SPECIFICATIONS
Calibration Traceability
Apogee Instruments SQ-600 series quantum light pollution sensors are calibrated through side-by-side comparison
to the mean of four transfer standard quantum light pollution sensors under a reference lamp. The transfer
standard quantum light pollution sensors are recalibrated with a quartz halogen lamp traceable to the National
Institute of Standards and Technology (NIST).
SQ-646
Resolution
0.1 µmol m
-2
s
-1
Calibration Factor
Custom for each sensor and stored in the firmware
Calibration Uncertainty
± 5 % (see calibration Traceability below)
Measurement Range
0 to 200 µmol m
-2
s
-1
Measurement Repeatability
Less than 0.5 %
Long-term Drift
(Non-stability)
Less than 2 % per year
Non-linearity
Less than 1 % (up to 200 µmol m
-2
s
-1
)
Response Time
Software updates every second
Field of View
180°
Spectral Range
340 to 1040 nm ± 5 nm (wavelengths where response is greater than 50 %; see Spectral
Response below)
Directional (Cosine) Response
± 2 % at 45° zenith angle, ± 5 % at 75° zenith angle (see Cosine Response below)
Temperature Response
-0.11± 0.04 % per C
Azimuth Error
Less than 0.5 %
Tilt Error
Less than 0.5 %
Housing
Anodized aluminum body with acrylic diffuser
IP Rating
IP68
Operating Environment
-40 to 70 C, 0 to 100 % relative humidity, can be submerged in water up to depths of 30 m
Dimensions
30.5 mm diameter, 37 mm height
Mass (with 5 m of cable)
140 g
USB Cable
4.5 m (15 ft)
Current Draw (when Logging)
61 mA
