HTabsOverviewThe CAPS-DPOL is a multipurpose, research-grade cloud spectrometer that includes three Droplet instruments (CIP, LWC, and CAS); temperature and relative humidity sensors; and polarization measurement to discriminate between water and ice. Key Features Broad array of data Combine multiple probes with ranges optimized to measure cloud particles prior to and during transition to precipitation. Extreme versatility CAS measures aerosol particle and cloud hydrometeor size distributions from 2 µm to 50 µm; CIP measures precipitation size distributions from 25 µm to 1550 µm, and LWC measures liquid water content from 0.01 g/m3 to 3 g/m3, along with aircraft velocity, and atmospheric temperature and pressure. Advanced precision Gather data on particle optical properties (refractive index), as well as particle shape assessments (discrimination between water and ice for probes with depolarization feature). CAPS.pdf SpecificationSpecification: Parameter CIP Specification CAS Specification LWC Specification Technique Optical Array Probe with 64 elements: 62 sizing elements, end diodes reject Forward- and Back-Scatter Light Sensors Temperature-Controlled Hotwire Sensor Measured Particle Size Range 12.5 µm – 1.55 mm (standard) 0.51 µm to 50 µm N/A; measured LWC range is 0 - 3 g/m3 Sample Area 10 cm x 1.55 mm 11.1 mm x 120 µm N/A Upper Concentration Range Depends on particle size, but up to 500 particles/ cm3 for a CIP with standard tips and arm width Greater than 1,000 particles/cm3 after corrections for coincidence that are about 25% at 800 and 30% at 1,000 particles/cm3 3 g/m3 Air Speed Range 10 - 300 m/s 10 - 200 m/s 10 - 200 m/s Number of Size Bins 62 Selectable; 10, 20, 30, or 40 N/A Sampling Frequency 1D histogram data: 0.05 to 40 Hz 2D image data: variable interval, when buffer fills Selectable, 0.05 to 40 Hz N/A Laser 658 nm, 30 mW 658 nm, ~50 mW N/A Light-scattering Parameters N/A Non-absorbing refractive index: 1.3 – 1.7Light collection angles: 4° - 12°, 168° - 176° N/A Auxiliary Parameters Ambient Temperature, Relative Humidity, Static Pressure, Dynamic Pressure (CIP) N/A N/A Data System Interface: 2D CIP data: RS-422, High Speed, 4 Mb/sec Baud Rate System data: RS-422, 56.6 kb/sec Baud Rate Weight 45 lbs./20.4 kg Power Requirements 28VDC: 10A for probe system, and 45A for anti-ice heaters, optional AC voltages for anti-ice heaters Environmental Operating Conditions Temperature: 0 – 40°C (32 – 104 °F) RH: 0 – 100%, non-condensing Further InfoDocuments: CAPS.pdf
