8. Maintenance and
troubleshooting
The SR20-D2 has no service items requiring scheduled replacement. There is no accessible
desiccant cartridge to maintain. Use pure alcohol or distilled water and a lint-free cloth to clean
the dome, removing smears and deposits. Local conditions and application dictate cleaning
interval. Sophisticated research applications require daily cleaning. For typical PV applications,
clean once per week, bi-monthly, or monthly. The SR20-D2 should be recalibrated following
industry standard best practices such as ASTM G167, ISO 9846, ASTM E824 or ASTM G207 by an
accredited lab. The recommended recalibration interval is two years. Contact Campbell Scientific
for more information.
Unexpected results typically occur because of improper wiring or programming, electromagnetic
radiation, or damaged cables. Ensure that the data logger program includes the correct
parameters for the measurement instructions. Check for the presence of strong sources of
electromagnetic radiation and use the 50 or 60 Hz integration option in the data logger program
if electromagnetic radiation can be a problem. Check the cable for damage and ensure that it is
properly connected to the data logger.
SR20-D2 ISO Spectrally Flat Class A (Secondary Standard) Pyranometer
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