Specification Sheet

www.apogeeinstruments.com | 435.792.4700 | Logan , UT
Product Specicaons
Input Voltage Requirement 5.5 to 24 V DC
Current Draw 0.6 mA (quiescent), 1.3 mA (acve) 12.6 mA (quiescent), 13.5 mA (acve)
Calibraon Uncertainty ± 5 %
Measurement Repeatability Less than 0.5 %
Long-term Dri (non-stability) Less than 2 % per year
Non-linearity Less than 1 % (up to 4000 μmol m⁻² s⁻¹)
Response Time
0.6 s, me for detector signal to reach 95 % following a step
change; fastest data transmission rate for SDI-12 circuitry is 1 s
320 ms
Field of View 180°
Spectral Range 410 to 655 nm (wavelengths where response is greater than 50 % of maximum)
Spectral Selecvity Less than 10 % from 469 to 653 nm
Direconal (Cosine) Response ± 5 % at 75° zenith angle
Temperature Response 0.06 ± 0.06 % per C
Operang Environment -40 to 70 C; 0 to 100 % relave humidity; can be submerged in water up to depths of 30 m
Dimensions 44 mm height, 23.5 mm diameter
Mass 117 g (with 5 m of lead wire)
Cable
5 m of shielded, twisted-pair wire with TPR jacket (high water resistance, high UV stability, exibility in
cold condions); pigtail lead wires
Warranty 4 years against defects in materials and workmanship
SQ-422-SSSQ-421-SS
Mean cosine response of (7) Apogee SQ-500 quantum sensors. Cosine response
measurements were made on the rooop of the Apogee building in Logan, UT. Cosine
response was calculated as the relave dierence of SQ-500 quantum sensors from
the mean of replicate reference quantum sensors (LI-COR models LI-190 and LI-190R,
Kipp & Zonen model PQS 1). The red data are AM measurements; the blue data are PM
measurements.
Cosine Response
Mean temperature response of (8) SQ series quantum sensors (errors bars represent
two standard deviaons above and below mean). Temperature response measurements
were made at 10 C intervals across a temperature range of approximately -10 to 40 C
in a temperature controlled chamber under a xed, broad spectrum electric lamp. At
each temperature set point, a spectroradiometer was used to measure light intensity
from the lamp and all quantum sensors were compared to the spectroradiometer. The
spectroradiometer was mounted external to the temperature control chamber and
remained at room temperature during the experiment.
Temperature Response
Mean spectral response of (6) SQ series
quantum sensors (error bars represent
two standard deviaons above and below
mean) compared to PPFD weighng
funcon. Spectral response measurements
were made at 10 nm increments across
a wavelength of 300 to 800 nm in a
monochromator with an aached electric
light source. Measured spectral data from
each quantum sensor were normalized
by the measured spectral response
of the monochromator/electric light
combinaon, which was measured with a
spectroradiometer.
Spectral Response