<span style="font-size: 12px">The following is from Apogee's instructions (I think the BEST source for this)-
All Apogee quantum sensor models have a standard calibration of exactly:
</span><span style="font-family: Arial,Arial"><span style="font-size: 11px"><span style="font-family: Arial,Arial"><span style="font-size: 11px"><p style="text-align:center">5.00 </span></span></span></span><span style="font-size: 11px"><span style="font-family: Times New Roman"><span style="font-size: 11px">μ</span></span></span><span style="font-family: Arial,Arial"><span style="font-size: 11px"><span style="font-family: Arial,Arial"><span style="font-size: 11px">mol m</span></span></span></span><span style="font-family: Arial,Arial"><span style="font-size: 11px"><span style="font-family: Arial,Arial"><span style="font-size: 11px">-2 </span></span></span></span><span style="font-family: Arial,Arial"><span style="font-size: 11px"><span style="font-family: Arial,Arial"><span style="font-size: 11px">s</span></span></span></span><span style="font-family: Arial,Arial"><span style="font-size: 11px"><span style="font-family: Arial,Arial"><span style="font-size: 11px">-1 </span></span></span></span><span style="font-family: Arial,Arial"><span style="font-size: 11px"><span style="font-family: Arial,Arial"><span style="font-size: 11px">per mV
</span></span></span></span><span style="font-size: 12px">Use this conversion factor to convert the mV signal from the sensor to photosynthetic photon flux. Multiply the mV output by the conversion factor to get </span><span style="font-family: Skia,Skia"><span style="font-size: 12px"><span style="font-family: Skia,Skia"><span style="font-size: 12px">μ</span></span></span></span><span style="font-size: 12px">mol m</span><span style="font-size: 11px">-2 </span><span style="font-size: 12px">s</span><span style="font-size: 11px">-1</span><span style="font-size: 12px">.
</span><span style="font-family: Arial,Arial"><span style="font-size: 11px"><span style="font-family: Arial,Arial"><span style="font-size: 11px"><p style="text-align:center">Full Sunlight(2000 </span></span></span></span><span style="font-size: 11px"><span style="font-family: Times New Roman"><span style="font-size: 11px">μ</span></span></span><span style="font-family: Arial,Arial"><span style="font-size: 11px"><span style="font-family: Arial,Arial"><span style="font-size: 11px">mol m</span></span></span></span><span style="font-family: Arial,Arial"><span style="font-size: 11px"><span style="font-family: Arial,Arial"><span style="font-size: 11px">-2 </span></span></span></span><span style="font-family: Arial,Arial"><span style="font-size: 11px"><span style="font-family: Arial,Arial"><span style="font-size: 11px">s</span></span></span></span><span style="font-family: Arial,Arial"><span style="font-size: 11px"><span style="font-family: Arial,Arial"><span style="font-size: 11px">-1</span></span></span></span><span style="font-family: Arial,Arial"><span style="font-size: 11px"><span style="font-family: Arial,Arial"><span style="font-size: 11px">)
</span></span></span></span><span style="font-size: 12px">Sensor Output
(400 mV)
sensor output * conversion factor = PPF
400 mV * 5.00 </span><span style="font-family: Skia,Skia"><span style="font-size: 12px"><span style="font-family: Skia,Skia"><span style="font-size: 12px">μ</span></span></span></span><span style="font-size: 12px">mol m</span><span style="font-size: 11px">-2 </span><span style="font-size: 12px">s</span><span style="font-size: 11px">-1 </span><span style="font-size: 12px">per mV = 2,000 </span><span style="font-family: Skia,Skia"><span style="font-size: 12px"><span style="font-family: Skia,Skia"><span style="font-size: 12px">μ</span></span></span></span><span style="font-size: 12px">mol m</span><span style="font-size: 11px">-2 </span><span style="font-size: 12px">s</span><span style="font-size: 11px">-1
</span><span style="font-family: Arial,Arial"><span style="font-size: 13px"><span style="font-family: Arial,Arial"><span style="font-size: 13px">4
Also, it is recommended to purchase the sensor calibrated for electric sources (not sunlight) as the response curve calibration is more accurate for our electric lamps.
<font size="2"><!-- gcu-updated -->Calibrated for electric light; <u>SQ-120</u> (correct model to use, according to Apogee)
So in short, hook the red & black leads to a multimeter and <u>the reading will be 5 micromoles per millivolt.</u>
Red lead should go to red and the black lead to black. For 'Autoranging Multimeters' you don't need to worry about getting the leads correct, as this will just cause the polarity (+/-) to be reversed if it's not. The irradiance (quantity) will still be correct.
(we are converting light to a voltage here, and measuring that)
Complete manual link below
http://www.apogeeinstruments.com/manuals/SQ100_300_400.pdf">http://www.apogeeinstruments.com/manuals/SQ100_300_400.pdf</a>
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