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TROUBLESHOOTING AND CUSTOMER SUPPORT
Cable Length
Fifteen feet is the maximum cable length that can be built into the sensor.
Modifying Cable Length
If you required a longer cable length an “active” USB extension cable is required. Please note, the connection between the
cables must be made water tight prior to submersion.
Unit Conversion Charts
Apogee SQ series quantum sensors are calibrated to measure PPFD in units of µmol m
-2
s
-1
. Units other than photon flux
density (e.g., energy flux density, illuminance) may be required for certain applications. It is possible to convert the PPFD
value from a quantum sensor to other units, but it requires spectral output of the radiation source of interest. Conversion
factors for common radiation sources can be found in the Knowledge Base on the Apogee website
(
http://www.apogeeinstruments.com/knowledge-base/
; scroll down to Quantum Sensors section). A spreadsheet to convert
PPFD to energy flux density or illuminance is also provided in the Knowledge Base on the Apogee website
(
http://www.apogeeinstruments.com/content/PPFD-to-Illuminance-Calculator.xls
).