SQ-514-SS Full-Spectrum 4-20 mA output

The SQ-514 is an amplified full-spectrum quantum sensor with a 4 to 20 mA output. The sensor was designed for use in environments with significant background electrical noise that can be found in many industrial applications. The sensor features a rugged, self-cleaning sensor housing design, and high-quality cable terminating in pre-tinned pigtail leads for easy connection to dataloggers and controllers. Typical applications include PPFD (Photosynthetic Photon Flux Density) 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 (Photosynthetically Active Radiation)/PPFD in aquatic environments, including salt water aquariums where corals are grown. Sensor includes IP68 marine-grade stainless-steel cable connector 30 cm from head to simplify sensor removal and replacement for maintenance and recalibration

How is the SQ-514 different from previous Apogee quantum sensors?
The SQ-514 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 response increases the accuracy of LED measurements.

Where is the SQ-514 used?
The SQ-514 is used to measure incoming PPFD measurements in outdoor environments, greenhouses, growth chambers, and aquariums.

Specifications

• Power Supply: 12 to 24 V DC
• Current Draw: maximum of 20 mA
• Output (sensitivity): 0.004 mA per µmol mˉ² sˉ¹
• Calibration Factor: 250 µmol mˉ² sˉ¹ per mA
•  Calibration Uncertainty: ± 5 %
• Output Range: 4 to 20 mA
• 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: 391 to 695 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 ± 2 % at 45˚ zenith angle, ± 5 % at 75˚zenith angle
• Azimuth Error: Less than 0.5 %
• Tilt Error: Less than 0.5 %
• Temperature Response: -0.1 % per C
• 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: 30.5 mm diameter, 37 mm height
• Mass (with 5 m of cable): 140 g
• Cable: 5 m of two conductor, shielded, twisted-pair wire; TPR jacket; pigtail lead wires; stainless steel (316), M8 connector
• Warranty: 4 years against defects in materials and workmanship
• Manufactured: Assembled in the USA