240-3010-A Mechanical Pyranograph
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| 240-3010-A Mechanical Pyranograph |
The Model 240-3010-A Mechanical Pyranograph is a versatile, self-contained instrument. It provides a continuous recording of the intensity of global solar radiation (direct and diffuse), from which daily totals can be calculated.
A glass hemisphere on the top of the pyranograph transmits 90% of radiation in the 0.36 to 2 micron range. Radiation intensity is measured by bimetallic strips. Two white strips reflect radiation and therefore respond only to ambient temperature. Two black strips absorb radiation and so respond to incoming radiation as well as ambient temperature. One black and one white strip are connected so that the ambient conditions cancel each other. Thus, the remaining strip response represents incoming radiation. The opposite ends of the black strips are connected to each other and to the cartridge pen arm through a lever system. All components of the linkage are made of chrome-plated brass or stainless steel.
The self-contained clock is battery-operated. A selection switch allows recording for 1 or 7 days. Actual rotation periods for the daily and weekly choices are 26 hours and 176 hours, respectively, to prevent overwriting of the chart clip.
The 190-3012 5-foot mast is recommended for mounting the mechanical pyranograph at the standard measurement height. A bull's-eye level and adjustable feet assist in leveling. Gasket seals and a desiccant chamber prevent condensation of moisture inside the glass hemisphere. The instrument case is painted white to reflect radiation and prevent internal heating. A window on the side allows viewing of chart records.
Specifications
Sensor: Black and white bimetallic strips
Spectral response: 0.36 to 2.0 microns, 90% transmission
Recording range: approx 0 to 2.5 ly/min or 0 to 1500 W/m²
Lag coefficient: approx 5 minutes
Graduations: approx 0.05 ly/min or 30 W/m²
Chart size: 11.5" L x 3.5" H (292 mm x 89 mm)
Clock type: 1.5 Vdc battery-operated (2 AA cells)
Drum rotation: 1 day (26 hours) or 7 days (176 hours)
Pen type: cartridge
Leveling: 3 adjustable feet and bull's-eye level
Size: 13" L x 8.25" W x 8.75" H (330 x 210 x 222 mm)
Weight/shipping: 14 lbs/25 lbs (6.3 kg/11.2 kg)
Ordering Information
240-3010-A Mechanical Pyranograph, Discontinued
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