuracy in all conditions Accuracy in all conditions Vaisala ceilometers accurately measure ceiling or base height of cloud layers, and they leverage pulsed diode lidar technology and single lens optics. They are engineered to deliver highly accurate data on multiple cloud layers even when conditions limit physical visibility.The CL31 model detects three cloud layers simultaneously to a range of 7.6 km (25,000 ft) and generates a full scope of measurements including precise assessment of inversion layers and nocturnal stable layers below 200 meters (650 ft).The CL51 model is designed for high-range, cirrus cloud height profiling that also includes detailed data on low and middle layer clouds as well as vertical visibility. It has a detection range up to 15 km (49,200 ft). FULLY AUTOMATED, 24/7 OPERATION FULLY AUTOMATED, 24/7 OPERATION Built to deliver in all conditions — even in extreme weather — the ceilometers provide data protected by backup battery, comprehensive self-diagnostics with contamination monitoring, and status reporting. Sensor reliability is boosted by optical filters for solar defense and tiltable automatic window blower with heater. EXCEPTIONAL DETECTION EXCEPTIONAL DETECTION Even when physical visibility is limited, the CL31 detects three cloud layers simultaneously and generates a full range of measurements including precise assessment of inversion layers and nocturnal stable layers below 200 m (650 ft). The CL51 also detects three cloud layers simultaneously — including the detection of Cirrus clouds — even under the most demanding conditions. RELIABILITY FROM GROUND UP RELIABILITY FROM GROUND UP Enhanced single lens technology allows Vaisala ceilometers to deliver highly accurate data on multiple cloud layers with a strong, stable signal over their full measurement range. The CL31 detects from ground-level fog to a vertical ceiling of 7.6 km (25,000 ft), while the CL51 has a full cloud reporting range up to 13 km (43,000 ft) and backscatter profiling over full range up to 15 km (49,200 ft). AFFORDABLE OWNERSHIP AFFORDABLE OWNERSHIP Nominal maintenance requirements and low operational costs are driven by extensive self-diagnostics, automated field adjustments and the practical modularity of engineering built into the Vaisala ceilometers. Industry Applications Aviation Ensure safe and efficient airport operations in any weather with our comprehensive selection of weather and runway management solutions. LEARN MORE Ground Transportation Tackle the toughest road maintenance challenges with our year-round weather and road condition monitoring technology, including AI-powered data collection and analysis. LEARN MORE Maritime Ensure safety and efficiency onshore and offshore with complete maritime weather management solutions; air quality, sea state, and helideck monitoring; and ship instrumentation. LEARN MORE Meteorology Protect people and communities from the impacts of day-to-day and extreme weather with the industry's most accurate and reliable weather observation solutions. LEARN MORE Urban Environment Boost situational awareness and improve quality of life with cutting-edge air quality monitoring solutions, road asset management, and accurate weather modeling for drones. LEARN MORE Get Started with Ceilometer CL Series Today Contact Vaisala to learn how you can tackle the specific challenges of cloud height and mixing layer height measurement — especially for low clouds and low inversion layers, precipitation, and fog. Get comprehensive, actionable understanding of meteorological conditions, exactly when you need it. CONTACT US Resources PRODUCT SPOTLIGHT CEILOMETER CL31 Capture accurate, reliable cloud base height, and vertical visibility data on multiple cloud layers to 25,000 feet (7.6 km). DOWNLOAD PDF DATASHEET CEILOMETER CL31 See technical data for this compact and lightweight instrument for cloud base height and vertical visibility measurements. DOWNLOAD PDF MORE DOWNLOADS CL31 Product Support & Scientific Downloads Click here to explore additional product resources for CL31. READ MORE ARTICLE Automatic Monitoring of Boundary Layer Structures with Ceilometers Read how the retrieving boundary layer structure data is enabling new ceilometer uses for air quality monitoring and forecasting. DOWNLOAD PDF PRODUCT SPOTLIGHT CEILOMETER CL51 Explore high-range cirrus cloud height detection with a range up to 15 km (49,200 ft). DOWNLOAD PDF DATASHEET CEILOMETER CL51 Get more detail about how CL51 measures high?range cirrus cloud heights in harsh conditions. DOWNLOAD PDF MORE DOWNLOADS CL51 Product Support & Scientific Downloads Click here to explore additional product resources for CL51. READ MORE ARTICLE Urban Air Quality – A Significant Threat to Human Health? Read about ceilometer use in cities for air quality estimates and forecast. DOWNLOAD PDF Success Stories Royal Meteorological Institute of Belgium Relies on Vaisala for Critical Air Quality Data SUCCESS STORY: The Royal Meteorological Institute of Belgium gains 24-hour visualization of current and near future air quality. READ MORE Innovative Air Quality Application to Increase the Knowledge, Control and Management of Air Quality SUCCESS STORY: Italian R&D agency creates an innovative air quality data processing system to study the interaction between pollutants and meteorological factors. DOWNLOAD PDF
