User Manual

SPECIFICATIONS
Calibration Traceability
Apogee SQ series quantum sensors are calibrated through side-by-side comparison to the mean of transfer
standard quantum sensors under a reference lamp. The reference quantum sensors are recalibrated with a 200 W
quartz halogen lamp traceable to the National Institute of Standards and Technology (NIST).
SQ-214/SQ-224-SS
Power Supply
7 to 24 V DC with a maximum current draw 22 mA (2 mA quiescent current draw)
Sensitivity
0.004 mA per µmol m
-2
s
-1
Calibration Factor
250 µmol m
-2
s
-1
per mA (reciprocal of sensitivity)
Calibration Uncertainty
± 5 % (see calibration Traceability below)
Calibrated Output Range
4 to 20 mA
Measurement
Repeatability
Less than 0.5 %
Long-term Drift
(Non-stability)
Less than 2 % per year
Non-linearity
Less than 1 % (up to 4000 µmol m
-2
s
-1
; maximum PPFD measurement is 4000 µmol m
-2
s
-1
Response Time
Less than 1 ms
Field of View
180°
Spectral Range
410 to 655 nm (wavelengths where response is greater than 50 % of maximum;
see Spectral Response below)
Spectral Selectivity
Less than 10 % from 469 to 655 nm
Directional (Cosine)
Response
± 5 % at 75° zenith angle (see Cosine Response below)
Temperature Response
0.06 ± 0.06 % per C (see Temperature Response below)
Operating Environment
-40 to 70 C; 0 to 100 % relative humidity; can be submerged in water up to depths of 30 m
Dimensions
24 mm diameter, 33 mm height
Mass
100 g (with 5 m of lead wire)
Cable
5 m of four conductor, shielded, twisted-pair wire; TPR jacket; pigtail lead wires; stainless steel
(316), M8 connector located 25 cm from sensor head