Maintenance And Recalibration - Apogee SQ-640 Owner's Manual

MAINTENANCE AND RECALIBRATION

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.
Blocking of the optical path between the target and detector can cause low readings. Occasionally, accumulated
materials on the diffuser of the upward-looking radiometer and in the apertures of the downward-looking
radiometer can block the optical path in three common ways:
1. Moisture or debris on the diffuser (upward-looking) or in the apertures (downward-looking).
2. Dust during periods of low rainfall.
3. Salt deposit accumulation from evaporation of sea spray or sprinkler irrigation water.
Apogee Instruments upward-looking sensors have a domed diffuser and housing for improved self-cleaning from
rainfall, but active cleaning may be necessary. 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 cloth
or cotton swab. Salt deposits cannot be removed with solvents such as alcohol or acetone. Use only gentle
pressure when cleaning the diffuser with a cotton swab or soft cloth, to avoid scratching the outer surface. The
solvent should be allowed to do the cleaning, not mechanical force. Never use an abrasive material or cleaner on
the diffuser.
It is recommended that two-band radiometers be recalibrated every two years. See the Apogee webpage for
details regarding return of sensors for recalibration
recalibration-repairs/).
(http://www.apogeeinstruments.com/tech-support-