SQ-500-SS Full-Spectrum Quantum Sensor

The SQ-500 is a self-powered, analog full-spectrum quantum sensor with a 0 to 40 mV output.

  • Product Name:Full-spectrum Quantum Sensor
  • Model:SQ-500-SS
  • Maunufactor:Apogee
  • Country:USA

The SQ-500 is a self-powered, analog full-spectrum quantum sensor with a 0 to 40 mV output. The sensor incorporates a blue-enhanced silicon photodiode and custom optical filters with a rugged, self-cleaning sensor housing design, anodized aluminum body with acrylic diffuser. Typical applications include PPFD measurement over plant canopies in outdoor environments, greenhouses, and growth chambers, and reflected or under-canopy (transmitted) PPFD measurements in the same environments. Quantum sensors are also used to measure PAR/PPFD in aquatic environments, including salt water aquariums where corals are grown. Sensor includes IP67 marine-grade stainless-steel cable connector 30 cm from head to simplify sensor removal and replacement for maintenance and recalibration.

How is the SQ-500 differentfrom previous Apogee quantum sensors?

The SQ-500 is a full spectrum quantum sensor with a spectral range of 389 to 692 nm ± 5 nm, which can be seen in the graph below. This improved spectral respose increases the acuracy of LED measurements.


Where is the SQ-500 used?

The SQ-500 is used to measure incoming PPFD measurements in outdoor environments, greenhouses, growth chambers, and aquariums.

Power Supply    Self-powered

Output (Sensitivity)    0.01 mV per µmol mˉ² sˉ¹

Calibration Factor (Reciprocal of Sensitivty)    100 µmol mˉ² sˉ¹ per mV

Calibration Uncertainty    ± 5 %

Calibrated Output Range    0 to 40 mV

Measurement Range    0 to 4000 µmol mˉ² sˉ¹

Measurement Repeatability    Less than 0.5 %

Long-term Drift     Less than 2 % per year

Non-linearity    Less than 1 % (up to 4000 µmol mˉ² sˉ¹)

Response Time     Less than 1 ms

Field of View    180 ˚

Spectral Range    389 to 692 nm ± 5 nm (wavelegths where response is greater than 50 % of maximum)

Spectral Selectivity    Less than 10 % from 412 to 682 nm ± 5 nm

Directional (Cosine) Response    ± 5 % at 75 ˚ zenith angle

Azimuth Error    Less than 0.5 %

Tilt Error    Less than 0.5 %

Temperature Response    -0.11 ± 0.04 % Cˉ¹

Uncertainty in Daily Total    Less than 5 %

Detector    Blue-enhanced silicon photodiode

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    24 mm diameter, 37 mm height

Mass     100 g (with 5 m of lead wire)

Cable    5 m of shielded, twisted-pair wire with TPR jacket (high water resistance, high UV stability, flexibility in cold conditions)

Warranty    4 years against defects in materials and workmanship