GHM Delta OHM LPPIRG01, Operating Manual, Page: 16 / 26

LPPIRG01
- 16 -
V2.1
7 MAINTENANCE
In order to grant measurements high accuracy, it is important to keep the silicon win-
dow clean. Consequently, the more the dome will be kept clean, the more measure-
ments will be accurate.
You can wash it using water and standard papers for lens. If necessary, use pure ETHYL
alcohol. After using alcohol, clean again the silicon window with water only.
Because of the high temperature changes between day and night, some condensation
might appear inside the pyrgeometer (especially on the silicon window). In this case
the performed reading is wrong. To minimize the condensation, the pyrgeometer is
provided with a cartridge containing dessicant material (silica-gel). The efficiency of the
silica-gel crystals decreases over time while absorbing humidity. Silica-gel crystals are
efficient when their color is yellow, while they turn white/translucent as soon as
they lose their efficiency. Read instructions at chapter 3 about how to replace the silica-
gel crystals. Silica-gel typical lifetime goes from 2 to 6 months depending on the envi-
ronment where the pyrgeometer works.
Hail of particular intensity/size may damage the silicon window; therefore, it is recom-
mended to check the status of the window after an intense storm with hail.
To exploit all the pyrgeometer features, it is highly recommended that the calibration
be checked annually.