1.2 Specifications
Capacity: unlimited
Orifice: 8” (20 cm) diameter
Calibration: O.Ol”, 1 mm, 0.5 mm, 0.25 mm
Accuracy: + 4% for rainfall rates of 1” to 6 ” per hour
Switch: magnetic sensitive, 3 W, 28 Vat
Construction:
Fabricated parts: anodized aluminum
Fasteners: stainless steel (except for aluminum rivets)
Mounting: 3 legs, l/4” diameter bolt holes on a
Dimensions: 8.4” D x 15 ” H
Shipping weight: 8 lbs
Optional Accessories: | Model |
Wind Screen, Alter Type | |
Event Recorder, Drum Chart | Model |
Calibrator Bottle | Model |
Digital Event Counter | Model |
Chapter 2: Installation |
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2.1 Site Requirements |
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Finding the best possible site for the gauge is important and careful consideration should be given to the quality of precipitation catch prior to the final installation. The most accurate rainfall measurements are made in sheltered areas that block wind and eddy currents in the vicinity of the gauge. The best exposures are often found in orchards or openings within a grove of trees, bushes, or shrubbery. Fences or other objects can act together to serve as an effective windbreak. As a general rule in such areas, the heights of the objects and the distance from the gauge should be uniform. The height of nearby objects above the gauge should not exceed about twice their distance from the gauge. Individual or small groups of isolated objects near a gauge may set up serious eddy currents. Since it is not always possible to select sites that provide adequate protection from adverse wind effects, an open site away from isolated objects may be the only location available. Wind Shields help minimize loss of precipitation catch by breaking up the air flow immediately over the gauge funnel. Wind effects on catch losses are much greater during snowfall than rainfall. Windshields are not generally installed at gauge site locations where snowfall constitutes less than 20% of the mean annual precipitation.
Good exposures are not always permanent. The growth of vegetation, trees, and shrubs can change an excellent exposure into an unsatisfactory one within a relatively short time. Sites should be inspected and groomed regularly.
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