LPPYRA11
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V1.1
•
Mount the albedometer 1 – 2 m above the ground. Grass should be kept at the
same height all the year long. In snowy regions, keep the instrument above the
blanket of snow so that the distance from the albedometer to the snow be constant.
•
The albedometer must be mounted in an easy-to-reach location in order to clean
the dome regularly and carry out maintenance. At the same time, make sure that
no buildings, constructions, trees or obstructions exceed the horizontal plane where
the upper pyranometer lies. If this is not possible, select a site where obstructions
in the path of the sun from sunrise to sunset do not exceed 5 degrees of elevation.
N.B.: The presence of obstructions on the horizon line affects significantly
the measurement of direct irradiance.
•
The pyranometer must be located far from any kind of obstruction, which might re-
flect sunlight (or sun shadow) onto the pyranometer itself.
•
In compliance with ISO TR9901 standard and WMO recommendations, when the
pyranometer is used without the white shade disk, it must be positioned so that its
connector is pointed to the North Pole, if the instrument is used in the Northern
Hemisphere, and to the South Pole, if used in the Southern Hemisphere. In any
case, it is better to follow this suggestion even when the shade disk is applied.
•
The mounting can be made using the rod provided with the instrument. In order to
allow an accurate horizontal positioning, the pyranometer is equipped with a level-
ling device. The mast height does not exceed the pyranometer plane to avoid
measurement errors caused by any reflection or shadow of the mast itself.
•
It is preferably to thermally insulate the pyranometer from its mounting bracket
ensuring, at the same time, a good electrical contact to ground.
Fig. 3.2: fixing and dimensions
Connector
Levelling device
LPSP1
LPSP3
Summary of Contents for Delta OHM LPPYRA11
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