[. . . ] Box 26, FI-00421 Helsinki, FINLAND Tel: +358 9 89491, Fax: +358 9 8949 2485 E-mail: industrialsales@vaisala. com www. vaisala. com Vaisala FD12 Visibility Meter Features · Measurement range 10 to 50 000 m · Built-in compensation for different types of precipitation · Minimum of maintenance needed · Correct visibility data in any weather conditions The FD12 forward-scatter visibility meter evaluates the Meteorological Optical Range (MOR) by measuring the scatter of infrared light in air. [. . . ] Depending on the environment, the cleaning of the lenses is necessary only a few times per year; the device features automatic detection of contamination and, consequently, alarm for the need of cleaning. An extensive set of self diagnostic routines monitors sensor operation continuously. The failure can be easily located by enquiring the diagnostics about the sensor status. By utilizing digital techniques in hardware design and signal processing, the device exceeds the performance of other forwardscatter instruments. Fast pulse rate used enables precise recognition of weather conditions. The device has a built-in visibility calculation compensation for snow, fog, rain and sleet. The effects of stray light and severe weather are eliminated resulting in accuracy under all circumstances. [. . . ] +55 °C 35 kg with pole mast 20 kg with clamp mountings 210 cm (h) × 160 cm (w) Vaisala's DD50 Digital Display 300 baud Mast mounting clamps Wall mounting clamps Instrument consistency Variability between units Outputs & power supply Serial interfaces Analog output Power supply Power consumption Options Optional display unit Optional modem Optional fixings All specifications are subject to change without prior notice. [. . . ]