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計測機器 Apogee MU-100のPDF オーナーズマニュアルをオンラインで閲覧またはダウンロードできます。Apogee MU-100 15 ページ。 Ultraviolet meter
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MAINTENANCE AND RECALIBRATION

Moisture or debris on the sensor is a common cause of low readings. The sensor has a domed-shaped housing for improved

self-cleaning from rainfall, but materials can accumulate on the photo-sensitive area (e.g., dust during periods of low rainfall,

salt deposits from evaporation of sea spray or sprinkler irrigation water) and partially block the optical path. Dust or organic

deposits are best removed using water, or window cleaner and a soft cloth or cotton swab. Salt deposits should be dissolved

with vinegar and removed with a soft cloth or cotton swab. Never use an abrasive material or cleaner on the sensor.

The Clear Sky Calculator (www.clearskycalculator.com) determines total shortwave radiation or photosynthetic photon flux

density (PPFD) incident on a horizontal surface at any time of day at any location in the world. It is most accurate when used

near solar noon in spring and summer months, where accuracy over multiple clear and unpolluted days is estimated to be ±

4 % in all climates and locations around the world.

Although the Clear Sky Calculator does not specifically report an estimated value for UV radiation, it can still be used to help

determine the need for UV sensor recalibration by approximating the ratio of UV to total shortwave or the ratio of UV to

PPFD. However, due to continuous changes in atmospheric conditions and their effect on UV radiation, the comparison of

the UV sensor to the Clear Sky Calculator should only be made in the summer months near solar noon, and under completely

clear skies.

To calculate a reference value of UV radiation in units of energy flux (W m

), input site conditions into the calculator to

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determine the estimated total shortwave radiation. Then multiply the estimated total shortwave value by an approximated

ratio value between 0.045 and 0.050 to convert the total shortwave radiation to total UV radiation.

To calculate a reference value of UV radiation in units of photon flux density (μmol m

), input site conditions into the

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calculator to determine the estimated PPFD. Then multiply the estimated PPFD by an approximated ratio value between

0.070 and 0.075 to convert the PPFD to total UV radiation.

If UV sensor measurements over multiple days near solar noon are consistently different than calculated values (by more

than 10 %), the sensor should be cleaned and re-leveled. If measurements are still different after a second test, email

to discuss test results and possible return of sensor(s).