RoHS 3 compliant using exemption 6c. Further note that Apogee Instruments does not specifically run any analysis on our raw materials or end products for the presence of these substances, but rely on the information provided to us by our material suppliers.
(transmitted) PPFD measurement in the same environments. Apogee Instruments SQ series quantum sensors consist of a cast acrylic diffuser (filter), photodiode, and signal processing circuitry mounted in an anodized aluminum housing, and a cable to connect the sensor to a measurement device.
Sensor model number and serial number are located on the bottom of the sensor. If you need the manufacturing date of your sensor, please contact Apogee Instruments with the serial number of your sensor. Serial Number 0-10573 (SQ-212), 0-10273 (SQ-...
(SQ-222), 10434 (SQ-215), 10534 (SQ-225) and above Dimensions Serial # 0-10573 (SQ-212), 0- 24 mm diameter, 33 mm height 10273 (SQ-222), 0-10433 (SQ- 215), 0-10533 (SQ-225) Mass (with 5 m cable) Serial # 10574 (SQ-212), 10274 140 g (SQ-222), 10434 (SQ-215),...
Page 7
Calibration Traceability Apogee SQ series quantum sensors are calibrated through side-by-side comparison to the mean of transfer standard quantum sensors under a reference lamp. The reference quantum sensors are recalibrated with a 200 W quartz halogen lamp traceable to the National Institute of Standards and Technology (NIST).
Page 8
Directional (cosine) response is defined as the measurement error at a specific angle of radiation incidence. Error for Apogee SQ-100 series quantum sensors is approximately ± 2 % and ± 5 % at solar zenith angles of 45° and 75°, respectively.
Mount the sensor to a solid surface with the nylon mounting screw provided. To accurately measure PPFD incident on a horizontal surface, the sensor must be level. An Apogee Instruments model AL-100 Leveling Plate is recommended to level the sensor when used on a flat surface or being mounted to surfaces such as wood. To facilitate mounting on a mast or pipe, the Apogee Instruments model AL-120 Solar Mounting Bracket with Leveling Plate is recommended.
Instructions Pins and Wiring Colors: All Apogee connectors have six pins, but not all pins are used for every sensor. There may also be unused wire colors inside the cable. To simplify connection to a measurement device, the unused pigtail lead wire colors are removed.
DO NOT connect the sensor to a power source greater than 24 VDC. VERY IMPORTANT : Apogee changed the wiring colors of all our bare-lead sensors in March 2018 in conjunction with the release of inline cable connectors on some sensors. To ensure proper connection to your data device, please note your serial number or if your sensor has a stainless-steel connector 30 cm from the sensor head then use the appropriate wiring configuration listed below.
Page 12
Sensor Calibration Serial Number Range 0-8381. Apogee amplified quantum sensor models have a standard PPFD calibration factor of exactly: SQ-212, SQ-222: 1.0 µmol m per mV SQ-215, SQ-225: 0.5 µmol m per mV Multiply this calibration factor by the measured mV signal to convert sensor output to PPFD in units of µmol m Calibration Factor (0.5 µmol m...
Page 13
Spectral errors for PPFD measurements made under common radiation sources for growing plants were calculated for Apogee SQ-100/300 and SQ-500 series quantum sensors using the method of Federer and Tanner (1966). This method requires PPFD weighting factors (defined plant photosynthetic response), measured sensor spectral response (shown in Spectral Response section on page 7), and radiation source spectral outputs (measured with a spectroradiometer).
Page 14
Yield Photon Flux Density (YPFD) Measurements Photosynthesis in plants does not respond equally to all photons. Relative quantum yield (plant photosynthetic efficiency) is dependent on wavelength (green line in figure below) (McCree, 1972a; Inada, 1976). This is due to the combination of spectral absorptivity of plant leaves (absorptivity is higher for blue and red photons than green photons) and absorption by non-photosynthetic pigments.
Page 15
(YPFD) for multiple different radiation sources. YPFD is approximately 90 % of PPFD. Measurements were made with a spectroradiometer (Apogee Instruments model PS-200) and weighting factors shown in the previous figure were used to calculate PPFD and YPFD.
Page 16
Apogee SQ-100 series and SQ-300 series quantum sensors have an immersion effect correction factor of 1.08. This correction factor should be multiplied by PPFD measurements made underwater to yield accurate PPFD.
Never use abrasive material or cleaner on the diffuser. Although Apogee sensors are very stable, nominal calibration drift is normal for all research-grade sensors. To ensure maximum accuracy, recalibration every two years is recommended. Longer time periods between recalibration may be warranted depending on tolerances.
Page 18
Homepage of the Clear Sky Calculator. Two calculators are available: one for quantum sensors (PPFD) and one for pyranometers (total shortwave radiation). Clear Sky Calculator for quantum sensors. Site data are input in blue cells in middle of page and an estimate of PPFD is returned on right-hand side of page.
1 mega-ohm there is negligible effect on the calibration, even after adding up to 100 m of cable. All Apogee sensors use shielded, twisted pair cable to minimize electromagnetic interference. For best measurements, the shield wire must be connected to an earth ground. This is particularly important when using the sensor with long lead lengths in electromagnetically noisy environments.
Page 20
Unit Conversion Charts Apogee SQ series quantum sensors are calibrated to measure PPFD in units of µmol m . Units other than photon flux density (e.g., energy flux density, illuminance) may be required for certain applications. It is possible to convert the PPFD value from a quantum sensor to other units, but it requires spectral output of the radiation source of interest.
RETURN AND WARRANTY POLICY RETURN POLICY Apogee Instruments will accept returns within 30 days of purchase as long as the product is in new condition (to be determined by Apogee). Returns are subject to a 10 % restocking fee. WARRANTY POLICY...
Page 22
84321, USA 5. Upon receipt, Apogee Instruments will determine the cause of failure. If the product is found to be defective in terms of operation to the published specifications due to a failure of product materials or craftsmanship, Apogee Instruments will repair or replace the items free of charge.
Need help?
Do you have a question about the SQ-222 and is the answer not in the manual?
Questions and answers