Apogee's newest, cutting-edge ePAR sensor was created in 2021 as an upgrade to our ePFD sensor and designed to measure the newly defined 400-750 nm ePAR radiation range that research has shown to be photosynthetically active, beyond the traditional 400-700 nm range. The SQ-617 ePAR is a digital sensor with SDI-12 communication protocol. The sensor features a rugged, aluminum housing that is fully-submersible and built to withstand harsh conditions, and high-quality cable terminating in pre-tinned pigtail leads for easy connection to dataloggers and controllers. The sensor cable includes an IP68 marine-grade stainless-steel cable connector to simplify sensor removal and replacement from permanent installations for maintenance and calibration. Typical applications of ePAR sensors include measuring total ePAR intensity over plant canopies in all growing environments, monitoring and adjusting grow lights, and researching plant morphogenic activity and photobiology. Many next generation LED fixtures, the sun, and other light sources emit these newly confirmed Far-red photosynthetic wavelengths, but they have not been measurable by traditional 400-700 nm PAR meters until now.
The analog version of this sensor (SQ-610) comes with the inline cable connector placed 30 cm from the sensor head for either standard use as a long-cable pigtail sensor, or for use with our microCache Bluetooth Micro Logger by unscrewing the connector, discarding the long section of cable and then screwing the sensor to the mating connector on the microCache.
Input Voltage5.5 to 24 V DCCurrent Draw1.4 mA (quiescent), 1.8 mA (active)Calibration Uncertainty± 5 %Measurement Range0 to 4000 µmol mˉ² sˉ¹Measurement RepeatabilityLess than 0.5 %Long-term DriftLess than 2 % per yearNon-linearityLess than 1 % (up to 4000 µmol m⁻² s⁻¹)Response TimeLess than 1 msField of View180˚Spectral Range400 to 750 ± 5 nm (wavelengths where response is greater than 50 %)Directional (Cosine) Response± 2 % at 45˚; ± 5 % at 75˚ zenith angleAzimuth ErrorLess than 0.5 %Tilt ErrorLess than 0.5 %Temperature Response-0.11 ± 0.04 % per CUncertainty in Daily TotalLess than 5 %HousingAnodized aluminum body with acrylic diffuserIP RatingIP68Operating Environment-40 to 70 C; 0 to 100 % relative humidity; can be submerged in water up to depths of 30 mDimensions30.5 mm diameter, 37 mm heightMass (with 5 m of cable)140 gCable5 m of two conductor, shielded, twisted-pair wire; additional cable available in multiples of 5 m; TPR jacket; pigtail lead wires; stainless steel (316), M8 connectorWarranty4 years against defects in materials and workmanshipManufacturedMade in the USA