The PMA2140 can be used to monitor the global
solar irradiance (direct + diffuse). It is factory calibrated to accurately read
the
global solar irradiance (from 300 to 2800nm) if exposed to the standard sun, even though
the detector is not sensitive beyond 1100nm. This is achieved by applying a correction
factor during calibration (see the calibration section). The radiant power within the
range of 400-1100nm constitutes about 75% of the total solar radiation for an overhead sun
under clear sky.
High sensitivity permits measurements of weak sources but caution is
advised when measuring artificial sources since the spectral distribution of the
source’s irradiance will affect the reading. A correction factor can be calculated to
take the spectral distribution into account.
The detector is equipped with a cosine diffuser that assures an angular response within
5% of the cosine function for incident angles less than 60 degrees. This
diffuser makes it suitable for
measurements of diffuse radiation and radiation from extended sources.
